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<!-- Creation Date :2026-03-04T14:54:13.9328+00:00 -->
<!-- Copyright (c) 2026 Donnelley Financial Solutions, Inc. All Rights Reserved. -->
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="country_IS_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Iceland</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialAssumptionOfDiscountRates_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Discount rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialAssumptionOfDiscountRates_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Actuarial assumption of discount rates</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialAssumptionOfDiscountRates_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Assumption of discount rates</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutConsiderationIsSubjectToForfeitureTargetThree_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnout consideration is subject to forfeiture target three</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutConsiderationIsSubjectToForfeitureTargetThree_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnout consideration is subject to forfeiture target three</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutConsiderationIsSubjectToForfeitureTargetThree_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Earnout consideration is subject to forfeiture target three.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCurrentReportingStatus_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Current Reporting Status</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCurrentReportingStatus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Current Reporting Status</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncreaseDecreaseThroughSharebasedPaymentTransactions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncreaseDecreaseThroughSharebasedPaymentTransactions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (decrease) through share-based payment transactions, equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForDecreaseIncreaseInOtherOperatingAssetsAndLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">- (De)/Increase in other operating assets/liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForDecreaseIncreaseInOtherOperatingAssetsAndLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments For Decrease Increase In Other Operating Assets And Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForDecreaseIncreaseInOtherOperatingAssetsAndLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjustments for decrease increase in other operating assets and liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_GainsLossesOnExchangeDifferencesOnTranslationBeforeTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gains (losses) on exchange differences on translation of foreign operations, before tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_GainsLossesOnExchangeDifferencesOnTranslationBeforeTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign currency exchange gain (loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ClassesOfPropertyPlantAndEquipmentAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Classes of property, plant and equipment [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ClassesOfPropertyPlantAndEquipmentAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Classes of property, plant and equipment [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PaymentsOfLeaseLiabilitiesClassifiedAsFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments of lease liabilities, classified as financing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PaymentsOfLeaseLiabilitiesClassifiedAsFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Payments of lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PaymentsOfLeaseLiabilitiesClassifiedAsFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Principal payment of lease obligations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NoncurrentLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Non-current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NoncurrentLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NoncurrentLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non-current lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalPeriodFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Fiscal Period Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalPeriodFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Fiscal Period Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfIntangibleAssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of detailed information about intangible assets [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityShellCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Shell Company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityShellCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Shell Company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CurrentBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current Borrowing Capacity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CurrentBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Current borrowing capacity.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CurrentBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current borrowing capacity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PercentageOfReasonablyPossibleDecreaseInActuarialAssumption_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assumptions, decrease</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PercentageOfReasonablyPossibleDecreaseInActuarialAssumption_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage of reasonably possible decrease in actuarial assumption</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PercentageOfReasonablyPossibleDecreaseInActuarialAssumption_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Assumptions, decrease</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercise price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Exercise price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExercisePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Exercise price.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FixedRateOfPreferredDividendDeemedInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fixed rate of preferred dividend deemed interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FixedRateOfPreferredDividendDeemedInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fixed Rate Of Preferred Dividend Deemed Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FixedRateOfPreferredDividendDeemedInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Fixed rate of preferred dividend deemed interest.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DescriptionOfAccountingPolicyOfCashAndCashEquivalentsAndShortTermFinancialAssetsExplanatoryTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and cash equivalents and short-term financial assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DescriptionOfAccountingPolicyOfCashAndCashEquivalentsAndShortTermFinancialAssetsExplanatoryTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description Of Accounting Policy Of Cash and Cash Equivalents and Short-term Financial Assets Explanatory [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DescriptionOfAccountingPolicyOfCashAndCashEquivalentsAndShortTermFinancialAssetsExplanatoryTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Description Of Accounting Policy Of Cash and Cash Equivalents and Short-term Financial Assets Explanatory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashFlowsFromUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash flows from (used in) financing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashFlowsFromUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2009/role/netLabel">Net cash flows from (used in) financing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashFlowsFromUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Decrease in net cash inflow from financing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashFlowsFromUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash inflow for financing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_KeyManagementPersonnelCompensationPostemploymentBenefits_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Pension expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_KeyManagementPersonnelCompensationPostemploymentBenefits_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Key management personnel compensation, post-employment benefits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementStrategyAndGovernanceAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management, Strategy, and Governance [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementPositionsOrCommitteesResponsibleReportToBoardFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Positions or Committees Responsible Report to Board [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskBoardOfDirectorsOversightTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Board of Directors Oversight [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NetDefinedBenefitLiabilityAssetAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net defined benefit liability (asset) [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NetDefinedBenefitLiabilityAssetAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net defined benefit liability (asset) [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IssueOfEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issue of equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OtherCurrentFinancialAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other current assets, excluding prepaids</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OtherCurrentFinancialAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Short-term financial assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OtherCurrentFinancialAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other current financial assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_MaturityAnalysisForNonderivativeFinancialLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of maturity analysis for non-derivative financial liabilities [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_MaturityAnalysisForNonderivativeFinancialLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Financial Instruments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfRangeOfExercisePricesOfOutstandingShareOptionsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of range of exercise prices of outstanding share options [table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PerSharePurchasePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Per share purchase price.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PerSharePurchasePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Per Share Purchase Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PerSharePurchasePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Per share purchase price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_EffectOfExchangeRateChangesOnCashAndCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effect of foreign exchange rate changes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_EffectOfExchangeRateChangesOnCashAndCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effect of exchange rate changes on cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OptionPricingModelMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Option pricing model [member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialAssumptionOfRetirementAge2019_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Retirement age</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SummaryOfMaterialAccountingPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Summary of Material Accounting Policies [Text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SummaryOfMaterialAccountingPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Summary of Material Accounting Policies.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SummaryOfMaterialAccountingPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Material Accounting Policies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_FinanceCosts_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel">Total finance expense</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_FinanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfWarrantsOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number Of Warrants Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfWarrantsOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of warrants outstanding.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfWarrantsOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of warrants outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FairValueGainLossOnWarrantLiability_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Fair value loss on warrant liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FairValueGainLossOnWarrantLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair value loss on warrant liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FairValueGainLossOnWarrantLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Gain Loss on Warrant Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FairValueGainLossOnWarrantLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Fair value gain loss on warrant liability.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PaymentOfObligatedNonRefundableCostContribution_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment of obligated non refundable cost contribution</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PaymentOfObligatedNonRefundableCostContribution_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment Of Obligated Non Refundable Cost Contribution</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PaymentOfObligatedNonRefundableCostContribution_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment of obligated non refundable cost contribution.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CurrentValueAddedTaxReceivablesAndInterestReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current Value Added Tax Receivables And Interest Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CurrentValueAddedTaxReceivablesAndInterestReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Current value added tax receivables and interest receivable.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CurrentValueAddedTaxReceivablesAndInterestReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">VAT, withholding tax and interest receivables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFilerCategory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Filer Category</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdditionalBorrowings_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional borrowings</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncreaseDecreaseThroughExerciseOfWarrantsEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (decrease) through exercise of warrants, equity</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfWhollyOwnedSubsidiaries_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of wholly owned subsidiaries.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_FinancialLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_FinancialLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Financial liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutOptionsExercisable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnout Options Exercisable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutOptionsExercisable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Earnout options exercisable.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutOptionsExercisable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnout options exercisable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognisedIntangibleAsset_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Intangible asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognisedIntangibleAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deductible Temporary Differences For Which No Deferred Tax Asset Is Recognised Intangible Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognisedIntangibleAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deductible temporary differences for which no deferred tax asset is recognised intangible asset.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskThirdPartyOversightAndIdentificationProcessesFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Third Party Oversight and Identification Processes [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EuroCurrencyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Euro</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EuroCurrencyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Euro Currency [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EuroCurrencyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Euro currency.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SupplementalNon-CashInvestingInformationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Supplemental Non-Cash Investing Information.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SupplementalNon-CashInvestingInformationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Supplemental non-cash investing information</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentIncreaseInUSDMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">+5% USD</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentIncreaseInUSDMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Five Percent Increase In U S D [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentIncreaseInUSDMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Five Percent Increase In USD.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageExercisePriceOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted average exercise price of other equity instruments outstanding in share-based payment arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageExercisePriceOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Weighted average exercise price issued and exercised beginning balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageExercisePriceOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Weighted average exercise price issued and exercised ending balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncreaseDecreaseInDefinedBenefitObligationDueToReasonablyPossibleIncreaseInActuarialAssumption_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Decrease/(increase) from actual defined benefit obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncreaseDecreaseInDefinedBenefitObligationDueToReasonablyPossibleIncreaseInActuarialAssumption_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (decrease) in defined benefit obligation due to reasonably possible increase in actuarial assumption</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncreaseDecreaseInDefinedBenefitObligationDueToReasonablyPossibleIncreaseInActuarialAssumption_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Reduction of defined benefit pension liabilities</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LossPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Loss per share [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LossPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loss per share [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LossPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loss per share:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfEarnoutSharesVested_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Dilutive Effect of Earnout Shares Vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfEarnoutSharesVested_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Dilutive effect of earnout shares vested.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfEarnoutSharesVested_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnout shares vested</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementThirdPartyEngagedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Third Party Engaged [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashAndCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashAndCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Cash and cash equivalents, beginning of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashAndCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Cash and cash equivalents, end of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashAndCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashAndCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ProfitLossFromOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Profit (loss) from operating activities</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DirectOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Direct Offering [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DirectOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Direct offering.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DirectOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Direct Offering</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FairValueGainLossOnWarrantLiabilityShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair value loss on warrant liability (Share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FairValueGainLossOnWarrantLiabilityShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Gain Loss on Warrant Liability Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FairValueGainLossOnWarrantLiabilityShare_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Fair value gain loss on warrant liability share.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PresentationOfInterestInTheStatementOfCashFlowsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Presentation Of Interest In The Statement Of Cash Flows Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PresentationOfInterestInTheStatementOfCashFlowsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Presentation of interest in the statement of cash flows&#160;policy.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PresentationOfInterestInTheStatementOfCashFlowsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Presentation of interest in the statement of cash flows</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ProceedsFromIssuingSharesFromConvertibleLoanAgreementInvestors_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from the shares issued to CLA investors</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ProceedsFromIssuingSharesFromConvertibleLoanAgreementInvestors_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds From Issuing Shares From Convertible Loan Agreement Investors</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ProceedsFromIssuingSharesFromConvertibleLoanAgreementInvestors_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Proceeds from issuing shares from convertible loan agreement investors.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">ASSETS</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AggregateAmountOfPaymentsCommitted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate amount of payments committed</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AggregateAmountOfPaymentsCommitted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Aggregate Amount Of Payments Committed</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AggregateAmountOfPaymentsCommitted_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Aggregate amount of payments committed.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfLeasesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">RIGHT-OF-USE ASSETS AND LEASE LIABILITIES</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_SegmentGeographicalDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Geographical [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_StockOptionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Options [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_StockOptionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock Options.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_StockOptionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Options Granted</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CashAndCashEquivalentsAndShortTermFinancialAssetsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash And Cash Equivalents and Short Term Financial Assets [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CashAndCashEquivalentsAndShortTermFinancialAssetsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cash and cash equivalents and short term financial assets.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdditionalShareBasedCompensationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional share based compensation expense</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdditionalShareBasedCompensationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Additional share based compensation expense.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CarryingAmountMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Carrying amount [member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_UsefulLifeMeasuredAsPeriodOfTimePropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property, plant and equipment useful life</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfFinancialInstrumentsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure Of Financial Instruments [Line Items]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OfficeEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Office - IT Tools</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OutstandingShareExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Outstanding Share Expiration Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OutstandingShareExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Outstanding share expiration period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncreaseDecreaseInDefinedBenefitObligationDueToReasonablyPossibleDecreaseInActuarialAssumption_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (decrease) in defined benefit obligation due to reasonably possible decrease in actuarial assumption</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_LeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel">Total</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfDeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognisedExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Of Deductible Temporary Differences For Which No Deferred Tax Asset Is Recognised Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfDeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognisedExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of deductible temporary differences for which no deferred tax asset is recognised explanatory.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IntangibleAssetsOtherThanGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intangible assets other than goodwill</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IntangibleAssetsOtherThanGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConditionalShareCapitalForNewBondsAndSimilarDebtInstrumentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">New Bonds and Similar Debt Instruments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConditionalShareCapitalForNewBondsAndSimilarDebtInstrumentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Conditional Share Capital for New Bonds and Similar Debt Instruments [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConditionalShareCapitalForNewBondsAndSimilarDebtInstrumentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Conditional share capital for new bonds and similar debt instruments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfSensitivityAnalysisForActuarialAssumptionsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure Of Sensitivity Analysis For Actuarial Assumptions [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfSensitivityAnalysisForActuarialAssumptionsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of sensitivity analysis for actuarial assumptions [line items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfGroupEntitiesForConsolidation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of group entities for consolidation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfGroupEntitiesForConsolidation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number Of Group Entities For Consolidation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfGroupEntitiesForConsolidation_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of group entities for consolidation.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConversionOfLegacyOculisLongTermFinancialDebtIntoOculisOrdinarySharesValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Conversion of Legacy Oculis Long-Term Financial Debt Into Oculis Ordinary Shares Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConversionOfLegacyOculisLongTermFinancialDebtIntoOculisOrdinarySharesValue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Conversion of legacy oculis long-term financial debt into oculis ordinary shares value.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConversionOfLegacyOculisLongTermFinancialDebtIntoOculisOrdinarySharesValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion of Legacy Oculis long-term financial debt into Oculis ordinary shares value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncreaseDecreaseThroughExerciseOfOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock option exercised</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfWarrantLiabilitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of Warrant Liabilities [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfWarrantLiabilitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of warrant liabilities abstract.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PercentageOfReasonablyPossibleIncreaseInActuarialAssumption_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assumptions, increase</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PercentageOfReasonablyPossibleIncreaseInActuarialAssumption_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage of reasonably possible increase in actuarial assumption</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_RevenueAndOperatingIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_RevenueAndOperatingIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue and other operating income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_RevenueAndOperatingIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Operating income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentShellCompanyReport_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Shell Company Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentShellCompanyReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Shell Company Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_UnderwrittenOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Underwritten Offering</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_UnderwrittenOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Underwritten Offering [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_UnderwrittenOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Underwritten offering.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ExpenseFromEquitysettledSharebasedPaymentTransactionsInWhichGoodsOrServicesReceivedDidNotQualifyForRecognitionAsAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total share-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ExpenseFromEquitysettledSharebasedPaymentTransactionsInWhichGoodsOrServicesReceivedDidNotQualifyForRecognitionAsAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Expense from equity-settled share-based payment transactions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ExpenseFromEquitysettledSharebasedPaymentTransactionsInWhichGoodsOrServicesReceivedDidNotQualifyForRecognitionAsAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Total share-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of non-adjusting events after reporting period [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ApplicableRateForTwentyTwentySixMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Applicable Rate For Twenty Twenty Six [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ApplicableRateForTwentyTwentySixMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Applicable rate for twenty twenty six.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ApplicableRateForTwentyTwentySixMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2026</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_GrantedSharesExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Granted shares expiration period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_GrantedSharesExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Granted Shares Expiration Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_GrantedSharesExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Granted shares expiration period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of transactions between related parties [line items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FollowOnPublicOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Follow On Public Offering [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FollowOnPublicOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Follow on public offering.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FollowOnPublicOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Follow-on public offering</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AttributionOfExpensesByNatureToTheirFunctionDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Attribution of expenses by nature to their function [domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForForeignCurrencyTranslationExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign currency transactions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForForeignCurrencyTranslationExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description of accounting policy for foreign currency translation [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of non-adjusting events after reporting period [line items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CapitalBand_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Capital band</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CapitalBand_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Capital Band</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CapitalBand_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Capital band.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdjustmentsForDecreaseIncreaseInOtherCurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">- De/(Increase) in other current assets</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfIncomeAndExpensesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">INCOME AND EXPENSES</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfIncomeAndExpensesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of income and expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialAssumptionOfExpectedRatesOfSalaryIncreases_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Future salary increases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialAssumptionOfExpectedRatesOfSalaryIncreases_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Actuarial assumption of expected rates of salary increases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialAssumptionOfExpectedRatesOfSalaryIncreases_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Assumption for future salary increases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CommitmentsRelatedToRennesUniversityCollaborationResearchAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments Related To Rennes University Collaboration Research Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CommitmentsRelatedToRennesUniversityCollaborationResearchAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Commitments related to rennes university collaboration research agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CommitmentsRelatedToRennesUniversityCollaborationResearchAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments Related to Rennes University Collaboration Research Agreement</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfGroupReportableLossesMaturityExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Group Reportable Losses Maturity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfGroupReportableLossesMaturityExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Of Group Reportable Losses Maturity Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfGroupReportableLossesMaturityExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of group reportable losses maturity explanatory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentIncreaseInEuroMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">+5% EUR</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentIncreaseInEuroMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Five percent increase in Euro.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MenMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Men</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MenMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Men [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MenMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Men.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CommitmentsRelatedToAccureLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments Related To Accure License Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CommitmentsRelatedToAccureLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Commitments related to Accure license agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CommitmentsRelatedToAccureLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments Related to Accure License Agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForSegmentReportingExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segment reporting</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Liabilities at end of period</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SummaryOfCashAndCashEquivalentsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">cash and cash equivalents table.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SummaryOfCashAndCashEquivalentsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Cash and Cash Equivalents and Short-Term Financial Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfSharesInConnectionWithReductionToWarrantLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance of Shares in Connection with Reduction to Warrant Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfSharesInConnectionWithReductionToWarrantLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of shares in connection with reduction to warrant liability.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfSharesInConnectionWithReductionToWarrantLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of shares in connection with reduction to warrant liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WarrantsPreviouslyGranted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrants previously granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WarrantsPreviouslyGranted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Previously Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WarrantsPreviouslyGranted_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants Previously Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AccountingEstimatesAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting estimates [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ApplicableTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Applicable tax rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ApplicableTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Applicable tax rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityWellKnownSeasonedIssuer_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Well-known Seasoned Issuer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityWellKnownSeasonedIssuer_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Well-known Seasoned Issuer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WorkingCapitalAdjustmentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Working capital adjustments:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WorkingCapitalAdjustmentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Working Capital Adjustments [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WorkingCapitalAdjustmentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Working capital adjustments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfBasisOfPreparationAndChangesToGroupAccountingPoliciesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of basis of preparation and changes to group accounting policies.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfBasisOfPreparationAndChangesToGroupAccountingPoliciesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Of Basis Of Preparation And Changes To Group Accounting Policies [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfBasisOfPreparationAndChangesToGroupAccountingPoliciesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure Of Basis Of Preparation And Changes To Group Accounting Policies [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_FunctionalOrPresentationCurrencyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Functional or presentation currency [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_FunctionalOrPresentationCurrencyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Functional or presentation currency [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_LiabilitiesArisingFromFinancingActivitiesDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities arising from financing activities [domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PIPEAndCLAFinancingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">PIPE and CLA Financing</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PIPEAndCLAFinancingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">P I P E and C L A Financing [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PIPEAndCLAFinancingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">PIPE and CLA financing.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_UnusedTaxLossesForWhichNoDeferredTaxAssetRecognised_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Tax losses in Switzerland</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_UnusedTaxLossesForWhichNoDeferredTaxAssetRecognised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_UnusedTaxLossesForWhichNoDeferredTaxAssetRecognised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unused tax losses for which no deferred tax asset recognised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncreaseDecreaseInNumberOfOrdinarySharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (decrease) in number of ordinary shares issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncreaseDecreaseInNumberOfOrdinarySharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion of Legacy Oculis ordinary shares and treasury shares into Oculis ordinary shares (in Shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfBusinessCombinationsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of detailed information about business combination [table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdditionsOtherThanThroughBusinessCombinationsPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additions other than through business combinations, property, plant and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdditionsOtherThanThroughBusinessCombinationsPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfComponentsOfNetBenefitExpenseExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Of Components Of Net Benefit Expense Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfComponentsOfNetBenefitExpenseExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of components of net benefit expense explanatory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfComponentsOfNetBenefitExpenseExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Components of Net Benefit Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CommitmentsRelatedToNovartisLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments Related To Novartis License Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CommitmentsRelatedToNovartisLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Commitments related to Novartis license agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CommitmentsRelatedToNovartisLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments Related To Novartis License Agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_RightofuseAssetsIncreaseDecreaseInRevaluationSurplus_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Indexation for the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_RightofuseAssetsIncreaseDecreaseInRevaluationSurplus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Right-of-use assets, increase (decrease) in revaluation surplus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_RightofuseAssetsIncreaseDecreaseInRevaluationSurplus_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Indexation for the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AmendmentFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amendment Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AmendmentFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amendment Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfShareCapitalReservesAndOtherEquityInterestExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shareholders' Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfShareCapitalReservesAndOtherEquityInterestExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of share capital, reserves and other equity interest [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfPropertyPlantAndEquipmentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure Of Property Plant And Equipment [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfPropertyPlantAndEquipmentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of detailed information about property, plant and equipment [line items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WeightedAverageExercisePriceOfShareEarnoutOptionsGrantedInShareBasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average Exercise Price, Earnout Option Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WeightedAverageExercisePriceOfShareEarnoutOptionsGrantedInShareBasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Exercise Price Of Share Earnout Options Granted In Share-based Payment Arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WeightedAverageExercisePriceOfShareEarnoutOptionsGrantedInShareBasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Weighted average exercise price of share earnout options granted in share-based payment arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialGainsLossesArisingFromChangesInDemographicAssumptionsNetOfTaxDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Demographic assumptions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialGainsLossesArisingFromChangesInDemographicAssumptionsNetOfTaxDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Actuarial gains (losses) arising from changes in demographic assumptions, net of tax, defined benefit plans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialGainsLossesArisingFromChangesInDemographicAssumptionsNetOfTaxDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Actuarial gain of defined benefit pension liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_BorrowingsByNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Borrowings by name [domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdministrationCostsNotReflectedInReturnOnPlanAssetsDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Administration cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdministrationCostsNotReflectedInReturnOnPlanAssetsDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Administration costs not reflected in return on plan assets, defined benefit plans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdministrationCostsNotReflectedInReturnOnPlanAssetsDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Administrative expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdministrationCostsNotReflectedInReturnOnPlanAssetsDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Administrative expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdministrationCostsNotReflectedInReturnOnPlanAssetsDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Administration cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CorporateInformationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Corporate information.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CorporateInformationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Corporate Information [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfInformationAboutKeyManagementPersonnelExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Key Management Including Board Of Directors And Executive Management Compensation Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfInformationAboutKeyManagementPersonnelExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of information about key management personnel [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressPostalZipCode_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, Postal Zip Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressPostalZipCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Postal Zip Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DescriptionOfAccountingPolicyOfCapitalizationOfTransactionCostsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Capitalization of transaction costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DescriptionOfAccountingPolicyOfCapitalizationOfTransactionCostsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description Of Accounting Policy Of Capitalization Of Transaction Costs Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DescriptionOfAccountingPolicyOfCapitalizationOfTransactionCostsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Description of accounting policy of capitalization of transaction costs explanatory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CategoriesOfRelatedPartiesDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Categories of related parties [domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfReportingSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of reporting segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfReportingSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number Of Reporting Segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfReportingSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of reporting segments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FixedTermBankDepositsMaturityTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fixed term bank deposits maturity term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FixedTermBankDepositsMaturityTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fixed Term Bank Deposits Maturity Term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FixedTermBankDepositsMaturityTerm_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Fixed term bank deposits maturity term.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOtherCurrentAssetsAndAccruedIncomeAdditionalInformationDetailsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure other current assets and accrued income additional information details.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOtherCurrentAssetsAndAccruedIncomeAdditionalInformationDetailsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure other current assets and accrued income additional information details [table]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_StockAppreciationRightsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">SARs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_StockAppreciationRightsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Appreciation Rights [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_StockAppreciationRightsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock Appreciation Rights.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfOperatingSegmentsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure Of Operating Segments [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfOperatingSegmentsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of operating segments [line items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AggregateMaximumOfferingPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Aggregate Maximum Offering Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AggregateMaximumOfferingPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Aggregate Maximum Offering Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AggregateMaximumOfferingPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate maximum offering price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OrdinarySharePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Ordinary share price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OrdinarySharePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Price of a single ordinary share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OrdinarySharePrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfWarrantExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of warrant exercised</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfWarrantExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of warrant exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, Address Line One</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AccountingEstimatesDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting estimates [domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskMateriallyAffectedOrReasonablyLikelyToMateriallyAffectRegistrantFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Flag]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ProjectManagementFee_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Project management fee</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ProjectManagementFee_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Project Management Fee</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ProjectManagementFee_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Project management fee.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ScheduleOfPotentialDilutiveEffectNotIncludedInCalculationOfDilutedEarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Potentially Dilutive Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ScheduleOfPotentialDilutiveEffectNotIncludedInCalculationOfDilutedEarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Potential Dilutive Effect Not Included In Calculation Of Diluted Earnings Per Share [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ScheduleOfPotentialDilutiveEffectNotIncludedInCalculationOfDilutedEarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of potential dilutive effect not included in calculation of diluted earnings per share.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfDetailedInformationAboutAccruedExpensesAndOtherPayablesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Accrued Expenses and Other Payables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfDetailedInformationAboutAccruedExpensesAndOtherPayablesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Of Detailed Information About Accrued Expenses And Other Payables Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfDetailedInformationAboutAccruedExpensesAndOtherPayablesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of detailed information about accrued expenses and other payables explanatory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConditionalShareCapitalForBCAPublicAndPrivateWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">BCA Public and Private Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConditionalShareCapitalForBCAPublicAndPrivateWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Conditional Share Capital For BCA Public And Private Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConditionalShareCapitalForBCAPublicAndPrivateWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Conditional share capital for BCA public and private warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInAccumulatedTaxLosses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reduced accumulated tax losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInAccumulatedTaxLosses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) In Accumulated Tax Losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInAccumulatedTaxLosses_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase (decrease) in accumulated tax losses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LeaseCommencementDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease Commencement Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LeaseCommencementDate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lease commencement date.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LeaseCommencementDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lease commencement date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskBoardCommitteeOrSubcommitteeResponsibleForOversightTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Board Committee or Subcommittee Responsible for Oversight [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Warrants issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of shares issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of shares issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total number of shares issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionCostsRelatedToRegisteredDirectOffering_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Transaction Costs Related to Registered Direct Offering</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionCostsRelatedToRegisteredDirectOffering_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Transaction costs related to Registered Direct Offering</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionCostsRelatedToRegisteredDirectOffering_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Transaction costs related to Registered Direct Offering</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WarrantsExpirationDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Expiration Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WarrantsExpirationDate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants expiration date.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WarrantsExpirationDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrants expiration date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LoanAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loan Agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LoanAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loan Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LoanAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Loan agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentType_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentType_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AmendedWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amended Warrant [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AmendedWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amended Warrant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AmendedWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amended Warrant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OperatingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Operating expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OperatingExpense_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel">Operating expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OperatingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total Operating Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OperatingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OperatingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Operating expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashFlowsFromUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash flows from (used in) investing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashFlowsFromUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2009/role/netLabel">Net cash flows from (used in) investing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashFlowsFromUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Decrease in net cash outflow from investing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashFlowsFromUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash outflow for investing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCentralIndexKey_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Central Index Key</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCentralIndexKey_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Central Index Key</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskProcessForInformingBoardCommitteeOrSubcommitteeResponsibleForOversightTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Process for Informing Board Committee or Subcommittee Responsible for Oversight [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_LicencesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Licences [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_LicencesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Licences [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_BottomOfRangeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Minimum</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_BottomOfRangeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Bottom of Range</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_BottomOfRangeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Bottom of range [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AtTheMarketOfferingProgramMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">At The Market Offering Program [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AtTheMarketOfferingProgramMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">At the market offering program.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AtTheMarketOfferingProgramMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">At-the-Market Offering Program</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ScheduleOfEstimatedUsefulLivesOfPropertyPlantAndEquipmentExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">The disclosure of estimated useful lives of property plant and equipment explanatory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ScheduleOfEstimatedUsefulLivesOfPropertyPlantAndEquipmentExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Estimated Useful Lives Of Property Plant And Equipment Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ScheduleOfEstimatedUsefulLivesOfPropertyPlantAndEquipmentExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Useful Life of Property Plant and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInWarrantLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase Decrease In Warrant Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInWarrantLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase decrease in warrant liability.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInWarrantLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Decrease of the warrant liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LoansFeePayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loans Fee Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LoansFeePayable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Loans fee payable.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LoansFeePayable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional one-time fee payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="country_CH_lbl" xlink:role="http://www.xbrl.org/2003/role/label">SWITZERLAND</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="country_CH_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Switzerland</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ShareBasedPaymentAwardVestingPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vesting period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ShareBasedPaymentAwardVestingPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Based Payment Award Vesting Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ShareBasedPaymentAwardVestingPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Share based payment award vesting period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PercentageOfDebtToMarketCapRatio_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage Of Debt To Market Cap Ratio</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PercentageOfDebtToMarketCapRatio_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of debt to market cap ratio.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PercentageOfDebtToMarketCapRatio_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of debt to market cap ratio</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_GeographicalAreasAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Geographical areas [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_GeographicalAreasAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Geographical areas [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrentTaxExpenseIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Current income tax expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrentTaxExpenseIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current income tax (expense) / benefit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrentTaxExpenseIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current tax expense (income)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrentTaxExpenseIncome_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Current income tax expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfEarnoutShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnout shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfEarnoutShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Dilutive Effect Of Earnout Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfEarnoutShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Dilutive effect of earnout shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DefinedBenefitPlanApplicableRateForConvertingMandatorySavings_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Applicable rate for converting mandatory savings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DefinedBenefitPlanApplicableRateForConvertingMandatorySavings_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Defined Benefit Plan Applicable Rate For Converting Mandatory Savings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DefinedBenefitPlanApplicableRateForConvertingMandatorySavings_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Defined benefit plan applicable rate for converting mandatory savings.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Transaction costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Transaction Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Transaction costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionCosts_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Transaction costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EffectOfOtherItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effect of other items</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EffectOfOtherItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effect Of Other Items</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EffectOfOtherItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Effect of other items.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RestrictedStockUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted stock units [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RestrictedStockUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Restricted stock units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RestrictedStockUnitsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">RSU</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_KeyManagementPersonnelCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IntangibleAssetsAcquisitionRecordedInAccruedExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Intangible Assets Acquisition Recorded In Accrued Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IntangibleAssetsAcquisitionRecordedInAccruedExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Intangible assets acquisition recorded in accrued expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IntangibleAssetsAcquisitionRecordedInAccruedExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangible assets acquisition recorded in accrued expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_RetainedEarningsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_RetainedEarningsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated losses [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_GrantedStockAppreciationRightsExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Granted SARs expiration period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_GrantedStockAppreciationRightsExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Granted Stock Appreciation Rights Expiration Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_GrantedStockAppreciationRightsExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Granted stock appreciation rights expiration period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFinStmtErrorCorrectionFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Financial Statement Error Correction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFinStmtErrorCorrectionFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Financial Statement Error Correction [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOtherCurrentAssetsAndAccruedIncomeAdditionalInformationDetailsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure Other Current Assets And Accrued Income Additional Information Details Line Items</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOtherCurrentAssetsAndAccruedIncomeAdditionalInformationDetailsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure - Other Current Assets and Accrued Income - Additional Information (Details) [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOtherCurrentAssetsAndAccruedIncomeAdditionalInformationDetailsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Other Current Assets And Accrued Income Additional Information Details [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForFairValueAdjustmentOnWarrantLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">- Fair value adjustment on warrant liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForFairValueAdjustmentOnWarrantLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">- Fair value adjustment on warrant liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForFairValueAdjustmentOnWarrantLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments For Fair Value Adjustment On Warrant Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForFairValueAdjustmentOnWarrantLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjustments For Fair Value Adjustment On Warrant Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseThroughExerciseOfOptionsAndRestrictedShareUnitsReleasedEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock options exercised and RSUs released</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseThroughExerciseOfOptionsAndRestrictedShareUnitsReleasedEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (decrease) through exercise of options and restricted share units released, equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseThroughExerciseOfOptionsAndRestrictedShareUnitsReleasedEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase (decrease) through exercise of options and restricted share units released, equity.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TypesOfRisksDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Types of risks [domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfPrivateWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Private warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfPrivateWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Dilutive Effect Of Private Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfPrivateWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Dilutive effect of private warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfGeographicalAreasTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure Of Geographical Areas [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfGeographicalAreasTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of geographical areas [table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfTradeAndOtherPayablesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Trade Payables, Accrued Expenses and Other Payables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfTradeAndOtherPayablesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of trade and other payables [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PeriodOfReasonablyPossibleIncreaseInActuarialAssumption_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assumptions, period increase</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PeriodOfReasonablyPossibleIncreaseInActuarialAssumption_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Period Of Reasonably Possible Increase In Actuarial Assumption</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PeriodOfReasonablyPossibleIncreaseInActuarialAssumption_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Period of reasonably possible increase in actuarial assumption.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ProceedsFromIssueOfOrdinaryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Total gross proceeds</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ProceedsFromIssueOfOrdinaryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from sale of shares in public offerings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaximumBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maximum Borrowing Capacity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaximumBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Maximum borrowing capacity.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaximumBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maximum borrowing capacity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NoncurrentAssetsOtherThanFinancialInstrumentsDeferredTaxAssetsPostemploymentBenefitAssetsAndRightsArisingUnderInsuranceContracts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non-current assets other than financial instruments, deferred tax assets, post-employment benefit assets, and rights arising under insurance contracts</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NoncurrentAssetsOtherThanFinancialInstrumentsDeferredTaxAssetsPostemploymentBenefitAssetsAndRightsArisingUnderInsuranceContracts_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfOrdinaryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of ordinary shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfOrdinaryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance of Ordinary Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfOrdinaryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of ordinary shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PersonnelExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Personnel Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PersonnelExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Personnel Expenses [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PersonnelExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Personnel expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdditionalUpfrontFeePayableUponReachingMilestone_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional upfront fee payable upon reaching milestone</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdditionalUpfrontFeePayableUponReachingMilestone_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Upfront Fee Payable Upon Reaching Milestone</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdditionalUpfrontFeePayableUponReachingMilestone_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Additional upfront fee payable upon reaching milestone.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CurrentFiscalYearEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current Fiscal Year End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CurrentFiscalYearEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current Fiscal Year End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExpenseByEquitySettledShare-BasedPaymentTransactions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Expense By Equity Settled Share-based Payment Transactions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExpenseByEquitySettledShare-BasedPaymentTransactions_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Expense by equity settled share-based payment transactions.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExpenseByEquitySettledShare-BasedPaymentTransactions_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total share-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForDecreaseIncreaseInPayablesAndAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">- (De)/Increase in payables and accrued liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForDecreaseIncreaseInPayablesAndAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments for Decrease Increase In Payables and Accrued Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForDecreaseIncreaseInPayablesAndAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjustments for decrease increase in payables and accrued liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfContingentLiabilitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of contingent liabilities [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WarrantsIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrants issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WarrantsIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WarrantsIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants issued.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionCostsRelatedToThePublicOfferingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Transaction costs related to the public offering</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionCostsRelatedToThePublicOfferingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Transaction Costs Related to The Public Offering Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionCostsRelatedToThePublicOfferingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Transaction costs related to the public offering value.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectEarnoutOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnout options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectEarnoutOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Dilutive Effect Earnout Options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectEarnoutOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Dilutive effect earnout options.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentDecreaseInHKDMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">-5% HKD</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentDecreaseInHKDMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Five Percent Decrease In H K D [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentDecreaseInHKDMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Five Percent Decrease In HKD.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StatementGeographicalAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Geographical [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfCorporateInformationTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Corporate information.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfCorporateInformationTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Of Corporate Information [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfCorporateInformationTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Corporate Information</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PotentialNumberOfSharesIssuedFromShareBasedPaymentTransactions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Potential number of shares issued from share based payment transactions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PotentialNumberOfSharesIssuedFromShareBasedPaymentTransactions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Potential Number Of Shares Issued From Share Based Payment Transactions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PotentialNumberOfSharesIssuedFromShareBasedPaymentTransactions_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Potential number of shares issued from share based payment transactions.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_SurplusDeficitInPlan_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Surplus (deficit) in plan</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_SurplusDeficitInPlan_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net benefit liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageExercisePriceOfOtherEquityInstrumentsGrantedInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted average exercise price of other equity instruments granted in share-based payment arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageExercisePriceOfOtherEquityInstrumentsGrantedInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average grant date fair value, RSUs granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_FinanceIncomeCost_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Finance result</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_FinanceIncomeCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance income (cost)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NonadjustingEventsAfterReportingPeriodAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non-adjusting events after reporting period [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NonadjustingEventsAfterReportingPeriodAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non-adjusting events after reporting period [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfAssumptionsUsedInTheBlackScholesOptionPricingModelForDeterminingTheFairValueOfTheWarrantsExplanatoryTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of assumptions used in the Black-Scholes option-pricing model for determining the fair value of the warrants explanatory [table text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfAssumptionsUsedInTheBlackScholesOptionPricingModelForDeterminingTheFairValueOfTheWarrantsExplanatoryTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">The disclosure of assumptions used in the Black-Scholes option-pricing model for determining the fair value of the warrants explanatory [table text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfAssumptionsUsedInTheBlackScholesOptionPricingModelForDeterminingTheFairValueOfTheWarrantsExplanatoryTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Fair Value of Warrant Estimated on its Grant Date Using the Black Scholes Option Pricing Model</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WeightedAverageExercisePriceOfShareOptionsVestedSettledInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Exercise Price Of Share Options Vested/Settled In Sharebased Payment Arrangement 2019</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WeightedAverageExercisePriceOfShareOptionsVestedSettledInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Weighted Average Exercise Price Of Share Options Vested/Settled In Sharebased Payment Arrangement 2019.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WeightedAverageExercisePriceOfShareOptionsVestedSettledInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Weighted average grant date fair value (CHF), Vested/Settled</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdditionalPaymentUponMilestonesReached_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Additional payment upon milestones reached.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PotentialIssuanceOfEquityThroughShareBasedPaymentTransactions_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Potential issuance of equity through share based payment transactions.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AtTheMarketOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">At-the-Market Offering Program</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AtTheMarketOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">At-the-Market Offering.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LaboratoryEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Laboratory Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LaboratoryEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Laboratory Equipment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LaboratoryEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Laboratory equipment.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WarrantsIssuedPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Issued Price Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WarrantsIssuedPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants issued price per share.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WarrantsIssuedPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrants issued price per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutOptionsGrantedSharesExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnout options granted expiration period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutOptionsGrantedSharesExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnout Options Granted Shares Expiration Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutOptionsGrantedSharesExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Earnout options granted shares expiration period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfRangeOfExercisePricesOfOutstandingShareOptionsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of range of exercise prices of outstanding share options [line items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LoanThreeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loan Three [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LoanThreeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Loan three.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LoanThreeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loan 3</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AccruedResearchAndDevelopmentExpenseCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product development related expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AccruedResearchAndDevelopmentExpenseCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Research And Development Expense Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AccruedResearchAndDevelopmentExpenseCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued R&amp;D expense Current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AccruedResearchAndDevelopmentExpenseCurrent_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accrued R&amp;D expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForImpairmentOfNonfinancialAssetsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impairment of non-financial assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForImpairmentOfNonfinancialAssetsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description of accounting policy for impairment of non-financial assets [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaturityYearFourMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maturity Year Four [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaturityYearFourMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Maturity year four.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaturityYearFourMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2028</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialAssumptionsDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Actuarial assumptions [domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInNumberOfOrdinarySharesIssuedRelatedToUnderwrittenOfferings_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of ordinary shares related to underwritten offerings (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInNumberOfOrdinarySharesIssuedRelatedToUnderwrittenOfferings_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (decrease) in number of ordinary shares issued related to underwritten offerings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInNumberOfOrdinarySharesIssuedRelatedToUnderwrittenOfferings_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase (decrease) in number of ordinary shares issued related to underwritten offerings.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BCAWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">BCA Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BCAWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">BCA Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BCAWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">BCA Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TreasurySharesHeld_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Treasury shares held</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TreasurySharesHeld_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Treasury Shares Held</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TreasurySharesHeld_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Treasury shares held.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConversionOfLegacyOculisLongTermFinancialDebtIntoOculisOrdinaryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion of Legacy Oculis long-term financial debt into Oculis ordinary shares ( in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConversionOfLegacyOculisLongTermFinancialDebtIntoOculisOrdinaryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Conversion Of Legacy Oculis Long-Term Financial Debt Into Oculis Ordinary Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConversionOfLegacyOculisLongTermFinancialDebtIntoOculisOrdinaryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Conversion of legacy oculis long-term financial debt into oculis ordinary shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfDetailedInformationAboutFinancialInstrumentsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of detailed information about financial instruments [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfDetailedInformationAboutFinancialInstrumentsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Carrying Amounts of Financial Assets and Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_Non-UtilizationFeePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non-utilization Fee Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_Non-UtilizationFeePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Non-utilization fee percent.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_Non-UtilizationFeePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non-utilization fee percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ClassesOfLiabilitiesAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Classes of liabilities [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ClassesOfLiabilitiesAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Classes of liabilities [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ExercisePriceOfOutstandingShareOptions2019_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Exercise prices of the outstanding options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ExercisePriceOfOutstandingShareOptions2019_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Exercise price of outstanding share options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ExercisePriceOfOutstandingShareOptions2019_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercise prices of the outstanding awards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutConsiderationIsSubjectToForfeitureTargetOne_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnout consideration is subject to forfeiture target one</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutConsiderationIsSubjectToForfeitureTargetOne_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnout consideration is subject to forfeiture target one</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutConsiderationIsSubjectToForfeitureTargetOne_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Earnout consideration is subject to forfeiture target one.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_InterestPaidClassifiedAsFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest paid, classified as financing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_InterestPaidClassifiedAsFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Interest paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OtherComprehensiveLossAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Loss [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OtherComprehensiveLossAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Other comprehensive loss.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OtherComprehensiveLossAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other comprehensive income (loss):</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageExercisePriceOfShareOptionsForfeitedInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average Exercise Price, Forfeited</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageExercisePriceOfShareOptionsForfeitedInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted average exercise price of share options forfeited in share-based payment arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExerciseOfPublicAndPrivateWarrantsShare_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Number of warrants exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExerciseOfPublicAndPrivateWarrantsShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercise of public and private warrants (Share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExerciseOfPublicAndPrivateWarrantsShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Exercise Of Public And Private Warrants Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExerciseOfPublicAndPrivateWarrantsShare_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Exercise of public and private warrants share,</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExerciseOfPublicAndPrivateWarrantsShare_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Exercise of public and private warrants (Share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OtherOperatingExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other Operating Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OtherOperatingExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Operating Expenses [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OtherOperatingExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Other operating expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MergerAndListingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amount of merger and listing expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MergerAndListingExpense_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Merger and listing expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MergerAndListingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Merger and listing expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MergerAndListingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Merger and listing expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInGeneralAndAdministrationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Increase (decrease) in general and administration expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInGeneralAndAdministrationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in General and Administration Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInGeneralAndAdministrationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase (decrease) in general and administration expense.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_RangeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Range [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageDurationOfDefinedBenefitObligation2019_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average duration of defined benefit obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageDurationOfDefinedBenefitObligation2019_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted average duration of defined benefit obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_BasicEarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basic Loss per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_BasicEarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Basic earnings per share [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_LaterThanOneYearMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Over one year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_LaterThanOneYearMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Later than one year [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfShareOptionsExercisedInSharebasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of share options exercised in share-based payment arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfShareOptionsExercisedInSharebasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of Options, Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfShareOptionsExercisedInSharebasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Number of Options, Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfShareOptionsExercisedInSharebasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Stock option exercised (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashFlowsFromUsedInInvestingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashFlowsFromUsedInInvestingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash flows from (used in) investing activities [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageExercisePriceOfShareOptionsExercisableInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average Exercise Price, Exercisable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageExercisePriceOfShareOptionsExercisableInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted average exercise price of share options exercisable in share-based payment arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfIndividuals_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Individuals</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfIndividuals_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Numbre of Individual</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PotentialNumberOfSharesIssuedInConnectionWithExerciseOfOptionRightsOrOtherEquityLinkedInstruments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Potential number of shares issued in connection with exercise of option rights or other equity linked instruments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PotentialNumberOfSharesIssuedInConnectionWithExerciseOfOptionRightsOrOtherEquityLinkedInstruments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Potential Number Of Shares Issued In Connection With Exercise Of Option Rights or Other Equity Linked Instruments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PotentialNumberOfSharesIssuedInConnectionWithExerciseOfOptionRightsOrOtherEquityLinkedInstruments_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Potential number of shares issued in connection with exercise of option rights or other equity linked instruments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SwissFrancCurrencyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Swiss Franc</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SwissFrancCurrencyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Swiss Franc Currency [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SwissFrancCurrencyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Swiss Franc currency.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NonRefundableUpfrontFeePaid_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non-refundable upfront fee paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NonRefundableUpfrontFeePaid_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non Refundable Upfront Fee Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NonRefundableUpfrontFeePaid_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Non refundable upfront fee paid.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfCommitmentsAndContingentLiabilitiesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments and Contingencies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfCommitmentsAndContingentLiabilitiesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of commitments and contingent liabilities [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseThroughVestingOfEarnoutSharesEquityShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vesting of earnout shares (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseThroughVestingOfEarnoutSharesEquityShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (decrease) through vesting of earnout shares, equity, shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseThroughVestingOfEarnoutSharesEquityShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase (decrease) through vesting of earnout shares, equity, shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure Of Terms And Conditions Of Sharebased Payment Arrangement [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of terms and conditions of share-based payment arrangement [table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfInstrumentsOtherEquityInstrumentsGranted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of other equity instruments granted in share-based payment arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfInstrumentsOtherEquityInstrumentsGranted_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Number of awards, RSUs granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfInstrumentsOtherEquityInstrumentsGranted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">RSAs granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_EarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings per share [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfAccruedIncomeExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of accrued income explanatory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfAccruedIncomeExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Of Accrued Income Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfAccruedIncomeExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Accrued Income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ClassesOfIntangibleAssetsOtherThanGoodwillDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Classes of intangible assets other than goodwill [domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdjustmentsForIncreaseDecreaseInEmployeeBenefitLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments for increase (decrease) in employee benefit liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdjustmentsForIncreaseDecreaseInEmployeeBenefitLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">- Post-employment (benefits)/ loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FairValueAdjustmentOnWarrantLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Fair value adjustment on warrant liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FairValueAdjustmentOnWarrantLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair value adjustment on warrant liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FairValueAdjustmentOnWarrantLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Adjustment on Warrant Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FairValueAdjustmentOnWarrantLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Fair value adjustment on warrant liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfPropertyPlantAndEquipmentExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of property, plant and equipment [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfPropertyPlantAndEquipmentExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaturityYearEightMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maturity Year Eight [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaturityYearEightMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Maturity Year Eight</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaturityYearEightMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2032</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PercentageOfCommissionOnGrossProceeds_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage Of Commission On Gross Proceeds</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PercentageOfCommissionOnGrossProceeds_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage Of Commission On Gross Proceeds</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PercentageOfCommissionOnGrossProceeds_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of commission on gross proceeds</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdditionsOtherThanThroughBusinessCombinationsIntangibleAssetsOtherThanGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdditionsOtherThanThroughBusinessCombinationsIntangibleAssetsOtherThanGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additions other than through business combinations, intangible assets other than goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdjustmentsForFinanceIncomeCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments for finance income (cost)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdjustmentsForFinanceIncomeCost_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">- Financial result</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutConsiderationIsSubjectToForfeitureTargetTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnout consideration is subject to forfeiture target two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutConsiderationIsSubjectToForfeitureTargetTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnout consideration is subject to forfeiture Target Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutConsiderationIsSubjectToForfeitureTargetTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Earnout consideration is subject to forfeiture Target Two.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfResearchAndDevelopmentCommitmentsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of research and development commitments explanatory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfResearchAndDevelopmentCommitmentsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Of Research And Development Commitments Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfResearchAndDevelopmentCommitmentsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Research and Development Commitments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AccrualDueToClinicalTrialOfMilestones_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">accrual due to clinical trial of milestones</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AccrualDueToClinicalTrialOfMilestones_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrual Due To Clinical Trial Of Milestones</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AccrualDueToClinicalTrialOfMilestones_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrual due to clinical trial of milestones</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RedemptionOptionAmountEquivalentToInvestorsInvestmentAccruedDividendAndCompoundInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Redemption option amount equivalent to investors investment accrued dividend and compound interest rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RedemptionOptionAmountEquivalentToInvestorsInvestmentAccruedDividendAndCompoundInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Redemption Option Amount Equivalent To Investors Investment Accrued Dividend And Compound Interest Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RedemptionOptionAmountEquivalentToInvestorsInvestmentAccruedDividendAndCompoundInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Redemption option amount equivalent To investors investment accrued dividend and compound interest rate.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfSharesInConnectionWithWarrantExercises_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance of Shares in Connection with Warrant Exercises</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfSharesInConnectionWithWarrantExercises_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of shares in connection with warrant exercises.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfSharesInConnectionWithWarrantExercises_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Warrants exercised (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfSharesInConnectionWithWarrantExercises_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of shares in connection with warrant exercises (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ExercisePriceShareOptionsGranted2019_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Exercise price, share options granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ExercisePriceShareOptionsGranted2019_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share price on valuation date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfDetailedInformationAboutPropertyPlantAndEquipmentExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of detailed information about property, plant and equipment [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfDetailedInformationAboutPropertyPlantAndEquipmentExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Book Values of Property and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AuditorFirmId_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Auditor Firm ID</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfBasisOfPreparationAndChangesToGroupAccountingPoliciesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Of Basis Of Preparation And Changes To Group Accounting Policies [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfBasisOfPreparationAndChangesToGroupAccountingPoliciesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of basis of preparation and changes to group accounting policies.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MandatoryRetirementSavingsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Mandatory Retirement Savings [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MandatoryRetirementSavingsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Mandatory retirement savings.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MandatoryRetirementSavingsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Mandatory Retirement Savings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfGeographicalAreasExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segment Information</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfGeographicalAreasExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of geographical areas [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentIncreaseInIslandicKronaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">+5% ISK</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentIncreaseInIslandicKronaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Five Percent Increase In Islandic Krona [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentIncreaseInIslandicKronaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Five percent increase in ISK.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FinancingActivitiesDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Financing Activities Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FinancingActivitiesDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Financing activities disclosure.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PercentageOfCapitalizedTransactionCostsForNewShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of capitalized transaction costs for new shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PercentageOfCapitalizedTransactionCostsForNewShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage of Capitalized Transaction Costs for New Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PercentageOfCapitalizedTransactionCostsForNewShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of capitalized transaction costs for new shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfBlackrockWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Dilutive Effect Of Blackrock Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfBlackrockWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Dilutive Effect Of Blackrock Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfBlackrockWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Blackrock Warrant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_EquityAndLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">TOTAL EQUITY AND LIABILITIES</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_EquityAndLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity and liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdditionsToRightofuseAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additions to right-of-use assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdditionsToRightofuseAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">New leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RestrictedStockUnitsOutstandingShareExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Stock Units Outstanding Share Expiration Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RestrictedStockUnitsOutstandingShareExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Restricted Stock Units Outstanding Share Expiration Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RestrictedStockUnitsOutstandingShareExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Range of expiration dates, Outstanding ending balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementPositionsOrCommitteesResponsibleTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Positions or Committees Responsible [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForRecognitionOfRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Grant income recognition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForRecognitionOfRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description of accounting policy for recognition of revenue [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TypesOfRisksAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Types of risks [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TypesOfRisksAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Types of risks [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfBasisOfPreparationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of Basis of Preparation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfBasisOfPreparationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of basis of preparation.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OtherCountryMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Others</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OtherCountryMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Country [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OtherCountryMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Other country member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_FinanceIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finance income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_FinanceIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finance income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_FinanceIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total finance income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentInformationLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Information [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentInformationLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Information [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdjustmentsForSharebasedPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">- Share-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdjustmentsForSharebasedPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments for share-based payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TreasurySharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Treasury shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TreasurySharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Treasury shares [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NoncurrentFinancialAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non-current financial assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NoncurrentFinancialAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total non-current financial assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NoncurrentFinancialAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Financial assets - non-current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NoncurrentFinancialAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Financial assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ProceedsFromExerciseOfOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from stock options exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ProceedsFromExerciseOfOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from exercise of options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ShareholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shareholders' Equity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ShareholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Shareholders' equity abstract.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FairValueOfWarrantOptionPricingModelLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair value of Warrant Option Pricing model [Line items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FairValueOfWarrantOptionPricingModelLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Fair value of Warrant Option Pricing model.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskProcessForInformingManagementOrCommitteesResponsibleTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Process for Informing Management or Committees Responsible [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_MajorBusinessCombinationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Major business combination [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_MajorBusinessCombinationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnout Consideration Business Combination</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfShareEarnoutOptionsGrantedInShareBasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of Options, Earnout Option Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfShareEarnoutOptionsGrantedInShareBasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number Of Share Earnout Options Granted In Share-based Payment Arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfShareEarnoutOptionsGrantedInShareBasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of share earnout options granted in share-based payment arrangement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DefinedBenefitPlanPlanAssetsInsuranceCoverageParentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Defined benefit plan, plan assets, insurance coverage parentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DefinedBenefitPlanPlanAssetsInsuranceCoverageParentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Defined Benefit Plan Plan Assets Insurance Coverage Parentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DefinedBenefitPlanPlanAssetsInsuranceCoverageParentage_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Defined benefit plan, plan assets, insurance coverage parentage.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DescriptionOfAccountingPolicyOfGroupAccountingExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Group accounting</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DescriptionOfAccountingPolicyOfGroupAccountingExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description Of Accounting Policy Of Group Accounting Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DescriptionOfAccountingPolicyOfGroupAccountingExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Description of accounting policy of group accounting explanatory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForEarningsPerShareExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description of accounting policy for earnings per share [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForEarningsPerShareExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loss per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentRegistrationStatement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Registration Statement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentRegistrationStatement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Registration Statement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ReserveOfSharebasedPaymentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reserve for share-based payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ReserveOfSharebasedPaymentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reserve of share-based payments [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CapitalRequirementsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Capital requirements [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PercentageOfProjectManagementFee_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of project management fee</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PercentageOfProjectManagementFee_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage Of Project Management Fee</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PercentageOfProjectManagementFee_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of project management fee.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OfficeEquipmentAndHardwareMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Office Equipment And Hardware [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OfficeEquipmentAndHardwareMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Office equipment and hardware.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OfficeEquipmentAndHardwareMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Office Equipment and Hardware</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EligibleCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Eligible Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EligibleCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Eligible costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EligibleCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Eligible costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrentLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrentLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Short-term lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrentLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForLeasesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForLeasesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description of accounting policy for leases [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfStockAppreciationRightsGrantedInSharebasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of SARs, Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfStockAppreciationRightsGrantedInSharebasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number Of Stock Appreciation Rights Granted In Sharebased Payment Arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfStockAppreciationRightsGrantedInSharebasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of stock appreciation rights granted in sharebased payment arrangement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CashAndCashEquivalentsAndShortTermFinancialAssetsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash And Cash Equivalents and Short Term Financial Assets [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CashAndCashEquivalentsAndShortTermFinancialAssetsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cash and cash equivalents and short term financial assets.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ClassesOfShareCapitalDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Classes of share capital [domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PotentialNumberOfSharesIssuedInConnectionWithExerciseOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Potential number of shares issued in connection with exercise of warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PotentialNumberOfSharesIssuedInConnectionWithExerciseOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Potential Number Of Shares Issued in Connection with Exercise of Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PotentialNumberOfSharesIssuedInConnectionWithExerciseOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Potential number of shares issued in connection with exercise of warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ShareBasedCompensationPersonnelExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Based Compensation Personnel Expense [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ShareBasedCompensationPersonnelExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Share based compensation personnel expense.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ShareBasedCompensationPersonnelExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share-based Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RedemptionOptionAmountEquivalentToInvestorsInvestmentAccruedDividendAndCompoundInterestAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Redemption option amount equivalent to investors investment accrued dividend and compound interest amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RedemptionOptionAmountEquivalentToInvestorsInvestmentAccruedDividendAndCompoundInterestAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Redemption Option Amount Equivalent To Investors Investment Accrued Dividend And Compound Interest Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RedemptionOptionAmountEquivalentToInvestorsInvestmentAccruedDividendAndCompoundInterestAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Redemption option amount equivalent To investors investment accrued dividend and compound interest amount.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseThroughExerciseOfOptionsAndRestrictedShareUnitsVestedOrReleasedEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock options exercised and RSUs vested/released</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseThroughExerciseOfOptionsAndRestrictedShareUnitsVestedOrReleasedEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (decrease) through exercise of options and restricted share units vested or released, equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseThroughExerciseOfOptionsAndRestrictedShareUnitsVestedOrReleasedEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase (decrease) through exercise of options and restricted share units vested or released, equity.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfWarrantLiabilitiesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrant Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfWarrantLiabilitiesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of Warrant Liabilities Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfWarrantLiabilitiesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of Warrant Liabilities Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_BusinessContactMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business Contact</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_BusinessContactMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Contact [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DefinedBenefitPlansDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Defined benefit plans [domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ApplicableRateForTwentyTwentySevenMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Applicable rate for twenty twenty seven</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ApplicableRateForTwentyTwentySevenMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Applicable Rate For Twenty Twenty Seven[Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ApplicableRateForTwentyTwentySevenMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2027</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfSharebasedPaymentArrangementsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Share-based Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfSharebasedPaymentArrangementsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share Based Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfSharebasedPaymentArrangementsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of share-based payment arrangements [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfDefinedBenefitPlansLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure Of Defined Benefit Plans [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfDefinedBenefitPlansLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of defined benefit plans [line items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfIntangibleAssetsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure Of Intangible Assets [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfIntangibleAssetsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of detailed information about intangible assets [line items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfFinancialInstrumentsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure Of Financial Instruments [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfFinancialInstrumentsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of detailed information about financial instruments [table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RestrictedStockUnitsVestedSettledSharesExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Stock Units Vested/Settled Shares Expiration Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RestrictedStockUnitsVestedSettledSharesExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Restricted Stock Units Vested/Settled Shares Expiration Period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RestrictedStockUnitsVestedSettledSharesExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Range of expiration dates, RSUs vested/settled</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SubscriptionPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Subscription price per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SubscriptionPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subscription Price Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SubscriptionPricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Subscription price per share.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of terms and conditions of share-based payment arrangement [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ActuarialAssumptionOfDemographicAssumptions_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Actuarial assumption of demographic assumptions.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ActuarialAssumptionOfDemographicAssumptions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Actuarial assumption of demographic assumptions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ActuarialAssumptionOfDemographicAssumptions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Demographic assumptions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ReserveOfExchangeDifferencesOnTranslationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cumulative translation adjustment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ReserveOfExchangeDifferencesOnTranslationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cumulative translation adjustment [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="country_US_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">U.S</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="country_US_lbl" xlink:role="http://www.xbrl.org/2003/role/label">UNITED STATES</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ClassesOfShareCapitalAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Classes of share capital [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ClassesOfShareCapitalAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Classes of share capital [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TypesOfSharebasedPaymentArrangementsDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Types of share-based payment arrangements [domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TradeAndOtherCurrentPayables_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Trade payables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TradeAndOtherCurrentPayables_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trade and other current payables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TradeAndOtherCurrentPayables_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total trade and other current payables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TradeAndOtherCurrentPayables_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Trade payables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfDefinedBenefitPlansExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of defined benefit plans [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfDefinedBenefitPlansExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Pensions and Other Post Employment Benefit Plans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExercisedSharesExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Exercised shares expiration period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExercisedSharesExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Exercised Shares Expiration Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExercisedSharesExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercised shares expiration period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfDefinedBenefitPlansTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure Of Defined Benefit Plans [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfDefinedBenefitPlansTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of defined benefit plans [table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LoanOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loan One [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LoanOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Loan one.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LoanOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loan 1</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdjustmentsForInterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">- Interest expense on Series B and C preferred shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdjustmentsForInterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments for interest expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SubsequentEventAfterReportingPeriodMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event After Reporting Period [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SubsequentEventAfterReportingPeriodMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Subsequent event after reporting period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SubsequentEventAfterReportingPeriodMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Event After Reporting Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutConsiderationSharePriceTargetThree_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Earnout consideration share price target three.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutConsiderationSharePriceTargetThree_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share price target three</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutConsiderationSharePriceTargetThree_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnout consideration share price target Three</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ShareIssueRelatedCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share issue related cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ShareIssueRelatedCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Transaction costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ShareIssueRelatedCost_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Transaction costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForWarrantsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrant liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForWarrantsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description of accounting policy for warrants [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForFairValueMeasurementExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair value measurements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForFairValueMeasurementExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description of accounting policy for fair value measurement [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_InterestExpenseOnLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest expense on lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_InterestExpenseOnLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Interest expense for the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_InterestExpenseOnLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">- Interest on lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_InterestExpenseOnLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Interest calculated on leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialAssumptionOfDiscountRatesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Actuarial assumption of discount rates [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialAssumptionOfDiscountRatesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Discount Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrentFinancialAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Short-term financial assets</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrentFinancialAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total current financial assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MergerAndListingExpenseOperatingExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Merger and Listing Expense Operating Expenses Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MergerAndListingExpenseOperatingExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Merger and listing eExpense operating expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MergerAndListingExpenseOperatingExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Merger and listing expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseThroughTreasuryShareTransactionsShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) Through Treasury Share Transactions, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseThroughTreasuryShareTransactionsShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase (decrease) through treasury share transactions, shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseThroughTreasuryShareTransactionsShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of shares to be held as treasury shares (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskMateriallyAffectedOrReasonablyLikelyToMateriallyAffectRegistrantTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AccruedIncomeFxRevaluation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign exchange revaluation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AccruedIncomeFxRevaluation_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued income FX revaluation.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AccruedIncomeFxRevaluation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Income FX Revaluation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_GainsLossesOnExchangeDifferencesOnTranslationNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign currency translation differences</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_GainsLossesOnExchangeDifferencesOnTranslationNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gains (losses) on exchange differences on translation of foreign operations, net of tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementExpertiseOfManagementResponsibleTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Expertise of Management Responsible [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageSharePrice2019_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average grant date fair value of SARs granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageSharePrice2019_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted average share price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfSharesInConnectionWithIncreaseInCash_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of Shares in connection with increase in cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfSharesInConnectionWithIncreaseInCash_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance Of Shares In Connection With Increase In Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfSharesInConnectionWithIncreaseInCash_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of shares in connection with increase in cash.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfFinanceIncomeExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Finance Income</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ExplanationOfEffectOfSharebasedPaymentsOnFinancialPositions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Explanation of effect of share-based payments on entity's financial position [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ExplanationOfEffectOfSharebasedPaymentsOnFinancialPositions_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Summary of Details of Share-Based Compensation Expense by Award</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncreaseDecreaseThroughTreasuryShareTransactions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of shares to be held as treasury shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncreaseDecreaseThroughTreasuryShareTransactions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (decrease) through treasury share transactions, equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ContributionsToPlanByEmployerNetDefinedBenefitLiabilityAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contributions by employer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ContributionsToPlanByEmployerNetDefinedBenefitLiabilityAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Decrease (increase) in net defined benefit liability (asset) resulting from resulting from contributions to plan by employer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ContributionsToPlanByEmployerNetDefinedBenefitLiabilityAsset_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Increase (decrease) in net defined benefit liability (asset) resulting from contributions to plan by employer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_SharePremium_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share premium</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_SharePremium_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share premium</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfEventsAfterReportingPeriodExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of events after reporting period [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfEventsAfterReportingPeriodExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Events</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfShareOptionsExercisableInSharebasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of Options, Exercisable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfShareOptionsExercisableInSharebasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of share options exercisable in share-based payment arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WeightedAverageRemainingContractualLifeOfOtherEquityInstrumentsOutstandingInShareBasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average remaining contractual life of SARs outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WeightedAverageRemainingContractualLifeOfOtherEquityInstrumentsOutstandingInShareBasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted average remaining contractual life of other equity instruments outstanding in share-based payment arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WeightedAverageRemainingContractualLifeOfOtherEquityInstrumentsOutstandingInShareBasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Weighted average remaining contractual life of other equity instruments outstanding in share-based payment arrangement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RestrictedStockAwardsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Stock Awards [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RestrictedStockAwardsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Restricted stock awards.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RestrictedStockAwardsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted Stock Awards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfGeographicalAreasAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of geographical areas [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfOutstandingShareOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Number of Options, Outstanding beginning balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfOutstandingShareOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Number of Options, Outstanding ending balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfOutstandingShareOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of share options outstanding in share-based payment arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressCityOrTown_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, City or Town</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressCityOrTown_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, City or Town</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdditionOfLease_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Addition of Lease</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdditionOfLease_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Addition of lease.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdditionOfLease_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Addition of lease</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DescriptionOfAccountingPolicyForEarnoutConsiderationTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnout consideration</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DescriptionOfAccountingPolicyForEarnoutConsiderationTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description of accounting policy for earnout consideration [Text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DescriptionOfAccountingPolicyForEarnoutConsiderationTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Description of accounting policy for earnout consideration.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TradeAndOtherCurrentPayablesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trade and other current payables [abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NoncurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non-current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_SecurityExchangeName_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Security Exchange Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_SecurityExchangeName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Security Exchange Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentDecreaseInIslandicKronaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">-5% ISK</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentDecreaseInIslandicKronaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Five Percent Decrease In Islandic Krona [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentDecreaseInIslandicKronaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Five percent decrease in ISK.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_ContactPersonnelName_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contact Personnel Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_ContactPersonnelName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contact Personnel Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TaxesAtWeightedAverageIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Taxes at weighted average income tax.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TaxesAtWeightedAverageIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Taxes at Weighted Average Income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TaxesAtWeightedAverageIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Taxes at weighted average income tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfChangesInAccountingEstimatesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of changes in accounting estimates [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdjustmentsForDecreaseIncreaseInAccruedIncomeOtherThanContractAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">- De/(Increase) in accrued income</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfInformationAboutDefinedBenefitPlansAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of information about defined benefit plans [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CancellationOfTreasuryShares1_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Treasury shares cancelled</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CancellationOfTreasuryShares1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cancellation of treasury shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CancellationOfTreasuryShares1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cancellation of treasury shares1</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CancellationOfTreasuryShares1_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cancellation of treasury shares1</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfClassesOfShareCapitalLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of classes of share capital [line items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WeightedAverageExercisePriceOfStockAppreciationRightsGrantedInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average Exercise Price of SARs, Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WeightedAverageExercisePriceOfStockAppreciationRightsGrantedInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Exercise Price Of Stock Appreciation Rights Granted In Sharebased Payment Arrangement 2019</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WeightedAverageExercisePriceOfStockAppreciationRightsGrantedInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Weighted average exercise price of stock appreciation rights granted In sharebased payment arrangement 2019.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ReclassificationAdjustmentsOnForeignCurrencyTranslationDifferencesRecycling_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Foreign currency translation differences recycling</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ReclassificationAdjustmentsOnForeignCurrencyTranslationDifferencesRecycling_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reclassification of foreign exchange impact</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ReclassificationAdjustmentsOnForeignCurrencyTranslationDifferencesRecycling_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Foreign currency translation differences recycling</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ReclassificationAdjustmentsOnForeignCurrencyTranslationDifferencesRecycling_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reclassification adjustments on foreign currency translation differences recycling</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ReclassificationAdjustmentsOnForeignCurrencyTranslationDifferencesRecycling_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Reclassification adjustments on foreign currency translation differences recycling.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrencyInWhichInformationIsDisplayedAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Currency in which information is displayed [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrencyInWhichInformationIsDisplayedAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Currency in which information is displayed [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_StatementOfChangesInEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of changes in equity [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ProfitLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Loss for the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ProfitLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loss for the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ProfitLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Profit (loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ProfitLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net loss for the period attributable to Oculis shareholders</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfShareOptionsExercisedAndRestrictedShareUnitsVestedOrReleased_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock options exercised and RSUs vested/released (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfShareOptionsExercisedAndRestrictedShareUnitsVestedOrReleased_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Share Options Exercised and Restricted Share Units Vested Or Released</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfShareOptionsExercisedAndRestrictedShareUnitsVestedOrReleased_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of share options exercised and restricted share units vested or released.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BoardOfDirectorsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Board of directors [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BoardOfDirectorsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Board of directors</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BoardOfDirectorsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Board of directors</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statistical Measurement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statistical Measurement [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OperatingExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OperatingExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Expenses [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OperatingExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Operating expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentPeriodEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Period End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentPeriodEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Period End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OtherCurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Other current assets, excluding prepaids</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OtherCurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OtherCurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OtherCurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_IcfrAuditorAttestationFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">ICFR Auditor Attestation Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_IcfrAuditorAttestationFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">ICFR Auditor Attestation Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CategoriesOfRelatedPartiesAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Categories of related parties [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LeaseLiabilitiesForeignCurrencyRevaluation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">FX revaluation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LeaseLiabilitiesForeignCurrencyRevaluation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease Liabilities Foreign Currency Revaluation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LeaseLiabilitiesForeignCurrencyRevaluation_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Lease liabilities, foreign currency revaluation.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfRetroactivelyRestatedNumberOfSharesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure of Retroactively Restated Number of Shares Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfRetroactivelyRestatedNumberOfSharesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of Retroactively Restated Number of Shares Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfRetroactivelyRestatedNumberOfSharesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of retroactively restated number of shares explanatory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExternalServiceProvidersOperatingExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">External Service Providers Operating Expenses [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExternalServiceProvidersOperatingExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">External service providers operating expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExternalServiceProvidersOperatingExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">External Service Providers</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of non-adjusting events after reporting period [table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_USDollarCurrencyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">US Dollar</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_USDollarCurrencyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">U S Dollar Currency [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_USDollarCurrencyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">US Dollar currency.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_RightofuseAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Right-of-use assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_RightofuseAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Balance as of January 1,</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_RightofuseAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Balance as of December 31,</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_RightofuseAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Right-of-use assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfOutstandingWarrantsShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number Of Outstanding Warrants Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfOutstandingWarrantsShare_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of outstanding warrants share.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfOutstandingWarrantsShare_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Number of outstanding warrants, Ending Balance (Share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfOutstandingWarrantsShare_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Number of outstanding warrants, Beginning Balance (Share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfCommonStockUponExerciseOfPublicWarrantsPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercise of public warrants per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfCommonStockUponExerciseOfPublicWarrantsPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance Of Common Stock Upon Exercise Of Public Warrants Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfCommonStockUponExerciseOfPublicWarrantsPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of common stock upon exercise of public warrants per share.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IssuedCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IssuedCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issued capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IssuedCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total issued capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NoncurrentRecognisedLiabilitiesDefinedBenefitPlan_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non-current net defined benefit liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NoncurrentRecognisedLiabilitiesDefinedBenefitPlan_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Defined benefit pension liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncomeTaxExpenseContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total tax expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncomeTaxExpenseContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income tax expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncomeTaxExpenseContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tax expense (income)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncomeTaxExpenseContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Tax income (expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncomeTaxExpenseContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Income tax benefit (expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncomeTaxExpenseContinuingOperations_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel">Total tax benefit (expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConvertibleLoanAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">CLA</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConvertibleLoanAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Convertible loan agreements.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConvertibleLoanAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Loan Agreements [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfCashAndCashEquivalentsAndShortTermFinancialAssetsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and Cash Equivalents and Short-Term Financial Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfCashAndCashEquivalentsAndShortTermFinancialAssetsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Of Cash And Cash Equivalents and Short Term Financial Assets Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfCashAndCashEquivalentsAndShortTermFinancialAssetsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of cash and cash equivalents and short term financial assets explanatory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CommitmentsForExternalResearchProjectsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CommitmentsForExternalResearchProjectsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments for external research projects net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CommitmentsForExternalResearchProjectsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments For External Research Projects Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CommitmentsForExternalResearchProjectsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Commitments for external research projects net.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PotentialNumberOfSharesIssuedFromConversionOfDebtInstruments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Potential number of shares issued from conversion of debt instruments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PotentialNumberOfSharesIssuedFromConversionOfDebtInstruments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Potential Number Of Shares Issued From Conversion Of Debt Instruments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PotentialNumberOfSharesIssuedFromConversionOfDebtInstruments_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Potential number of shares issued from conversion of debt instruments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfShareCapitalSharePremiumAndTreasurySharesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Of Share Capital Share Premium And Treasury Shares [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfShareCapitalSharePremiumAndTreasurySharesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of share capital, share premium and treasury shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PeriodOfReasonablyPossibleDecreaseInActuarialAssumption_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assumptions, period decrease</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PeriodOfReasonablyPossibleDecreaseInActuarialAssumption_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Period Of Reasonably Possible Decrease In Actuarial Assumption</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PeriodOfReasonablyPossibleDecreaseInActuarialAssumption_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Period of reasonably possible decrease in actuarial assumption.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementStrategyAndGovernanceLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management, Strategy, and Governance [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BusinessCombinationAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">BCA</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BusinessCombinationAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BusinessCombinationAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combination agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfFairValueOfPlanAssetsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Changes in the Fair Value of Plan Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfFairValueOfPlanAssetsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of fair value of plan assets [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AmortisationIntangibleAssetsOtherThanGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortization charge</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AmortisationIntangibleAssetsOtherThanGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortisation, intangible assets other than goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AmortisationIntangibleAssetsOtherThanGoodwill_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Amortisation, intangible assets other than goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConditionalShareCapitalForEarnoutOptionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnout Options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConditionalShareCapitalForEarnoutOptionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Conditional Share Capital For Earnout Options [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConditionalShareCapitalForEarnoutOptionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Conditional share capital for earnout options.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInProfitLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lower/higher of net loss</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MilestonePaymentsDueUponTrial_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Milestone Payments Due Upon Trial</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MilestonePaymentsDueUponTrial_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Milestone payments due upon trial.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MilestonePaymentsDueUponTrial_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Milestone payments due upon trial</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ExpectedDividendAsPercentageShareOptionsGranted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Divdend yield</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NominalValueOfTreasuryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Nominal Value Of Treasury Shares</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_StatementThatThereWereNoTransfersBetweenLevel1Level2OrLevel3OfFairValueHierarchyEntitysOwnEquityInstruments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Transfers between levels</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_StatementThatThereWereNoTransfersBetweenLevel1Level2OrLevel3OfFairValueHierarchyEntitysOwnEquityInstruments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement that there were no transfers between Level 1, Level 2 or Level 3 of fair value hierarchy, entity's own equity instruments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageSharePriceShareOptionsGranted2019_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average share price at the date of grant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageSharePriceShareOptionsGranted2019_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Weighted average grant date fair value per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageSharePriceShareOptionsGranted2019_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted average share price, share options granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfBasisOfPreparationAndChangesToGroupAccountingPoliciesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure of Basis of Preparation [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfBasisOfPreparationAndChangesToGroupAccountingPoliciesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Of Basis Of Preparation And Changes To Group Accounting Policies [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfBasisOfPreparationAndChangesToGroupAccountingPoliciesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of basis of preparation and changes to group accounting policies.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PublicOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Public offering [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PublicOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Public Offering</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PublicOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Public offering [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FutureTemporaryDifferenceBetweenStatutoryAndCarryingValuesOfTransferredIntangibleAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Future Temporary Difference Between Statutory and Carrying Values of Transferred Intangible Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FutureTemporaryDifferenceBetweenStatutoryAndCarryingValuesOfTransferredIntangibleAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Future temporary difference between statutory and carrying values of transferred intangible asset.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FutureTemporaryDifferenceBetweenStatutoryAndCarryingValuesOfTransferredIntangibleAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Future temporary difference</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of detailed information about borrowings [table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfOtherCurrentAssetsAndOtherReceivablesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Of Other Current Assets and Other Receivables Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfOtherCurrentAssetsAndOtherReceivablesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure of Other Current Assets and Other Receivables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfOtherCurrentAssetsAndOtherReceivablesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of other current assets and other receivables Explanatory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFileNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity File Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFileNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity File Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ReimbursedCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reimbursed costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ReimbursedCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reimbursed Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ReimbursedCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Reimbursed costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_SensitivityAnalysisForEachTypeOfMarketRisk_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Sensitivity Changes in Exchange Rate</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RestrictedStockUnitsGrantedSharesExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Stock Units Granted Shares Expiration Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RestrictedStockUnitsGrantedSharesExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Restricted Stock Units Granted Shares Expiration Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RestrictedStockUnitsGrantedSharesExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Range of expiration dates, RSUs granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CoverAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cover</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CoverAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cover [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WarrantLiabilitiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrant Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WarrantLiabilitiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrant Liabilities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WarrantLiabilitiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrant Liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IssuedCapitalOrdinaryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issued capital of ordinary shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IssuedCapitalOrdinaryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issued capital, ordinary shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfQuantitativeInformationAboutRightofuseAssetsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of quantitative information about right-of-use assets [line items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfNumberAndWeightedAverageExercisePricesOfOtherEquityInstrumentsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of number and weighted average exercise prices of other equity instruments [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfNumberAndWeightedAverageExercisePricesOfOtherEquityInstrumentsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Number and Weighted Average Exercise Prices of Restricted Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfPrincipalAssumptionsUsedForDeterminingPensionBenefitObligationsForGroupPlanExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Principal Assumptions used in Determining Pension Benefit Obligations for Group's Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfPrincipalAssumptionsUsedForDeterminingPensionBenefitObligationsForGroupPlanExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Of Principal Assumptions Used For Determining Pension Benefit Obligations For Group Plan Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfPrincipalAssumptionsUsedForDeterminingPensionBenefitObligationsForGroupPlanExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of principal assumptions used for determining pension benefit obligations for group plan explanatory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ComponentsOfOtherComprehensiveIncomeThatWillNotBeReclassifiedToProfitOrLossNetOfTaxAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Components of other comprehensive income that will not be reclassified to profit or loss, net of tax [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ComponentsOfOtherComprehensiveIncomeThatWillNotBeReclassifiedToProfitOrLossNetOfTaxAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Items that will not be reclassified to Statements of Loss:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForEmployeeBenefitsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee benefits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForEmployeeBenefitsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description of accounting policy for employee benefits [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OtherComprehensiveIncomeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other comprehensive income [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OtherComprehensiveIncomeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other comprehensive income (loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfReconciliationOfAccountingProfitMultipliedByApplicableTaxRatesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Reconciliation of Profit (Loss) Multiplied by Weighted Average Applicable Tax Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfReconciliationOfAccountingProfitMultipliedByApplicableTaxRatesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Of Reconciliation Of Accounting Profit Multiplied By Applicable Tax Rates Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfReconciliationOfAccountingProfitMultipliedByApplicableTaxRatesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of reconciliation of accounting profit multiplied by applicable tax rates explanatory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfRelatedPartyExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">RELATED PARTY DISCLOSURES</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrentLiabilitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current liabilities [abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Carrying amount, accumulated depreciation, amortisation and impairment and gross carrying amount [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CapitalBandMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Capital Band</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CapitalBandMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Capital Band [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CapitalBandMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Capital Band.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ReclassificationAdjustmentsOnExchangeDifferencesOnTranslationNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reclassification adjustments on exchange differences on translation of foreign operations, net of tax</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfUnvestedEarnoutShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unvested earnout shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfUnvestedEarnoutShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Dilutive effect of unvested earnout shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfUnvestedEarnoutShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Dilutive effect of unvested earnout shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NetDefinedBenefitLiabilityAssetDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net defined benefit liability (asset) [domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfNumberAndWeightedAverageExercisePricesOfShareOptionsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of number and weighted average exercise prices of share options [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfNumberAndWeightedAverageExercisePricesOfShareOptionsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Stock Option and SARs Activity under 2023 Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ReturnOnPlanAssetsNetDefinedBenefitLiabilityAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected return</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ReturnOnPlanAssetsNetDefinedBenefitLiabilityAsset_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Increase (decrease) in net defined benefit liability (asset) resulting from return on plan assets excluding interest income or expense</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfEarningsPerShareExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loss Per Share</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ActuarialGainLossOnPostEmploymentBenefitObligationsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Actuarial gain (loss) on post employment benefit obligations.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ActuarialGainLossOnPostEmploymentBenefitObligationsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Actuarial gain (loss) on post-employment benefit obligations [member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AccruedIncomeRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Income Recognized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AccruedIncomeRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued income recognized.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInPotentialDefinedBenefitObligationDueToReasonablyPossibleIncreaseInActuarialAssumption_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase (decrease) in potential defined benefit obligation due to reasonably possible increase in actuarial assumption.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInPotentialDefinedBenefitObligationDueToReasonablyPossibleIncreaseInActuarialAssumption_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (decrease) in potential defined benefit obligation due to reasonably possible increase in actuarial assumption</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInPotentialDefinedBenefitObligationDueToReasonablyPossibleIncreaseInActuarialAssumption_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Potential defined benefit obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning Balance (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending Balance (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Number of shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConditionalShareCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conditional Capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConditionalShareCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Conditional Share Capital [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConditionalShareCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Conditional share capital.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfFinancingActivitiesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Of Financing Activities Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfFinancingActivitiesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of financing activities explanatory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfFinancingActivitiesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Financing Activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncomeAndExpensesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income And Expenses [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncomeAndExpensesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income And Expenses [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncomeAndExpensesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Income and expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure Of Terms And Conditions Of Sharebased Payment Arrangement [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of terms and conditions of share-based payment arrangement [line items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfRetroactivelyRestatedNumberOfSharesExplanatoryAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of Retroactively Restated Number of Shares Explanatory [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfRetroactivelyRestatedNumberOfSharesExplanatoryAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of retroactively restated number of shares explanatory abstract.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OfficeEquipmentHardwareMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Office Equipment &amp; Hardware</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OfficeEquipmentHardwareMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Office Equipment Hardware [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OfficeEquipmentHardwareMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Office equipment &amp; hardware.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ClassAOrdinarySharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Class A Ordinary Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ClassAOrdinarySharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class A Ordinary Shares [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ClassAOrdinarySharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Class A Ordinary Shares [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseThroughVestingOfEarnoutSharesEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (decrease) through vesting of earnout shares, equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseThroughVestingOfEarnoutSharesEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase (decrease) through vesting of earnout shares, equity.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseThroughVestingOfEarnoutSharesEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vesting of earnout shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DefinedBenefitObligationAtPresentValue_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Defined benefit obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DefinedBenefitObligationAtPresentValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Defined benefit obligation, at present value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DefinedBenefitObligationAtPresentValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Defined benefit obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DefinedBenefitObligationAtPresentValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Defined benefit obligation at December 31,</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DefinedBenefitObligationAtPresentValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Defined benefit obligation at 1 January</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DefinedBenefitObligationAtPresentValue_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedPeriodEndLabel">Defined benefit obligation at December 31,</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DefinedBenefitObligationAtPresentValue_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedPeriodStartLabel">Defined benefit obligation at 1 January</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CapitalRequirementsDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Capital requirements [domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConditionalShareCapitalInConnectionWithEmployeeBenefitPlansMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Employee Benefit Plans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConditionalShareCapitalInConnectionWithEmployeeBenefitPlansMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Conditional Share Capital in Connection With Employee Benefit Plans [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConditionalShareCapitalInConnectionWithEmployeeBenefitPlansMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Conditional share capital in connection with employee benefit plans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ListedPriceOfWarrantsPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Listed price of warrants percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ListedPriceOfWarrantsPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Listed Price of Warrants Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ListedPriceOfWarrantsPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Listed price of warrants percentage.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DilutedEarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Diluted Loss per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DilutedEarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Diluted earnings per share [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_GainsLossesOnExchangeDifferencesOnTranslationRecognisedInProfitOrLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Foreign currency exchange gain (loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_GainsLossesOnExchangeDifferencesOnTranslationRecognisedInProfitOrLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Currency exchange gain (loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_GainsLossesOnExchangeDifferencesOnTranslationRecognisedInProfitOrLoss_lbl" xlink:role="http://www.xbrl.org/2009/role/netLabel">Net foreign exchange gain (loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_GainsLossesOnExchangeDifferencesOnTranslationRecognisedInProfitOrLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Impact on loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementProcessesIntegratedFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Processes Integrated [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfRiskFreeInterestRateShareOptionsGranted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Range of risk-free interest rates</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfRiskFreeInterestRateShareOptionsGranted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Risk free interest rate, share options granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfRiskFreeInterestRateShareOptionsGranted_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Risk-free interest rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentTransitionReport_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Transition Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentTransitionReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Transition Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForFinancialInstrumentsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Financial instruments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForFinancialInstrumentsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description of accounting policy for financial instruments [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncomeStatementAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Profit or loss [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_StatementOfFinancialPositionAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of financial position [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DeferredTaxExpenseIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Deferred tax income (expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DeferredTaxExpenseIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred tax (expense) / income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DeferredTaxExpenseIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred tax expense (income)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DeferredTaxExpenseIncome_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Deferred tax income (expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PercentageOfCommission_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of commission</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PercentageOfCommission_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage Of Commission</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PercentageOfCommission_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of commission.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfDetailedInformationAboutBusinessCombinationsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Fair Value of Equity Consideration Issued and Net Assets of Business Combination</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfDetailedInformationAboutBusinessCombinationsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of detailed information about business combination [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DefinedBenefitPlanApplicableRateForConvertingSupplementarySavings_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Applicable rate for converting supplementary savings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DefinedBenefitPlanApplicableRateForConvertingSupplementarySavings_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Defined Benefit Plan Applicable Rate For Converting Supplementary Savings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DefinedBenefitPlanApplicableRateForConvertingSupplementarySavings_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Defined benefit plan applicable rate for converting supplementary savings.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrentAssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrentAssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current assets [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OtherComprehensiveIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other comprehensive income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OtherComprehensiveIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sub-total other comprehensive profit (loss) for the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OtherComprehensiveIncome_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other comprehensive income (loss) for the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdditionsToLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additions to Lease Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdditionsToLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Additions to lease liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdditionsToLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">New leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ClassesOfAssetsDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Classes of assets [domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageExercisePriceOfShareOptionsGrantedInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average Exercise Price, Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageExercisePriceOfShareOptionsGrantedInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted average exercise price of share options granted in share-based payment arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ComponentsOfEquityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Components of equity [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ComponentsOfEquityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Components of equity [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfAssumedWarrantsShare_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Issuance of assumed warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfAssumedWarrantsShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance of Assumed Warrants Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfAssumedWarrantsShare_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of assumed warrants share.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfAssumedWarrantsShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of warrants (Share)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfSummaryOfRestrictedStockUnitActivityUnderEmployeeStockOptionPlanExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Summary of Restricted Stock Unit Activity Under 2023 Plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfSummaryOfRestrictedStockUnitActivityUnderEmployeeStockOptionPlanExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of Summary of Restricted Stock Unit Activity Under Employee Stock Option Plan Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfSummaryOfRestrictedStockUnitActivityUnderEmployeeStockOptionPlanExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of Summary of Restricted Stock Unit Activity Under Employee Stock Option Plan Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_BasicEarningsLossPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Basic earnings (loss) per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_BasicEarningsLossPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total basic earnings (loss) per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_BasicEarningsLossPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basic net loss per share for the period, in CHF</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_BasicEarningsLossPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Basic, loss attributable to equity holders</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementProcessesIntegratedTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Processes Integrated [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_BusinessCombinationsDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business combinations [domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OtherComprehensiveIncomeNetOfTaxGainsLossesOnRemeasurementsOfDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other comprehensive income, net of tax, gains (losses) on remeasurements of defined benefit plans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OtherComprehensiveIncomeNetOfTaxGainsLossesOnRemeasurementsOfDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AttributionOfExpensesByNatureToTheirFunctionAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Attribution of expenses by nature to their function [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ScheduleOfMergerAndListingTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of merger and listing expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ScheduleOfMergerAndListingTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Merger And Listing Table Text Block</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ScheduleOfMergerAndListingTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of merger and listing table text block.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForPropertyPlantAndEquipmentExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForPropertyPlantAndEquipmentExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description of accounting policy for property, plant and equipment [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_BusinessCombinationsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Business combinations [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_BusinessCombinationsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business combinations [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_MaturityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maturity [domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForMergerAndListingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">- Merger and listing expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForMergerAndListingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments For Merger And Listing Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForMergerAndListingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjustments for merger and listing expense.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfEffectOfChangesInForeignExchangeRatesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of effect of changes in foreign exchange rates [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfEffectOfChangesInForeignExchangeRatesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Sensitivity Changes in Exchange Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaximumReimbursementOfDevelopmentRelatedCost_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Maximum reimbursement of development related cost.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaximumReimbursementOfDevelopmentRelatedCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maximum Reimbursement Of Development Related Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaximumReimbursementOfDevelopmentRelatedCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maximum reimbursement of development related cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfFinanceCostExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Finance Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfFinanceCostExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of finance cost [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DescriptionOfAccountingPolicyOfNewStandardAndInterpretationsAdoptedExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description Of Accounting Policy Of New Standard And Interpretations Adopted Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DescriptionOfAccountingPolicyOfNewStandardAndInterpretationsAdoptedExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Description of accounting policy of new standard and interpretations adopted explanatory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DescriptionOfAccountingPolicyOfNewStandardAndInterpretationsAdoptedExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">New accounting standards, interpretations and amendments adopted by the Company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfSharesIncludingEarnoutOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Share and earnout options issued and outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfSharesIncludingEarnoutOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Dilutive Effect Of Shares Including Earnout Options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfSharesIncludingEarnoutOptions_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Dilutive effect of shares including earnout options.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaturityYearSixMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2030</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaturityYearSixMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maturity Year Six [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaturityYearSixMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Maturity year six.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalYearFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Fiscal Year Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalYearFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Fiscal Year Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OrdinarySharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Ordinary shares [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OrdinarySharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OrdinarySharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Ordinary Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_MaturityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maturity [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_MaturityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maturity [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DilutiveEffectOfShareOptionsOnNumberOfOrdinaryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share options issued and outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DilutiveEffectOfShareOptionsOnNumberOfOrdinaryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Dilutive effect of share options on weighted average number of ordinary shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted average number of ordinary shares used in calculating basic earnings per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted-average number of shares used to compute basic loss per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfOrdinarySharesToPipeInvestors_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Issuance of ordinary shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfOrdinarySharesToPipeInvestors_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of ordinary shares to PIPE investors ( in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfOrdinarySharesToPipeInvestors_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance of Ordinary Shares to Pipe Investors</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfOrdinarySharesToPipeInvestors_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of ordinary shares to pipe investors.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_GeographicalAreasDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Geographical areas [domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfContingentLiabilitiesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure Of Contingent Liabilities [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfContingentLiabilitiesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of contingent liabilities [table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForDecreaseIncreaseInLongTermPayables_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">- (De)/Increase in long-term payables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForDecreaseIncreaseInLongTermPayables_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments For Decrease Increase In Long Term Payables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForDecreaseIncreaseInLongTermPayables_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjustments for decrease increase in long term payables.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncreaseDecreaseInCashAndCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2009/role/netLabel">Net increase (decrease) in cash and cash equivalents after effect of exchange rate changes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncreaseDecreaseInCashAndCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (decrease) in cash and cash equivalents after effect of exchange rate changes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncreaseDecreaseInCashAndCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net cash and cash equivalents variation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncreaseDecreaseInCashAndCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Increase (decrease) in cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AmendedBlackrockWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amended Blackrock Warrant [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AmendedBlackrockWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amended Blackrock Warrant [Member].</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AmendedBlackrockWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amended Blackrock Warrant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Research And Development Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase (decrease) in research and development expense.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Increase (decrease) in research and development expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PercentageOfCapitalizedTransactionCostsForOldShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of transaction costs for Business Combination</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PercentageOfCapitalizedTransactionCostsForOldShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage of Capitalized Transaction Costs for Old Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PercentageOfCapitalizedTransactionCostsForOldShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of capitalized transaction costs for old shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncomeAndExpensesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income And Expenses [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncomeAndExpensesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income And Expenses [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncomeAndExpensesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Income and expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NoncurrentLiabilitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non-current liabilities</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_GrossCarryingAmountMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gross carrying amount [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_GrossCarryingAmountMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Acquisition cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentDecreaseInEuroMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">-5% EUR</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentDecreaseInEuroMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Five Percent Decrease In Euro [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentDecreaseInEuroMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Five percent decrease In Euro.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfWorkPackages_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of work packages</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfWorkPackages_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number Of Work Packages</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfWorkPackages_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of work packages.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfOtherEquityInstrumentsExercisedOrVestedInSharebasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of other equity instruments exercised restricted shares</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PotentialIssuanceOfEquityInConnectionWithExerciseOfOptionRightsOrOtherEquityLinkedInstruments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Potential issuance of equity in connection with exercise of option rights or other equity linked instruments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PotentialIssuanceOfEquityInConnectionWithExerciseOfOptionRightsOrOtherEquityLinkedInstruments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Potential Issuance Of Equity In Connection with Exercise of Option rights or Other Equity Linked Instruments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PotentialIssuanceOfEquityInConnectionWithExerciseOfOptionRightsOrOtherEquityLinkedInstruments_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Potential issuance of equity in connection with exercise of option rights or other equity linked instruments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AverageEffectiveTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Groups average expected tax rate</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AverageEffectiveTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Average effective tax rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AverageEffectiveTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total average effective tax rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageExercisePriceOfShareOptionsExercisedInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted Average Exercise Price, Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageExercisePriceOfShareOptionsExercisedInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted average exercise price of share options exercised in share-based payment arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaturityYearOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maturity Year One [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaturityYearOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Maturity year one.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaturityYearOneMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfSummaryOfSignificantAccountingPoliciesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Of Summary Of Significant Accounting Policies [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfSummaryOfSignificantAccountingPoliciesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of summary of significant accounting policies.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EuropeanBiotechAcquisitionCorpMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">EBAC</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EuropeanBiotechAcquisitionCorpMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">European Biotech Acquisition Corp [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EuropeanBiotechAcquisitionCorpMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">European Biotech Acquisition Corp [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LeasingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Leasing</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LeasingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Leasing [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LeasingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Leasing.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ComponentsOfOtherComprehensiveIncomeThatWillBeReclassifiedToProfitOrLossNetOfTaxAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Components of other comprehensive income that will be reclassified to profit or loss, net of tax [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ComponentsOfOtherComprehensiveIncomeThatWillBeReclassifiedToProfitOrLossNetOfTaxAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Items that may be reclassified subsequently to loss:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_EquityInterestsOfAcquirer_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity interests of acquirer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_EquityInterestsOfAcquirer_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">PIPE investments and conversion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfShareOptionsForfeitedInSharebasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Number of Options, Forfeited</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfShareOptionsForfeitedInSharebasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of share options forfeited in share-based payment arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashFlowsFromUsedInFinancingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Financing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashFlowsFromUsedInFinancingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash flows from (used in) financing activities [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfAccountingJudgementsAndEstimatesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Critical Accounting Estimates And Judgments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfAccountingJudgementsAndEstimatesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of accounting judgements and estimates [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PreferenceSharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preference Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PreferenceSharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preference shares [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfIntangibleAssetsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfIntangibleAssetsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of intangible assets [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForIncomeTaxExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfAccountingPolicyForIncomeTaxExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description of accounting policy for income tax [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_RangeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Range [domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_StatementOfChangesInEquityLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statement Of Changes In Equity [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_StatementOfChangesInEquityLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of changes in equity [line items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Property and equipment, net at end of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Property and equipment, net at beginning of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, plant and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total property, plant and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_Security12bTitle_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Title of 12(b) Security</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_Security12bTitle_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Title of 12(b) Security</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfShareOptionsGrantedInSharebasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Number of Options, Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfShareOptionsGrantedInSharebasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of shares, granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfShareOptionsGrantedInSharebasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of share options granted in share-based payment arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DefinedBenefitPlanGuaranteedInterestToBeCreditedToEmployeesSavings_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Guaranteed interest to be credited to employees savings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DefinedBenefitPlanGuaranteedInterestToBeCreditedToEmployeesSavings_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Defined Benefit Plan Guaranteed Interest To Be Credited To Employees Savings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DefinedBenefitPlanGuaranteedInterestToBeCreditedToEmployeesSavings_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Defined benefit plan guaranteed interest to be credited to employees savings.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RegisteredDirectOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Registered Direct Offering.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RegisteredDirectOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Registered Direct Offering</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RegisteredDirectOfferingMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Registered Direct Offering [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WomenMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Women</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WomenMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Women [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WomenMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Women.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutConsiderationSharePriceTargetOne_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share price target one</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutConsiderationSharePriceTargetOne_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnout consideration share price target one</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutConsiderationSharePriceTargetOne_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Earnout consideration share price target one.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WarrantsExercisableCommencingPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Exercisable Commencing Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WarrantsExercisableCommencingPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants exercisable commencing period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WarrantsExercisableCommencingPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrants exercisable commencing period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentInformationTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Information [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentInformationTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Information [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ReturnOnPlanAssetsExcludingInterestIncomeOrExpenseNetOfTaxDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">On plan assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ReturnOnPlanAssetsExcludingInterestIncomeOrExpenseNetOfTaxDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Return on plan assets excluding interest income or expense, net of tax, defined benefit plans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfPropertyPlantAndEquipmentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of detailed information about property, plant and equipment [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfContingentLiabilitiesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure Of Contingent Liabilities [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfContingentLiabilitiesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of contingent liabilities [line items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_FixturesAndFittingsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Laboratory Fixtures and Fittings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_FixturesAndFittingsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fixtures and fittings [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ImpairmentLossRecognisedInProfitOrLossIntangibleAssetsOtherThanGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impairment losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ImpairmentLossRecognisedInProfitOrLossIntangibleAssetsOtherThanGoodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Impairment loss recognised in profit or loss, intangible assets other than goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ImpairmentLossRecognisedInProfitOrLossIntangibleAssetsOtherThanGoodwill_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Impairment loss recognised in profit or loss, intangible assets other than goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PostemploymentBenefitExpenseDefinedContributionPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Employees' contributions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PostemploymentBenefitExpenseDefinedContributionPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Pension costs charges</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PostemploymentBenefitExpenseDefinedContributionPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Post-employment benefit expense, defined contribution plans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PostemploymentBenefitExpenseDefinedContributionPlans_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Employees' contributions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OtherCurrentAssetsOtherReceivableAndAccruedIncomeTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other Current Assets, Other Receivable and Accrued Income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OtherCurrentAssetsOtherReceivableAndAccruedIncomeTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Current Assets Other Receivable And Accrued Income [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OtherCurrentAssetsOtherReceivableAndAccruedIncomeTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Other current assets other receivable and accrued income text block.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfFinancialInstrumentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of detailed information about financial instruments [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfReconciliationOfLiabilitiesArisingFromFinancingActivitiesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of reconciliation of liabilities arising from financing activities [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfReconciliationOfLiabilitiesArisingFromFinancingActivitiesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Net Debt of Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_TradingSymbol_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Trading Symbol</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_TradingSymbol_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trading Symbol</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfBasisOfPreparationOfFinancialStatementsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basis of Preparation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfBasisOfPreparationOfFinancialStatementsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of basis of preparation of financial statements [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_InterestReceivedClassifiedAsInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest received, classified as investing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_InterestReceivedClassifiedAsInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_GainLossRecognisedInProfitOrLossForeignCurrencyRiskNetExposure_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net exposure in CHF</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_GainLossRecognisedInProfitOrLossForeignCurrencyRiskNetExposure_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gain Loss Recognised In Profit Or Loss Foreign Currency Risk Net Exposure</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_GainLossRecognisedInProfitOrLossForeignCurrencyRiskNetExposure_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Gain loss recognised in profit or loss foreign currency risk net exposure.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SwitzerlandPensionPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Switzerland pension plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SwitzerlandPensionPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Switzerland Pension Plan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SwitzerlandPensionPlanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Switzerland pension plan.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DepreciationRightofuseAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Depreciation charge for the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DepreciationRightofuseAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">- Depreciation of right-of-use assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DepreciationRightofuseAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Depreciation, right-of-use assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityExTransitionPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Ex Transition Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityExTransitionPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Ex Transition Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognisedLeasing_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deductible Temporary Differences For Which No Deferred Tax Asset Is Recognised Leasing</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognisedLeasing_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deductible temporary differences for which no deferred tax asset is recognised leasing.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognisedLeasing_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfAnalysisOfPresentValueOfDefinedBenefitObligationThatDistinguishesNatureCharacteristicsAndRisksExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Changes in Present Value of Defined Benefit Obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfAnalysisOfPresentValueOfDefinedBenefitObligationThatDistinguishesNatureCharacteristicsAndRisksExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of analysis of present value of defined benefit obligation that distinguishes nature, characteristics and risks [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DefinedBenefitPlansAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Defined benefit plans [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DefinedBenefitPlansAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Defined benefit plans [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PotentialDilutiveEffectNotIncludedInCalculationOfDilutedPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PotentialDilutiveEffectNotIncludedInCalculationOfDilutedPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Potential Dilutive Effect Not Included In Calculation Of Diluted Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PotentialDilutiveEffectNotIncludedInCalculationOfDilutedPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Potential dilutive effect not included in calculation of diluted per share.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionCostsRecordedInAccruedExpensesAndOtherPayables_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Transaction costs recorded in accrued expenses and other payables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionCostsRecordedInAccruedExpensesAndOtherPayables_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Transaction Costs Recorded In Accrued Expenses And Other Payables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionCostsRecordedInAccruedExpensesAndOtherPayables_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Transaction costs recorded in accrued expenses and other payables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SupplementalNonCashFinancingInformationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Supplemental Non Cash Financing Information [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SupplementalNonCashFinancingInformationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Supplemental non cash financing information.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SupplementalNonCashFinancingInformationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Supplemental non-cash financing information</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfClassesOfShareCapitalTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of classes of share capital [table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentIncreaseInHKDMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">+5% HKD</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentIncreaseInHKDMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Five Percent Increase In H K D [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentIncreaseInHKDMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Five Percent Increase In HKD.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_InterestIncomeDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_InterestIncomeDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest income, defined benefit plans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_InterestIncomeDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Interest income, defined benefit plans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TaxEffectOfUseOfUnrecognizedTaxLosses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effect of use of unrecognized tax losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TaxEffectOfUseOfUnrecognizedTaxLosses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tax Effect of Use of Unrecognized Tax Losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TaxEffectOfUseOfUnrecognizedTaxLosses_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tax effect of use of unrecognized tax losses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TaxEffectOfUseOfUnrecognizedTaxLosses_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Effect of use of unrecognized tax losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PlanAssetsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Plan assets [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PlanAssetsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Plan Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AccumulatedDepreciationAndAmortisationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated Depreciation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AccumulatedDepreciationAndAmortisationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated depreciation and amortisation [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseThroughSharesIssuedRelatedToUnderwrittenOfferingsEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (decrease) through shares issued related to underwritten offerings, equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseThroughSharesIssuedRelatedToUnderwrittenOfferingsEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase (decrease) through shares issued related to underwritten offerings, equity.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseThroughSharesIssuedRelatedToUnderwrittenOfferingsEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of ordinary shares related to underwritten offerings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PaymentOfFirstContractualNonRefundableCostContribution_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment of first contractual non refundable cost contribution</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PaymentOfFirstContractualNonRefundableCostContribution_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment Of First Contractual Non Refundable Cost Contribution</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PaymentOfFirstContractualNonRefundableCostContribution_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment of first contractual non refundable cost contribution.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_KeyManagementPersonnelCompensationShorttermEmployeeBenefits_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Salaries, cash compensation and other short-term benefits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_KeyManagementPersonnelCompensationShorttermEmployeeBenefits_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Key management personnel compensation, short-term employee benefits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AddressTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Address Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AddressTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Address Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentAnnualReport_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Annual Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentAnnualReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Annual Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_EquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_EquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity attributable to equity holders of the parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_BorrowingsByNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Borrowings by name [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfSharesIssuedInExchangeOfSharesInBusinessAcquisition_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of shares issued in exchange of shares in business acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfSharesIssuedInExchangeOfSharesInBusinessAcquisition_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Shares Issued in Exchange of Shares in Business Acquisition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfSharesIssuedInExchangeOfSharesInBusinessAcquisition_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of shares issued in exchange of shares in business acquisition.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ClassesOfIntangibleAssetsOtherThanGoodwillAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Classes of intangible assets other than goodwill [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ClassesOfIntangibleAssetsOtherThanGoodwillAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Classes of intangible assets other than goodwill [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfBusinessCombinationsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of detailed information about business combination [line items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfIntangibleAssetsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure Of Intangible Assets [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfIntangibleAssetsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of detailed information about intangible assets [table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ScheduleOfNetAssetsOfEbacTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Net assets of EBAC</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ScheduleOfNetAssetsOfEbacTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Net Assets Of EBAC Table Text Block</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ScheduleOfNetAssetsOfEbacTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of net assets of ebac table text block.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentAccountingStandard_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Accounting Standard</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentAccountingStandard_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Accounting Standard</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaturityYearTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maturity Year Two [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaturityYearTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Maturity year two.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaturityYearTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2026</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfCommonStockUponExerciseOfPublicWarrantsShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercise of public warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfCommonStockUponExerciseOfPublicWarrantsShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance Of Common Stock Upon Exercise Of Public Warrants Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfCommonStockUponExerciseOfPublicWarrantsShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of common stock upon exercise of public warrants shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">TOTAL ASSETS</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Assets at beginning of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Assets at end of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_EarningsPerShareLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings per share [line items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressesAddressTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Addresses, Address Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressesAddressTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Addresses, Address Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashAndCashEquivalentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and cash equivalents [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statistical Measurement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statistical Measurement [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TaxEffectOfTaxLosses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tax effect of tax losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TaxEffectOfTaxLosses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effect of unrecorded tax losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TaxEffectOfTaxLosses_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Effect of unrecorded tax losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TaxEffectOfTaxLosses_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Combined effect of unrecognized tax losses and intangible asset temporary differences</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_KeyManagementPersonnelCompensationPayrollExpensesRelatedToRestrictedStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payroll expenses related to restricted share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_KeyManagementPersonnelCompensationPayrollExpensesRelatedToRestrictedStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Key Management Personnel Compensation Payroll Expenses Related To Restricted Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_KeyManagementPersonnelCompensationPayrollExpensesRelatedToRestrictedStock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Key Management Personnel Compensation Payroll Expenses Related To Restricted Stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of other equity instruments outstanding in share-based payment arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Number of awards, Outstanding beginning balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NumberOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Number of awards, Outstanding ending balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PaymentsReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payments received.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PaymentsReceived_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Payments received during the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PaymentsReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payments received during the year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PaymentsReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments Received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_InterestReceivableRecordedInOtherCurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Receivable Recorded in Other Current Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_InterestReceivableRecordedInOtherCurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Interest receivable recorded in other current assets.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_InterestReceivableRecordedInOtherCurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest receivable recorded in other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ComponentsOfEquityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Components of equity [domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TypesOfSharebasedPaymentArrangementsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Types of share-based payment arrangements [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TypesOfSharebasedPaymentArrangementsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Types of share-based payment arrangements [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_OtherCurrencyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_OtherCurrencyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Currency [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AmountCapitalizedInDeductionOfSharePremiumEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amount Capitalized In Deduction Of Share Premium Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AmountCapitalizedInDeductionOfSharePremiumEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amount capitalized in deduction of share premium equity.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AmountCapitalizedInDeductionOfSharePremiumEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amount capitalized in deduction of share premium equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionsCostRelatedToBusinessCombinationAgreement_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Transaction costs related to the business combination</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionsCostRelatedToBusinessCombinationAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Transactions cost related to business combination agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionsCostRelatedToBusinessCombinationAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Transactions Cost Related to Business Combination Agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionsCostRelatedToBusinessCombinationAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Transaction costs related to BCA</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfFinancialInstrumentsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Financial Instruments / Risk Management</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfExpensesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Operating Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfExpensesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of expenses [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IcelandKronaCurrencyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Iceland Krona</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IcelandKronaCurrencyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Iceland Krona Currency [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IcelandKronaCurrencyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Iceland Krona currency.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ParValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Par value per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ParValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Par value per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialGainsLossesArisingFromExperienceAdjustmentsNetDefinedBenefitLiabilityAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Decrease (increase) in net defined benefit liability (asset) resulting from actuarial gains (losses) arising from experience adjustments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialGainsLossesArisingFromExperienceAdjustmentsNetDefinedBenefitLiabilityAsset_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Increase (decrease) in net defined benefit liability (asset) resulting from actuarial losses (gains) arising from experience adjustments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialGainsLossesArisingFromExperienceAdjustmentsNetDefinedBenefitLiabilityAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Actuarial losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdjustmentsForDepreciationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments for depreciation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdjustmentsForDepreciationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">- Depreciation of property and equipment and right-of-use assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageExercisePriceOfShareOptionsOutstandingInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Weighted Average Exercise Price, Outstanding beginning balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageExercisePriceOfShareOptionsOutstandingInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Weighted Average Exercise Price, Outstanding ending balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageExercisePriceOfShareOptionsOutstandingInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted average exercise price of share options outstanding in share-based payment arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfCashAndCashEquivalentsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and Cash Equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfCashAndCashEquivalentsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of cash and cash equivalents [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RightOfUseAssetsForeignCurrencyRevaluation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">FX revaluation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RightOfUseAssetsForeignCurrencyRevaluation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Right Of Use Assets Foreign Currency Revaluation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RightOfUseAssetsForeignCurrencyRevaluation_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Right of use assets foreign currency revaluation.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashTransferred_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash transferred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashTransferred_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash transferred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementProcessesForAssessingIdentifyingAndManagingThreatsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Processes for Assessing, Identifying, and Managing Threats [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RestrictedStockAwardsSubjectToRepurchase_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">RSA's subject to repurchase</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RestrictedStockAwardsSubjectToRepurchase_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Stock Awards Subject To Repurchase</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RestrictedStockAwardsSubjectToRepurchase_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Restricted stock awards subject to repurchase.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfQuantitativeInformationAboutRightofuseAssetsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of quantitative information about right-of-use assets [table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PrepaidClinicalAndTechnicalDevelopmentExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid clinical and technical development expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PrepaidClinicalAndTechnicalDevelopmentExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Clinical And Technical Development Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PrepaidClinicalAndTechnicalDevelopmentExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Prepaid clinical and technical development expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfRestrictedStockUnitsSubjectToFutureVesting_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted stock units subject to future vesting</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfRestrictedStockUnitsSubjectToFutureVesting_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Dilutive Effect of Restricted Stock Units Subject to Future Vesting</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfRestrictedStockUnitsSubjectToFutureVesting_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Dilutive effect of restricted stock units subject to future vesting.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DepreciationExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Depreciation Expense [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DepreciationExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Depreciation expense member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DepreciationExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Depreciation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdjustedWeightedAverageShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted average number of ordinary shares used in calculating diluted earnings per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AdjustedWeightedAverageShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted-average number of shares used to compute diluted loss per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfIndirectMeasurementOfFairValueOfGoodsOrServicesReceivedShareOptionsGrantedDuringPeriodExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of indirect measurement of fair value of goods or services received, share options granted during period [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfIndirectMeasurementOfFairValueOfGoodsOrServicesReceivedShareOptionsGrantedDuringPeriodExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Weighted-Average Assumptions for Black-Scholes Option-Pricing Model Used</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfSensitivityAnalysisForActuarialAssumptionsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Quantitative Sensitivity Analysis for Significant Assumptions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfSensitivityAnalysisForActuarialAssumptionsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of sensitivity analysis for actuarial assumptions [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NoncurrentAssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non-current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NoncurrentAssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non-current assets [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfCurrentIncomeTaxExpenseAndDeferredTaxExpenseExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Total Tax (Expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfCurrentIncomeTaxExpenseAndDeferredTaxExpenseExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Of Current Income Tax Expense And Deferred Tax Expense Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfCurrentIncomeTaxExpenseAndDeferredTaxExpenseExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of current income tax (expense) and deferred tax (expense) explanatory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfFinanceIncomeExpenseExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Finance Result</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfFinanceIncomeExpenseExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of finance income (cost) [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaturityYearThreeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maturity Year Three [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaturityYearThreeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Maturity year three.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaturityYearThreeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2027</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DilutedEarningsLossPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Diluted earnings (loss) per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DilutedEarningsLossPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total diluted earnings (loss) per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DilutedEarningsLossPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Diluted net loss per share for the period, in CHF</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DilutedEarningsLossPerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Diluted, loss attributable to equity holders</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of detailed information about borrowings [line items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ShareExchangeRatio_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exchange Ratio</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ShareExchangeRatio_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share Exchange Ratio</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ShareExchangeRatio_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Share exchange ratio.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityRegistrantName_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Registrant Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityRegistrantName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Registrant Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfDefinedBenefitPlansAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of defined benefit plans [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityVoluntaryFilers_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Voluntary Filers</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityVoluntaryFilers_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Voluntary Filers</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognisedPension_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Pension</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognisedPension_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deductible Temporary Differences For Which No Deferred Tax Asset Is Recognised Pension</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognisedPension_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deductible temporary differences for which no deferred tax asset is recognised, pension.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_StatementOfChangesInEquityTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statement Of Changes In Equity [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_StatementOfChangesInEquityTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of changes in equity placeholder - this item MUST be used as a starting point for the statement of changes in equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForIncreaseDecreaseInCashFlowsFromUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments For Increase Decrease In Cash Flows From Used In Operating Activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForIncreaseDecreaseInCashFlowsFromUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjustments for increase (decrease) in cash flows from used in operating activities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForIncreaseDecreaseInCashFlowsFromUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Increase in net cash outflow from operating activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RemainingNumber0FWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Remaining number of warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RemainingNumber0FWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Remaining Number 0f warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_RemainingNumber0FWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Remaining Number 0f warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TriggeredMilestonePayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Milestone payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TriggeredMilestonePayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Triggered Milestone Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TriggeredMilestonePayment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Triggered milestone payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ContributionsToPlanByPlanParticipantsNetDefinedBenefitLiabilityAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contributions paid by participants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ContributionsToPlanByPlanParticipantsNetDefinedBenefitLiabilityAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Decrease (increase) in net defined benefit liability (asset) resulting from contributions to plan by plan participants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ContributionsToPlanByPlanParticipantsNetDefinedBenefitLiabilityAsset_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Increase (decrease) in net defined benefit liability (asset) resulting from contributions to plan by plan participants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="cyd_CybersecurityRiskManagementPositionsOrCommitteesResponsibleFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cybersecurity Risk Management Positions or Committees Responsible [Flag]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AccruedIncomeIncludingContractAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AccruedIncomeIncludingContractAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Balance as of January 1,</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AccruedIncomeIncludingContractAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Balance as of December 31,</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AccruedIncomeIncludingContractAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued income including contract assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AccruedIncomeIncludingContractAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total accrued income including contract assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ValuationTechniquesUsedInFairValueMeasurementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Valuation techniques used in fair value measurement [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfShareOptionsExercisedAndRestrictedShareUnitsReleased_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock options exercised and RSUs released (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfShareOptionsExercisedAndRestrictedShareUnitsReleased_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Share Options Exercised and Restricted Share Units Released</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfShareOptionsExercisedAndRestrictedShareUnitsReleased_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of share options exercised and restricted share units released.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TreasuryShares_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Treasury shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TreasuryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Treasury shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TreasuryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Treasury shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_InterestExpenseDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest cost on benefit obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_InterestExpenseDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest expense, defined benefit plans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_InterestExpenseDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Interest cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_InterestExpenseDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Interest cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_InterestExpenseDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Interest cost on benefit obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfNetDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Net Debt of Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfNetDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Of Net Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfNetDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of net debt.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_StatementOfComprehensiveIncomeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of comprehensive income [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PresentValueOfDefinedBenefitObligationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Present value of defined benefit obligation [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PresentValueOfDefinedBenefitObligationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Present Value of Defined Benefit Obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Common Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Common Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_SharePremiumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share premium</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_SharePremiumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share premium [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_Equity_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_Equity_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_Equity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_Equity_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialAssumptionOfMortalityRatesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Actuarial assumption of mortality rates [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialAssumptionOfMortalityRatesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Mortality Assumptions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfReclassificationOfFinancialInstrumentsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Carrying Amounts of Financial Assets and Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfReclassificationOfFinancialInstrumentsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of reclassification of financial instruments [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NetDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net debt as of December 31, 2020</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NetDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NetDebt_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedPeriodStartLabel">Net debt beginning balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NetDebt_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedPeriodEndLabel">Net debt ending balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NetDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Book value of long term financial debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialAssumptionOfExpectedRatesOfSalaryIncreasesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Actuarial assumption of expected rates of salary increases [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialAssumptionOfExpectedRatesOfSalaryIncreasesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Future Salary Increase</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PaymentForShortTermFinancialAssetsClassifiedAsInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Payment for short-term financial assets, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PaymentForShortTermFinancialAssetsClassifiedAsInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment For Short Term Financial Assets Classified As Investing Activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PaymentForShortTermFinancialAssetsClassifiedAsInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment for short term financial assets classified as investing activities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ClassesOfPropertyPlantAndEquipmentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Classes of property, plant and equipment [domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FirstMilestonePayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">First milestone payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FirstMilestonePayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">First Milestone Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FirstMilestonePayment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">First milestone payment.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PIPEInvestorsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">PIPE investors.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PIPEInvestorsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">PIPE Investors [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageExercisePriceOfOtherEquityInstrumentsExercisedOrVestedInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average grant date fair value, RSUs vested/setttled</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageExercisePriceOfOtherEquityInstrumentsExercisedOrVestedInSharebasedPaymentArrangement2019_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted average exercise price of other equity instruments exercised or vested in share-based payment arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExpectedTermShareOptionsGranted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expected term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExpectedTermShareOptionsGranted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Expected Term Share Options Granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExpectedTermShareOptionsGranted_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Expected term, share options granted.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExpectedTermShareOptionsGranted_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Range of expected terms</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ServiceCostDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Service cost, defined benefit plans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ServiceCostDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Service cost, defined benefit plans.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ServiceCostDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Service cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ServiceCostDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Service cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustedWeightedAverageSharesRestated_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted-average number of shares used to compute loss per share diluted (as restated)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustedWeightedAverageSharesRestated_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjusted Weighted Average Shares Restated</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustedWeightedAverageSharesRestated_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjusted weighted average shares restated.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionCostsRelatedToTheValueOfBusinessCombination_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Transaction costs related to the business combination</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionCostsRelatedToTheValueOfBusinessCombination_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Transaction costs related to the business combination</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionCostsRelatedToTheValueOfBusinessCombination_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Transaction Costs Related to The Value of Business Combination</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionCostsRelatedToTheValueOfBusinessCombination_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Transaction costs related to the value of business combination.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">General and administrative expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">General and administrative expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">General and Administrative Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">General and administrative expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ExpenseFromSharebasedPaymentTransactionsInWhichGoodsOrServicesReceivedDidNotQualifyForRecognitionAsAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total expense from share-based payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ExpenseFromSharebasedPaymentTransactionsInWhichGoodsOrServicesReceivedDidNotQualifyForRecognitionAsAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expenses for share based payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ExpenseFromSharebasedPaymentTransactionsInWhichGoodsOrServicesReceivedDidNotQualifyForRecognitionAsAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Expense from share-based payment transactions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TaxEffectOfExpenseNotDeductibleInDeterminingTaxableProfitTaxLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effect of unrecorded tax losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TaxEffectOfExpenseNotDeductibleInDeterminingTaxableProfitTaxLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tax effect of expense not deductible in determining taxable profit (tax loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TaxEffectOfExpenseNotDeductibleInDeterminingTaxableProfitTaxLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Effect of non deductible expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_TaxEffectOfExpenseNotDeductibleInDeterminingTaxableProfitTaxLoss_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Effect of non deductible expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PlanAssetsAtFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Fair value of plan assets at January 1,</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PlanAssetsAtFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair value of plan assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PlanAssetsAtFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Plan assets, at fair value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PlanAssetsAtFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total plan assets, at fair value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PlanAssetsAtFairValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Fair value of plan assets at December 31,</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BusinessCombinationsMergerAndListingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Business Combinations Merger and Listing Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BusinessCombinationsMergerAndListingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Incurred expense amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BusinessCombinationsMergerAndListingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Merger and listing expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BusinessCombinationsMergerAndListingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combinations Merger and Listing Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BusinessCombinationsMergerAndListingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Business combinations merger and listing expense.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_RetainedEarnings_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retained earnings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_RetainedEarnings_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total retained earnings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_RetainedEarnings_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_AnalysisOfIncomeAndExpenseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Analysis of income and expense [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfAttributionOfExpensesByNatureToTheirFunctionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure Of Attribution Of Expenses By Nature To Their Function [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfAttributionOfExpensesByNatureToTheirFunctionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of attribution of expenses by nature to their function [line items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_EquityAndLiabilitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">EQUITY AND LIABILITIES</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_EquityAndLiabilitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity and liabilities [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BenefitsPaidFromPlanAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Benefits paid from plan assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BenefitsPaidFromPlanAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Benefits Paid From Plan Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BenefitsPaidFromPlanAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Benefits paid from plan assets.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BenefitsPaidFromPlanAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Benefits paid from plan assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognised_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deductible temporary differences for which no deferred tax asset is recognised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfDetailedInFormationAboutWarrantLiabilityExplanatoryTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Movement of Warrant Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfDetailedInFormationAboutWarrantLiabilityExplanatoryTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Of Detailed In formation About Warrant Liability Explanatory Table [Text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfDetailedInFormationAboutWarrantLiabilityExplanatoryTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of detailed in formation about warrant liability explanatory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfPropertyPlantAndEquipmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disclosure Of Property Plant And Equipment [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfPropertyPlantAndEquipmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of detailed information about property, plant and equipment [table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExercisableShareExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Exercisable shares expiration period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExercisableShareExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Exercisable Share Expiration Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExercisableShareExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Exercisable share expiration period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInPotentialDefinedBenefitObligationDueToReasonablyPossibleDecreaseInActuarialAssumption_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase (decrease) in potential defined benefit obligation due to reasonably possible decrease in actuarial assumption.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInPotentialDefinedBenefitObligationDueToReasonablyPossibleDecreaseInActuarialAssumption_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (decrease) in potential defined benefit obligation due to reasonably possible decrease in actuarial assumption</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInPotentialDefinedBenefitObligationDueToReasonablyPossibleDecreaseInActuarialAssumption_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Potential defined benefit obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CityAreaCode_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">City Area Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CityAreaCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">City Area Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInOperatingExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Increase (decrease) in operating expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInOperatingExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Operating Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IncreaseDecreaseInOperatingExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase (decrease) in operating expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfTradingDays_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of trading days.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfTradingDays_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Trading days</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfTradingDays_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of trading days</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForDecreaseIncreaseInAccruedExpensesAndOtherPayables_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">- (De)/Increase in accrued expenses and other payables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForDecreaseIncreaseInAccruedExpensesAndOtherPayables_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments For Decrease Increase In Accrued Expenses And Other Payables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForDecreaseIncreaseInAccruedExpensesAndOtherPayables_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjustments for decrease increase in accrued expenses and other payables.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AuditorName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Auditor Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfRestrictedStockSubjectToRepurchase_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Dilutive Effect Of Restricted Stock Subject To Repurchase</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfRestrictedStockSubjectToRepurchase_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Dilutive effect of restricted stock subject to repurchase.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectOfRestrictedStockSubjectToRepurchase_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted shares subject to repurchase</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectEarnoutOptionsOutstandingAndExercisable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Dilutive Effect Earnout Options Outstanding And Exercisable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectEarnoutOptionsOutstandingAndExercisable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Dilutive effect earnout options outstanding and exercisable.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectEarnoutOptionsOutstandingAndExercisable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Earnouts options outstanding and exercisable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DilutiveEffectEarnoutOptionsOutstandingAndExercisable_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Earnout options exercisable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PurchaseOfPropertyPlantAndEquipmentClassifiedAsInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Purchase of property, plant and equipment, classified as investing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PurchaseOfPropertyPlantAndEquipmentClassifiedAsInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Purchase of property, plant and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PurchaseOfPropertyPlantAndEquipmentClassifiedAsInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Payment for purchase of property and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_KreosCapitalVIIUKLimitedMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Kreos Capital VII (UK) Limited [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_KreosCapitalVIIUKLimitedMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Kreos Capital VII (UK) Limited [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_KreosCapitalVIIUKLimitedMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Kreos Capital VII (UK) Limited</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IcelandAndUnitedStatesFacilitiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Iceland and U.S.Facilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IcelandAndUnitedStatesFacilitiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Iceland and United States Facilities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IcelandAndUnitedStatesFacilitiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Iceland and United States facilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and development expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and development expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Research and Development Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Research and development expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NoncurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total non-current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NoncurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non-current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_StatementOfCashFlowsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of cash flows [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CommitmentsForExternalResearchProjectsWithinOneYear_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Within one year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CommitmentsForExternalResearchProjectsWithinOneYear_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments For External Research Projects Within One Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CommitmentsForExternalResearchProjectsWithinOneYear_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Commitments for external research projects within one year.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrentPrepaymentsAndCurrentAccruedIncomeIncludingCurrentContractAssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current prepayments and current accrued income including current contract assets [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ActuarialLossOnPostEmploymentBenefitObligations_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Actuarial loss on post employment benefit obligations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ActuarialLossOnPostEmploymentBenefitObligations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Actuarial Loss On Post Employment Benefit Obligations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ActuarialLossOnPostEmploymentBenefitObligations_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Actuarial loss on post employment benefit obligations.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ActuarialLossOnPostEmploymentBenefitObligations_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Actuarial loss on post employment benefit obligations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OfficeFurnitureAndEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Office Furniture and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OfficeFurnitureAndEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Office Furniture And Equipment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OfficeFurnitureAndEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Office furniture and equipment.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CommitmentsForExternalResearchProjectsBetweenOneAndFiveYears_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Between one and five years</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CommitmentsForExternalResearchProjectsBetweenOneAndFiveYears_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments For External Research Projects Between One And Five Years</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_CommitmentsForExternalResearchProjectsBetweenOneAndFiveYears_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Commitments for external research projects between one and five years.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaturityYearFiveMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maturity Year Five [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaturityYearFiveMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Maturity Year Five.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_MaturityYearFiveMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2029</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionsCostsRelatedToFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Transaction costs related to financing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionsCostsRelatedToFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Transactions Costs Related to Financing Activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_TransactionsCostsRelatedToFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Transactions costs related to financing activities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_KeyManagementPersonnelCompensationSharebasedPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_KeyManagementPersonnelCompensationSharebasedPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Key management personnel compensation, share-based payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForIncreaseDecreaseInCashFlowsFromUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments For Increase Decrease In Cash Flows From Used In Financing Activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForIncreaseDecreaseInCashFlowsFromUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjustments for increase (decrease) in cash flows from used in financing activities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForIncreaseDecreaseInCashFlowsFromUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Decrease in net cash outflow from financing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ClassesOfAssetsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Classes of assets [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ForeignCurrencyRevaluation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">FX revaluation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ForeignCurrencyRevaluation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Foreign Currency Revaluation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ForeignCurrencyRevaluation_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">FX revaluation.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExpenseFromSharebasedPaymentTransactionsAttributableToModificationRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Expense from sharebased payment transactions attributable to modification recognized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExpenseFromSharebasedPaymentTransactionsAttributableToModificationRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Expense From Sharebased Payment Transactions Attributable To Modification Recognized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExpenseFromSharebasedPaymentTransactionsAttributableToModificationRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Expense From Sharebased Payment Transactions Attributable To Modification Recognized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConversionOfOrdinaryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion of ordinary shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConversionOfOrdinaryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Conversion of ordinary shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ConversionOfOrdinaryShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Conversion of oridinary shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ProceedsFromExerciseOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from exercise of warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ProceedsFromExerciseOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from exercises of warrants, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NetDeferredTaxAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net deferred tax assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NetDeferredTaxAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred tax asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_NonadjustingEventsAfterReportingPeriodDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non-adjusting events after reporting period [domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ForfeitedSharesExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Forfeited shares expiration period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ForfeitedSharesExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Forfeited Shares Expiration Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ForfeitedSharesExpirationPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Forfeited shares expiration period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashFlowsFromUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CashFlowsFromUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash flows from (used in) operating activities [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentDecreaseInUSDMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">-5% USD</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentDecreaseInUSDMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Five Percent Decrease In U S D [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_FivePercentDecreaseInUSDMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Five Percent Decrease In USD.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfExpectedVolatilityShareOptionsGranted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Range of expected volatilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfExpectedVolatilityShareOptionsGranted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Expected volatility, share options granted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DescriptionOfExpectedVolatilityShareOptionsGranted_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Expected volatility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PayrollAndRelatedPersonnelExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payroll And Related Personnel Expenses [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PayrollAndRelatedPersonnelExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payroll and related personnel expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_PayrollAndRelatedPersonnelExpensesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payroll and Related Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressCountry_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, Country</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressCountry_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Country</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_LeaseholdImprovementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Leasehold improvements [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_LeaseholdImprovementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Leasehold Improvement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForDecreaseIncreaseInOtherOperatingAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments For Decrease Increase In Other Operating Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForDecreaseIncreaseInOtherOperatingAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjustments for decrease increase in other operating assets.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForDecreaseIncreaseInOtherOperatingAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">- De/(Increase) in other operating assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_EarningsPerShareExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Loss Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_EarningsPerShareExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings per share [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DescriptionOfAccountingPolicyOfCurrentVersusNoncurrentClassificationExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current vs. non-current classification</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DescriptionOfAccountingPolicyOfCurrentVersusNoncurrentClassificationExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description Of Accounting Policy Of Current Versus Noncurrent Classification Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DescriptionOfAccountingPolicyOfCurrentVersusNoncurrentClassificationExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Description of accounting policy of current versus noncurrent classification explanatory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SharesOutstandingAndIssuedPriorToTheBusinessCombination_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of shares outstanding and issued prior to the business combination</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SharesOutstandingAndIssuedPriorToTheBusinessCombination_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shares Outstanding And Issued Prior To The Business Combination</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_SharesOutstandingAndIssuedPriorToTheBusinessCombination_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Shares outstanding and issued prior to the business combination.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfDetailedInformationAboutIntangibleAssetsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summarizes the Movement of Intangibles Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfDetailedInformationAboutIntangibleAssetsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of detailed information about intangible assets [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ScheduleOfTradePayables_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Trade Payables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ScheduleOfTradePayables_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Trade Payables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ScheduleOfTradePayables_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of trade payables.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialGainsLossesArisingFromExperienceAdjustmentsNetOfTaxDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialGainsLossesArisingFromExperienceAdjustmentsNetOfTaxDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Actuarial gains (losses) arising from experience adjustments, net of tax, defined benefit plans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialGainsLossesArisingFromExperienceAdjustmentsNetOfTaxDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">On obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialGainsLossesArisingFromExperienceAdjustmentsNetOfTaxDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Actuarial gains / (losses)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AuditorLocation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Auditor Location</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialAssumptionsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Actuarial assumptions [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_ActuarialAssumptionsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Actuarial assumptions [axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OtherNoncurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other non-current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_OtherNoncurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other non-current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ClassBOrdinarySharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Class B Ordinary Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ClassBOrdinarySharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class B Ordinary Shares [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ClassBOrdinarySharesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Class B Ordinary Shares [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutConsiderationSharePriceTargetTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Earnout consideration share price target two.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutConsiderationSharePriceTargetTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share price target two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_EarnoutConsiderationSharePriceTargetTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnout consideration share price target Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExerciseOfPublicAndPrivateWarrants_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Exercise of public and private warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExerciseOfPublicAndPrivateWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercise of public and private warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExerciseOfPublicAndPrivateWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Exercise of Public and Private Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ExerciseOfPublicAndPrivateWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Exercise of public and private warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_SubclassificationsOfAssetsLiabilitiesAndEquitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subclassifications of assets, liabilities and equities [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_RevenueFromGovernmentGrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income from government grants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_RevenueFromGovernmentGrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Government grant income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_RevenueFromGovernmentGrants_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Grant income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_MajorComponentsOfTaxExpenseIncomeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Major components of tax expense (income) [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BlackrockWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Blackrock Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BlackrockWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Blackrock Warrant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BlackrockWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Blackrock Warrant [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_BlackrockWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Blackrock warrant.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of transactions between related parties [table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LoanTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loan Two [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LoanTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Loan two.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LoanTwoMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loan 2</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityInteractiveDataCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Interactive Data Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityInteractiveDataCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Interactive Data Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_UpfrontPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Upfront payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_UpfrontPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Upfront Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_UpfrontPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Upfront payment.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfQuantitativeInformationAboutLeaseLiabilitiesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Lease Obligations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfQuantitativeInformationAboutLeaseLiabilitiesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure Of Quantitative Information About Lease Liabilities Explanatory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_DisclosureOfQuantitativeInformationAboutLeaseLiabilitiesExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Disclosure of quantitative information about lease liabilities explanatory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncreaseDecreaseThroughConversionOfConvertibleInstruments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (decrease) through conversion of convertible instruments, equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IncreaseDecreaseThroughConversionOfConvertibleInstruments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion of Legacy Oculis ordinary shares and treasury shares into Oculis ordinary shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfWarrants_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Issuance of warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issuance of Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_IssuanceOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Issuance of warrants.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NetCashFlowsFromFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Net cash flows from financing activities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NetCashFlowsFromFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Cash Flows From Financing Activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NetCashFlowsFromFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payments for the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OfferingPriceOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Offering price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OfferingPriceOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Offering Price Of Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_OfferingPriceOfShares_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Offering price of shares.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_FinancialAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Financial assets at beginning of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_FinancialAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Financial assets at end of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_FinancialAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Financial assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_FinancialAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Financial assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PostemploymentBenefitExpenseDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net benefit income / (expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PostemploymentBenefitExpenseDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Post-employment benefit expense in profit or loss, defined benefit plans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PostemploymentBenefitExpenseDefinedBenefitPlans_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel">Net benefit expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfQuantitativeInformationAboutRightofuseAssetsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Right-of-use Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisclosureOfQuantitativeInformationAboutRightofuseAssetsExplanatory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disclosure of quantitative information about right-of-use assets [text block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisposalsPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Disposals</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisposalsPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disposals, property, plant and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_DisposalsPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Disposals, property, plant and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WarrantsVestedAndExercisable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Vested And Exercisable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WarrantsVestedAndExercisable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants vested and exercisable.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_WarrantsVestedAndExercisable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrant vested and exercisable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_PresentationOfLeasesForLesseeAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Presentation of leases for lessee [abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForIncreaseDecreaseInCashFlowsFromUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Decrease in net cash outflow from investing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForIncreaseDecreaseInCashFlowsFromUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments For Increase Decrease In Cash Flows From Used In Investing Activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_AdjustmentsForIncreaseDecreaseInCashFlowsFromUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Adjustments for increase decrease in cash flows from used in investing activities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfManagedAndOperatedSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of managed and operated segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfManagedAndOperatedSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number Of Managed And Operated Segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfManagedAndOperatedSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of managed and operated segments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrentWarrantLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Warrant liabilities, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrentWarrantLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Warrant liabilities, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrentWarrantLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrant liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_CurrentWarrantLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current warrant liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LegacyOculisMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Legacy Oculis [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LegacyOculisMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Legacy oculis.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_LegacyOculisMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Legacy Oculis [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IssuedCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Issued capital [member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IssuedCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_IssuedCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Share capital [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ScheduleOfOrdinarySharesIssuedAndOutstandingTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Ordinary Shares Issued and Outstanding and Ownership Interests After Business Combination</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ScheduleOfOrdinarySharesIssuedAndOutstandingTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Ordinary Shares Issued And Outstanding Table Text Block</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_ScheduleOfOrdinarySharesIssuedAndOutstandingTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule Of Ordinary Shares Issued And Outstanding Table Text Block</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NonRefundableContractCostContribution_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non-refundable contract cost contribution</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NonRefundableContractCostContribution_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Non-refundable Contract Cost Contribution</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NonRefundableContractCostContribution_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Non-refundable contract cost contribution.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageRemainingContractualLifeOfOutstandingShareOptions2019_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted average remaining contractual life of options outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ifrs-full_WeightedAverageRemainingContractualLifeOfOutstandingShareOptions2019_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted average remaining contractual life of outstanding share options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfSharesCancelled_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of shares cancelled</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfSharesCancelled_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Shares Cancelled</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ocs_NumberOfSharesCancelled_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of shares cancelled.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_LocalPhoneNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Local Phone Number</link:label>
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  <xsd:element id="ocs_NumberOfGroupEntitiesForConsolidation" name="NumberOfGroupEntitiesForConsolidation" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_AggregateMaximumOfferingPrice" name="AggregateMaximumOfferingPrice" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_IncreaseDecreaseInAccumulatedTaxLosses" name="IncreaseDecreaseInAccumulatedTaxLosses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
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  <xsd:element id="ocs_MilestonePaymentsDueUponTrial" name="MilestonePaymentsDueUponTrial" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_WarrantsExercisableCommencingPeriod" name="WarrantsExercisableCommencingPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_RestrictedStockAwardsMember" name="RestrictedStockAwardsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_SubscriptionPricePerShare" name="SubscriptionPricePerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DisclosureOfWarrantLiabilitiesAbstract" name="DisclosureOfWarrantLiabilitiesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_IncomeAndExpensesLineItems" name="IncomeAndExpensesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_ActuarialAssumptionOfDemographicAssumptions" name="ActuarialAssumptionOfDemographicAssumptions" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_BenefitsPaidFromPlanAssets" name="BenefitsPaidFromPlanAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_PercentageOfCommissionOnGrossProceeds" name="PercentageOfCommissionOnGrossProceeds" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_NumberOfShareOptionsExercisedAndRestrictedShareUnitsVestedOrReleased" name="NumberOfShareOptionsExercisedAndRestrictedShareUnitsVestedOrReleased" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DilutiveEffectEarnoutOptions" name="DilutiveEffectEarnoutOptions" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ExpenseFromSharebasedPaymentTransactionsAttributableToModificationRecognized" name="ExpenseFromSharebasedPaymentTransactionsAttributableToModificationRecognized" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_LoanThreeMember" name="LoanThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_PresentationOfInterestInTheStatementOfCashFlowsPolicyPolicyTextBlock" name="PresentationOfInterestInTheStatementOfCashFlowsPolicyPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DisclosureOfSummaryOfRestrictedStockUnitActivityUnderEmployeeStockOptionPlanExplanatory" name="DisclosureOfSummaryOfRestrictedStockUnitActivityUnderEmployeeStockOptionPlanExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_PotentialIssuanceOfEquityThroughExerciseOfWarrants" name="PotentialIssuanceOfEquityThroughExerciseOfWarrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_DisclosureOfShareCapitalSharePremiumAndTreasurySharesAbstract" name="DisclosureOfShareCapitalSharePremiumAndTreasurySharesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_DisclosureOfNetDebt" name="DisclosureOfNetDebt" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DilutiveEffectOfEarnoutShares" name="DilutiveEffectOfEarnoutShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DisclosureOfDeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognisedExplanatory" name="DisclosureOfDeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognisedExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ConversionOfLegacyOculisLongTermFinancialDebtIntoOculisOrdinarySharesValue" name="ConversionOfLegacyOculisLongTermFinancialDebtIntoOculisOrdinarySharesValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_NumberOfOutstandingWarrantsShare" name="NumberOfOutstandingWarrantsShare" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DescriptionOfAccountingPolicyOfCashAndCashEquivalentsAndShortTermFinancialAssetsExplanatoryTextBlock" name="DescriptionOfAccountingPolicyOfCashAndCashEquivalentsAndShortTermFinancialAssetsExplanatoryTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_RightOfUseAssetsForeignCurrencyRevaluation" name="RightOfUseAssetsForeignCurrencyRevaluation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_MaturityYearTwoMember" name="MaturityYearTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_DisclosureOfBasisOfPreparationAndChangesToGroupAccountingPoliciesLineItems" name="DisclosureOfBasisOfPreparationAndChangesToGroupAccountingPoliciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_DisclosureOfIncomeAndExpensesTextBlock" name="DisclosureOfIncomeAndExpensesTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_EuropeanBiotechAcquisitionCorpMember" name="EuropeanBiotechAcquisitionCorpMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_ScheduleOfOrdinarySharesIssuedAndOutstandingTableTextBlock" name="ScheduleOfOrdinarySharesIssuedAndOutstandingTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_MaturityYearFiveMember" name="MaturityYearFiveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_ExpectedTermShareOptionsGranted" name="ExpectedTermShareOptionsGranted" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_StockAppreciationRightsMember" name="StockAppreciationRightsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_DisclosureOfWarrantLiabilitiesExplanatory" name="DisclosureOfWarrantLiabilitiesExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_PercentageOfProjectManagementFee" name="PercentageOfProjectManagementFee" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ScheduleOfMergerAndListingTableTextBlock" name="ScheduleOfMergerAndListingTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_WeightedAverageExercisePriceOfStockAppreciationRightsGrantedInSharebasedPaymentArrangement2019" name="WeightedAverageExercisePriceOfStockAppreciationRightsGrantedInSharebasedPaymentArrangement2019" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_OfficeEquipmentHardwareMember" name="OfficeEquipmentHardwareMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_FairValueAdjustmentOnWarrantLiabilities" name="FairValueAdjustmentOnWarrantLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_GrantedStockAppreciationRightsExpirationPeriod" name="GrantedStockAppreciationRightsExpirationPeriod" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_CashAndCashEquivalentsAndShortTermFinancialAssetsLineItems" name="CashAndCashEquivalentsAndShortTermFinancialAssetsLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_AdjustmentsForFairValueAdjustmentOnWarrantLiabilities" name="AdjustmentsForFairValueAdjustmentOnWarrantLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_MaximumBorrowingCapacity" name="MaximumBorrowingCapacity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_BlackrockWarrantMember" name="BlackrockWarrantMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_RemainingNumber0FWarrants" name="RemainingNumber0FWarrants" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DilutiveEffectOfUnvestedEarnoutShares" name="DilutiveEffectOfUnvestedEarnoutShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_IncreaseDecreaseInProfitLoss" name="IncreaseDecreaseInProfitLoss" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_NumberOfReportingSegments" name="NumberOfReportingSegments" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_TwoThousandTwentyThreePlanMember" name="TwoThousandTwentyThreePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_DisclosureOfSummaryOfSignificantAccountingPoliciesAbstract" name="DisclosureOfSummaryOfSignificantAccountingPoliciesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_FixedTermBankDepositsMaturityTerm" name="FixedTermBankDepositsMaturityTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ProjectManagementFee" name="ProjectManagementFee" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_AdditionOfLease" name="AdditionOfLease" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_IntangibleAssetsAcquisitionRecordedInAccruedExpenses" name="IntangibleAssetsAcquisitionRecordedInAccruedExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_NumberOfTradingDays" name="NumberOfTradingDays" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_RedemptionOptionAmountEquivalentToInvestorsInvestmentAccruedDividendAndCompoundInterestRate" name="RedemptionOptionAmountEquivalentToInvestorsInvestmentAccruedDividendAndCompoundInterestRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_IncreaseDecreaseInPotentialDefinedBenefitObligationDueToReasonablyPossibleDecreaseInActuarialAssumption" name="IncreaseDecreaseInPotentialDefinedBenefitObligationDueToReasonablyPossibleDecreaseInActuarialAssumption" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_ApplicableRateForTwentyTwentySevenMember" name="ApplicableRateForTwentyTwentySevenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_EligibleCosts" name="EligibleCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_IncreaseDecreaseInNumberOfOrdinarySharesIssuedRelatedToUnderwrittenOfferings" name="IncreaseDecreaseInNumberOfOrdinarySharesIssuedRelatedToUnderwrittenOfferings" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_CommitmentsRelatedToRennesUniversityCollaborationResearchAgreementMember" name="CommitmentsRelatedToRennesUniversityCollaborationResearchAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_OutstandingShareExpirationPeriod" name="OutstandingShareExpirationPeriod" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_TreasurySharesHeld" name="TreasurySharesHeld" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ActuarialGainLossOnPostEmploymentBenefitObligationsMember" name="ActuarialGainLossOnPostEmploymentBenefitObligationsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_DilutiveEffectOfEarnoutSharesVested" name="DilutiveEffectOfEarnoutSharesVested" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_OrdinarySharePrice" name="OrdinarySharePrice" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_MaturityYearSevenMember" name="MaturityYearSevenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_DisclosureOtherCurrentAssetsAndAccruedIncomeAdditionalInformationDetailsTable" name="DisclosureOtherCurrentAssetsAndAccruedIncomeAdditionalInformationDetailsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_CurrentValueAddedTaxReceivablesAndInterestReceivable" name="CurrentValueAddedTaxReceivablesAndInterestReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_RestrictedStockUnitsOutstandingShareExpirationPeriod" name="RestrictedStockUnitsOutstandingShareExpirationPeriod" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_MaximumReimbursementOfDevelopmentRelatedCost" name="MaximumReimbursementOfDevelopmentRelatedCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_SupplementalNon-CashInvestingInformationAbstract" name="SupplementalNon-CashInvestingInformationAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_NonRefundableContractCostContribution" name="NonRefundableContractCostContribution" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_RestrictedStockUnitsGrantedSharesExpirationPeriod" name="RestrictedStockUnitsGrantedSharesExpirationPeriod" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ConditionalShareCapitalInConnectionWithEmployeeBenefitPlansMember" name="ConditionalShareCapitalInConnectionWithEmployeeBenefitPlansMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_IncreaseDecreaseInPotentialDefinedBenefitObligationDueToReasonablyPossibleIncreaseInActuarialAssumption" name="IncreaseDecreaseInPotentialDefinedBenefitObligationDueToReasonablyPossibleIncreaseInActuarialAssumption" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_BCAWarrantsMember" name="BCAWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_ForeignCurrencyRevaluation" name="ForeignCurrencyRevaluation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_RegisteredDirectOfferingMember" name="RegisteredDirectOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_SummaryOfCashAndCashEquivalentsTableTextBlock" name="SummaryOfCashAndCashEquivalentsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_StockOptionsMember" name="StockOptionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_DisclosureOfCurrentIncomeTaxExpenseAndDeferredTaxExpenseExplanatory" name="DisclosureOfCurrentIncomeTaxExpenseAndDeferredTaxExpenseExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_SharesOutstandingAndIssuedPriorToTheBusinessCombination" name="SharesOutstandingAndIssuedPriorToTheBusinessCombination" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_AccruedGeneralAndAdministrativeExpenseCurrent" name="AccruedGeneralAndAdministrativeExpenseCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_PeriodOfReasonablyPossibleDecreaseInActuarialAssumption" name="PeriodOfReasonablyPossibleDecreaseInActuarialAssumption" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ForfeitedSharesExpirationPeriod" name="ForfeitedSharesExpirationPeriod" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DilutiveEffectOfPublicWarrants" name="DilutiveEffectOfPublicWarrants" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ProceedsFromIssuingSharesFromConvertibleLoanAgreementInvestors" name="ProceedsFromIssuingSharesFromConvertibleLoanAgreementInvestors" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_WomenMember" name="WomenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_AggregateAmountOfPaymentsCommitted" name="AggregateAmountOfPaymentsCommitted" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_TaxEffectOfUseOfUnrecognizedTaxLosses" name="TaxEffectOfUseOfUnrecognizedTaxLosses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_BusinessCombinationsMergerAndListingExpense" name="BusinessCombinationsMergerAndListingExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_LegacyOculisMember" name="LegacyOculisMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_DisclosureOfResearchAndDevelopmentCommitmentsExplanatory" name="DisclosureOfResearchAndDevelopmentCommitmentsExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ExercisableShareExpirationPeriod" name="ExercisableShareExpirationPeriod" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DilutiveEffectOfRestrictedStockUnitsSubjectToFutureVesting" name="DilutiveEffectOfRestrictedStockUnitsSubjectToFutureVesting" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_LoanAgreementMember" name="LoanAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_ReclassificationAdjustmentsOnForeignCurrencyTranslationDifferencesRecycling" name="ReclassificationAdjustmentsOnForeignCurrencyTranslationDifferencesRecycling" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_OperatingExpensesMember" name="OperatingExpensesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_MergerAndListingExpense" name="MergerAndListingExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_FivePercentIncreaseInHKDMember" name="FivePercentIncreaseInHKDMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_MandatoryRetirementSavingsMember" name="MandatoryRetirementSavingsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_ListedPriceOfWarrantsPercentage" name="ListedPriceOfWarrantsPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_NominalValueOfTreasuryShares" name="NominalValueOfTreasuryShares" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_LeasingMember" name="LeasingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_Non-UtilizationFeePercent" name="Non-UtilizationFeePercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_MaturityYearEightMember" name="MaturityYearEightMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_MaturityYearFourMember" name="MaturityYearFourMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_AdjustedWeightedAverageSharesRestated" name="AdjustedWeightedAverageSharesRestated" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_EarnoutOptionsGrantedSharesExpirationPeriod" name="EarnoutOptionsGrantedSharesExpirationPeriod" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_FivePercentDecreaseInHKDMember" name="FivePercentDecreaseInHKDMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_EarnoutConsiderationIsSubjectToForfeitureTargetThree" name="EarnoutConsiderationIsSubjectToForfeitureTargetThree" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_IncreaseDecreaseInOperatingExpenses" name="IncreaseDecreaseInOperatingExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_AdditionsToLeaseLiabilities" name="AdditionsToLeaseLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_CommitmentsRelatedToAccureLicenseAgreementMember" name="CommitmentsRelatedToAccureLicenseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_AdjustmentsForDecreaseIncreaseInLongTermPayables" name="AdjustmentsForDecreaseIncreaseInLongTermPayables" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_PaymentsReceived" name="PaymentsReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_ClassAOrdinarySharesMember" name="ClassAOrdinarySharesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_USDollarCurrencyMember" name="USDollarCurrencyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_DisclosureOfAssumptionsUsedInTheBlackScholesOptionPricingModelForDeterminingTheFairValueOfTheWarrantsExplanatoryTableTextBlock" name="DisclosureOfAssumptionsUsedInTheBlackScholesOptionPricingModelForDeterminingTheFairValueOfTheWarrantsExplanatoryTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DisclosureOfCorporateInformationTextBlock" name="DisclosureOfCorporateInformationTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_RestrictedStockUnitsVestedSettledSharesExpirationPeriod" name="RestrictedStockUnitsVestedSettledSharesExpirationPeriod" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_PaymentOfObligatedNonRefundableCostContribution" name="PaymentOfObligatedNonRefundableCostContribution" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_OfficeFurnitureAndEquipmentMember" name="OfficeFurnitureAndEquipmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_AtTheMarketOfferingMember" name="AtTheMarketOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_WarrantAgreementMember" name="WarrantAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_FutureTemporaryDifferenceBetweenStatutoryAndCarryingValuesOfTransferredIntangibleAsset" name="FutureTemporaryDifferenceBetweenStatutoryAndCarryingValuesOfTransferredIntangibleAsset" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_IncreaseDecreaseThroughSharesIssuedRelatedToUnderwrittenOfferingsEquity" name="IncreaseDecreaseThroughSharesIssuedRelatedToUnderwrittenOfferingsEquity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_AccrualDueToClinicalTrialOfMilestones" name="AccrualDueToClinicalTrialOfMilestones" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_ServiceCostDefinedBenefitPlans" name="ServiceCostDefinedBenefitPlans" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_SummaryOfMaterialAccountingPoliciesTextBlock" name="SummaryOfMaterialAccountingPoliciesTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_EarnoutConsiderationIsSubjectToForfeitureTargetOne" name="EarnoutConsiderationIsSubjectToForfeitureTargetOne" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_FairValueOfWarrantOptionPricingModelLineItems" name="FairValueOfWarrantOptionPricingModelLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_IssuanceOfCommonStockUponExerciseOfPublicWarrantsPerShare" name="IssuanceOfCommonStockUponExerciseOfPublicWarrantsPerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ConditionalShareCapitalForEarnoutOptionsMember" name="ConditionalShareCapitalForEarnoutOptionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_FivePercentDecreaseInUSDMember" name="FivePercentDecreaseInUSDMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_SubsequentEventAfterReportingPeriodMember" name="SubsequentEventAfterReportingPeriodMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_IssuanceOfAssumedWarrantsShare" name="IssuanceOfAssumedWarrantsShare" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_FivePercentDecreaseInEuroMember" name="FivePercentDecreaseInEuroMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_FivePercentIncreaseInUSDMember" name="FivePercentIncreaseInUSDMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_IssuanceOfOrdinaryShares" name="IssuanceOfOrdinaryShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_FivePercentIncreaseInIslandicKronaMember" name="FivePercentIncreaseInIslandicKronaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_DescriptionOfAccountingPolicyOfNewStandardAndInterpretationsAdoptedExplanatory" name="DescriptionOfAccountingPolicyOfNewStandardAndInterpretationsAdoptedExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_LeaseLiabilitiesForeignCurrencyRevaluation" name="LeaseLiabilitiesForeignCurrencyRevaluation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_PrepaidClinicalAndTechnicalDevelopmentExpenses" name="PrepaidClinicalAndTechnicalDevelopmentExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_UpfrontPayment" name="UpfrontPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_LoanOneMember" name="LoanOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_ClassBOrdinarySharesMember" name="ClassBOrdinarySharesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_ScheduleOfPotentialDilutiveEffectNotIncludedInCalculationOfDilutedEarningsPerShareTextBlock" name="ScheduleOfPotentialDilutiveEffectNotIncludedInCalculationOfDilutedEarningsPerShareTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DisclosureOfPrincipalAssumptionsUsedForDeterminingPensionBenefitObligationsForGroupPlanExplanatory" name="DisclosureOfPrincipalAssumptionsUsedForDeterminingPensionBenefitObligationsForGroupPlanExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_PayrollAndRelatedPersonnelExpensesMember" name="PayrollAndRelatedPersonnelExpensesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_InterestReceivableRecordedInOtherCurrentAssets" name="InterestReceivableRecordedInOtherCurrentAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_ShareholdersEquityAbstract" name="ShareholdersEquityAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_PerSharePurchasePrice" name="PerSharePurchasePrice" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_EarnoutOptionsExercisable" name="EarnoutOptionsExercisable" type="xbrli:decimalItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_PercentageOfCommission" name="PercentageOfCommission" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ScheduleOfNetAssetsOfEbacTableTextBlock" name="ScheduleOfNetAssetsOfEbacTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_PayrollRelatedAccrualCurrent" name="PayrollRelatedAccrualCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_TriggeredMilestonePayment" name="TriggeredMilestonePayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_AdjustmentsForDecreaseIncreaseInPayablesAndAccruedLiabilities" name="AdjustmentsForDecreaseIncreaseInPayablesAndAccruedLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_MaturityYearOneMember" name="MaturityYearOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_TransactionCostsRelatedToRegisteredDirectOffering" name="TransactionCostsRelatedToRegisteredDirectOffering" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_IncreaseDecreaseThroughExerciseOfOptionsAndRestrictedShareUnitsVestedOrReleasedEquity" name="IncreaseDecreaseThroughExerciseOfOptionsAndRestrictedShareUnitsVestedOrReleasedEquity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_DisclosureOtherCurrentAssetsAndAccruedIncomeAdditionalInformationDetailsLineItems" name="DisclosureOtherCurrentAssetsAndAccruedIncomeAdditionalInformationDetailsLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_NumberOfShareEarnoutOptionsGrantedInShareBasedPaymentArrangement" name="NumberOfShareEarnoutOptionsGrantedInShareBasedPaymentArrangement" type="xbrli:decimalItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_CommitmentsForExternalResearchProjectsBetweenOneAndFiveYears" name="CommitmentsForExternalResearchProjectsBetweenOneAndFiveYears" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_ExpenseByEquitySettledShare-BasedPaymentTransactions" name="ExpenseByEquitySettledShare-BasedPaymentTransactions" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ConditionalShareCapitalForBCAPublicAndPrivateWarrantsMember" name="ConditionalShareCapitalForBCAPublicAndPrivateWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_PotentialNumberOfSharesIssuedInConnectionWithExerciseOfOptionRightsOrOtherEquityLinkedInstruments" name="PotentialNumberOfSharesIssuedInConnectionWithExerciseOfOptionRightsOrOtherEquityLinkedInstruments" type="xbrli:decimalItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_WeightedAverageSharesRestated" name="WeightedAverageSharesRestated" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_OtherCountryMember" name="OtherCountryMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_DescriptionOfAccountingPolicyOfCapitalizationOfTransactionCostsExplanatory" name="DescriptionOfAccountingPolicyOfCapitalizationOfTransactionCostsExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DirectOfferingMember" name="DirectOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_DisclosureOfBasisOfPreparationAbstract" name="DisclosureOfBasisOfPreparationAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_OfficeEquipmentAndHardwareMember" name="OfficeEquipmentAndHardwareMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_CommitmentsForExternalResearchProjectsNet" name="CommitmentsForExternalResearchProjectsNet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_CommitmentsForExternalResearchProjectsWithinOneYear" name="CommitmentsForExternalResearchProjectsWithinOneYear" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_PotentialIssuanceOfEquityInConnectionWithExerciseOfOptionRightsOrOtherEquityLinkedInstruments" name="PotentialIssuanceOfEquityInConnectionWithExerciseOfOptionRightsOrOtherEquityLinkedInstruments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_PeriodOfReasonablyPossibleIncreaseInActuarialAssumption" name="PeriodOfReasonablyPossibleIncreaseInActuarialAssumption" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_FixedRateOfPreferredDividendDeemedInterest" name="FixedRateOfPreferredDividendDeemedInterest" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_OfferingPriceOfShares" name="OfferingPriceOfShares" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_PercentageOfCapitalizedTransactionCostsForNewShares" name="PercentageOfCapitalizedTransactionCostsForNewShares" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_AdditionalShareBasedCompensationExpense" name="AdditionalShareBasedCompensationExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_AdjustmentsForIncreaseDecreaseInCashFlowsFromUsedInOperatingActivities" name="AdjustmentsForIncreaseDecreaseInCashFlowsFromUsedInOperatingActivities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_NumberOfManagedAndOperatedSegments" name="NumberOfManagedAndOperatedSegments" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_AdjustmentsForDecreaseIncreaseInOtherOperatingAssets" name="AdjustmentsForDecreaseIncreaseInOtherOperatingAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_KeyManagementPersonnelCompensationPayrollExpensesRelatedToRestrictedStock" name="KeyManagementPersonnelCompensationPayrollExpensesRelatedToRestrictedStock" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_NumberOfWorkPackages" name="NumberOfWorkPackages" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ExerciseOfPublicAndPrivateWarrants" name="ExerciseOfPublicAndPrivateWarrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_LeaseCommencementDate" name="LeaseCommencementDate" type="xbrli:dateItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_OtherCurrentAssetsOtherReceivableAndAccruedIncomeTextBlock" name="OtherCurrentAssetsOtherReceivableAndAccruedIncomeTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DefinedBenefitPlanGuaranteedInterestToBeCreditedToEmployeesSavings" name="DefinedBenefitPlanGuaranteedInterestToBeCreditedToEmployeesSavings" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ShareBasedCompensationPersonnelExpenseMember" name="ShareBasedCompensationPersonnelExpenseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_DisclosureOfRetroactivelyRestatedNumberOfSharesExplanatory" name="DisclosureOfRetroactivelyRestatedNumberOfSharesExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_IssuanceOfSharesInConnectionWithIncreaseInCash" name="IssuanceOfSharesInConnectionWithIncreaseInCash" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_DisclosureOfCashAndCashEquivalentsAndShortTermFinancialAssetsExplanatory" name="DisclosureOfCashAndCashEquivalentsAndShortTermFinancialAssetsExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_IncreaseDecreaseInGeneralAndAdministrationExpense" name="IncreaseDecreaseInGeneralAndAdministrationExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_PIPEInvestorsMember" name="PIPEInvestorsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_EffectOfOtherItems" name="EffectOfOtherItems" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_TransactionCostsRelatedToTheValueOfBusinessCombination" name="TransactionCostsRelatedToTheValueOfBusinessCombination" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_DilutiveEffectEarnoutOptionsOutstandingAndExercisable" name="DilutiveEffectEarnoutOptionsOutstandingAndExercisable" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DisclosureOfBasisOfPreparationAndChangesToGroupAccountingPoliciesTable" name="DisclosureOfBasisOfPreparationAndChangesToGroupAccountingPoliciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_TaxEffectOfUnrecognizedTaxLossesToOffsetTaxableIncome" name="TaxEffectOfUnrecognizedTaxLossesToOffsetTaxableIncome" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_ConversionOfLegacyOculisLongTermFinancialDebtIntoOculisOrdinaryShares" name="ConversionOfLegacyOculisLongTermFinancialDebtIntoOculisOrdinaryShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ShareBasedPaymentAwardVestingPeriod" name="ShareBasedPaymentAwardVestingPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ApplicableRateForTwentyTwentySixMember" name="ApplicableRateForTwentyTwentySixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_UnderwrittenOfferingMember" name="UnderwrittenOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_TaxesAtWeightedAverageIncomeTaxes" name="TaxesAtWeightedAverageIncomeTaxes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_AccruedIncomeFxRevaluation" name="AccruedIncomeFxRevaluation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_CapitalBandMember" name="CapitalBandMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_CapitalBand" name="CapitalBand" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_NetCashFlowsFromFinancingActivities" name="NetCashFlowsFromFinancingActivities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_GainLossRecognisedInProfitOrLossForeignCurrencyRiskNetExposure" name="GainLossRecognisedInProfitOrLossForeignCurrencyRiskNetExposure" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_TransactionCostsRelatedToThePublicOfferingValue" name="TransactionCostsRelatedToThePublicOfferingValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_MenMember" name="MenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_CommitmentsRelatedToNovartisLicenseAgreementMember" name="CommitmentsRelatedToNovartisLicenseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_WarrantsExpirationDate" name="WarrantsExpirationDate" type="xbrli:dateItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_IncreaseDecreaseThroughTreasuryShareTransactionsShares" name="IncreaseDecreaseThroughTreasuryShareTransactionsShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_MaturityOfGroupReportableLossesLineItems" name="MaturityOfGroupReportableLossesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_EarnoutConsiderationSharePriceTargetThree" name="EarnoutConsiderationSharePriceTargetThree" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_FairValueGainLossOnWarrantLiabilityShare" name="FairValueGainLossOnWarrantLiabilityShare" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_IncreaseDecreaseThroughExerciseOfOptionsAndRestrictedShareUnitsReleasedEquity" name="IncreaseDecreaseThroughExerciseOfOptionsAndRestrictedShareUnitsReleasedEquity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_NumberOfWarrantsOutstanding" name="NumberOfWarrantsOutstanding" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_WeightedAverageExercisePriceOfShareEarnoutOptionsGrantedInShareBasedPaymentArrangement" name="WeightedAverageExercisePriceOfShareEarnoutOptionsGrantedInShareBasedPaymentArrangement" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_PIPEAndCLAFinancingMember" name="PIPEAndCLAFinancingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognisedIntangibleAsset" name="DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognisedIntangibleAsset" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_CurrentBorrowingCapacity" name="CurrentBorrowingCapacity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_FivePercentIncreaseInEuroMember" name="FivePercentIncreaseInEuroMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_EffectOfNonTaxableIncome" name="EffectOfNonTaxableIncome" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_DescriptionOfAccountingPolicyForEarnoutConsiderationTextBlock" name="DescriptionOfAccountingPolicyForEarnoutConsiderationTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DilutiveEffectOfRestrictedStockSubjectToRepurchase" name="DilutiveEffectOfRestrictedStockSubjectToRepurchase" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_WarrantsPreviouslyGranted" name="WarrantsPreviouslyGranted" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_MaturityOfGroupReportableLossesTable" name="MaturityOfGroupReportableLossesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_AdjustmentsForDecreaseIncreaseInOtherOperatingAssetsAndLiabilities" name="AdjustmentsForDecreaseIncreaseInOtherOperatingAssetsAndLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_DescriptionOfAccountingPolicyOfGroupAccountingExplanatory" name="DescriptionOfAccountingPolicyOfGroupAccountingExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DisclosureOfDetailedInformationAboutAccruedExpensesAndOtherPayablesExplanatory" name="DisclosureOfDetailedInformationAboutAccruedExpensesAndOtherPayablesExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_OtherOperatingExpensesMember" name="OtherOperatingExpensesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_NumberOfShareOptionsExercisedAndRestrictedShareUnitsReleased" name="NumberOfShareOptionsExercisedAndRestrictedShareUnitsReleased" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_EarnoutConsiderationSharePriceTargetOne" name="EarnoutConsiderationSharePriceTargetOne" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_AmendedWarrantMember" name="AmendedWarrantMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_AdjustmentsForIncreaseDecreaseInCashFlowsFromUsedInFinancingActivities" name="AdjustmentsForIncreaseDecreaseInCashFlowsFromUsedInFinancingActivities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_DilutiveEffectOfSharesIncludingEarnoutOptions" name="DilutiveEffectOfSharesIncludingEarnoutOptions" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_TransactionCostsRecordedInAccruedExpensesAndOtherPayables" name="TransactionCostsRecordedInAccruedExpensesAndOtherPayables" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_PersonnelExpenseMember" name="PersonnelExpenseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_NumberOfSharesCancelled" name="NumberOfSharesCancelled" type="xbrli:decimalItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_TransactionCosts" name="TransactionCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_PaymentForShortTermFinancialAssetsClassifiedAsInvestingActivities" name="PaymentForShortTermFinancialAssetsClassifiedAsInvestingActivities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_IncreaseDecreaseThroughVestingOfEarnoutSharesEquityShares" name="IncreaseDecreaseThroughVestingOfEarnoutSharesEquityShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_AdditionalPaymentUponMilestonesReached" name="AdditionalPaymentUponMilestonesReached" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_ExerciseOfPublicAndPrivateWarrantsShare" name="ExerciseOfPublicAndPrivateWarrantsShare" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_PotentialNumberOfSharesIssuedInConnectionWithExerciseOfWarrants" name="PotentialNumberOfSharesIssuedInConnectionWithExerciseOfWarrants" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_RestrictedStockUnitsMember" name="RestrictedStockUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_WarrantLiabilitiesMember" name="WarrantLiabilitiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_ExercisedSharesExpirationPeriod" name="ExercisedSharesExpirationPeriod" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_LiabilityOccurredDueToClinicalTrialOfMilestones" name="LiabilityOccurredDueToClinicalTrialOfMilestones" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_FirstMilestonePayment" name="FirstMilestonePayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_DisclosureOfFinancingActivitiesExplanatory" name="DisclosureOfFinancingActivitiesExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_NumberOfWhollyOwnedSubsidiaries" name="NumberOfWhollyOwnedSubsidiaries" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_BusinessCombinationAgreementMember" name="BusinessCombinationAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_AdjustmentsForIncreaseDecreaseInCashFlowsFromUsedInInvestingActivities" name="AdjustmentsForIncreaseDecreaseInCashFlowsFromUsedInInvestingActivities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_ConvertibleLoanAgreementsMember" name="ConvertibleLoanAgreementsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_ConditionalShareCapitalForNewBondsAndSimilarDebtInstrumentsMember" name="ConditionalShareCapitalForNewBondsAndSimilarDebtInstrumentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_NumberOfSharesIssuedInExchangeOfSharesInBusinessAcquisition" name="NumberOfSharesIssuedInExchangeOfSharesInBusinessAcquisition" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_KreosCapitalVIIUKLimitedMember" name="KreosCapitalVIIUKLimitedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_BoardOfDirectorsMember" name="BoardOfDirectorsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_AdditionalUpfrontFeePayableUponReachingMilestone" name="AdditionalUpfrontFeePayableUponReachingMilestone" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_EarnoutConsiderationIsSubjectToForfeitureTargetTwo" name="EarnoutConsiderationIsSubjectToForfeitureTargetTwo" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DisclosureOfDetailedInFormationAboutWarrantLiabilityExplanatoryTableTextBlock" name="DisclosureOfDetailedInFormationAboutWarrantLiabilityExplanatoryTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ScheduleOfEstimatedUsefulLivesOfPropertyPlantAndEquipmentExplanatory" name="ScheduleOfEstimatedUsefulLivesOfPropertyPlantAndEquipmentExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_PercentageOfPossibleTax" name="PercentageOfPossibleTax" type="xbrli:pureItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_PublicOfferingMember" name="PublicOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_DisclosureOfAccruedIncomeExplanatory" name="DisclosureOfAccruedIncomeExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DilutiveEffectOfPrivateWarrants" name="DilutiveEffectOfPrivateWarrants" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_IncreaseDecreaseThroughVestingOfEarnoutSharesEquity" name="IncreaseDecreaseThroughVestingOfEarnoutSharesEquity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_AtTheMarketOfferingProgramMember" name="AtTheMarketOfferingProgramMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_FivePercentDecreaseInIslandicKronaMember" name="FivePercentDecreaseInIslandicKronaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_LossPerShareAbstract" name="LossPerShareAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_PotentialIssuanceOfEquityThroughShareBasedPaymentTransactions" name="PotentialIssuanceOfEquityThroughShareBasedPaymentTransactions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_PotentialNumberOfSharesIssuedFromConversionOfDebtInstruments" name="PotentialNumberOfSharesIssuedFromConversionOfDebtInstruments" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ShareExchangeRatio" name="ShareExchangeRatio" type="xbrli:decimalItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_PaymentOfFirstContractualNonRefundableCostContribution" name="PaymentOfFirstContractualNonRefundableCostContribution" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_DisclosureOfRetroactivelyRestatedNumberOfSharesExplanatoryAbstract" name="DisclosureOfRetroactivelyRestatedNumberOfSharesExplanatoryAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_ReimbursedCosts" name="ReimbursedCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_DilutiveEffectOfBlackrockWarrants" name="DilutiveEffectOfBlackrockWarrants" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_GrantedSharesExpirationPeriod" name="GrantedSharesExpirationPeriod" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_SwitzerlandPensionPlanMember" name="SwitzerlandPensionPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_CashAndCashEquivalentsAndShortTermFinancialAssetsTable" name="CashAndCashEquivalentsAndShortTermFinancialAssetsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_NonRefundableUpfrontFeePaid" name="NonRefundableUpfrontFeePaid" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_IncomeAndExpensesTable" name="IncomeAndExpensesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_ConditionalShareCapitalMember" name="ConditionalShareCapitalMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_PotentialIssuanceOfEquityThroughConversionOfDebtInstruments" name="PotentialIssuanceOfEquityThroughConversionOfDebtInstruments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_IssuanceOfSharesInConnectionWithValueWarrantExercises" name="IssuanceOfSharesInConnectionWithValueWarrantExercises" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_PotentialNumberOfSharesIssuedFromShareBasedPaymentTransactions" name="PotentialNumberOfSharesIssuedFromShareBasedPaymentTransactions" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ScheduleOfGeographicalAreasTableTextBlock" name="ScheduleOfGeographicalAreasTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_WarrantsVestedAndExercisable" name="WarrantsVestedAndExercisable" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_WeightedAverageRemainingContractualLifeOfOtherEquityInstrumentsOutstandingInShareBasedPaymentArrangement" name="WeightedAverageRemainingContractualLifeOfOtherEquityInstrumentsOutstandingInShareBasedPaymentArrangement" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_IssuanceOfSharesInConnectionWithReductionToWarrantLiability" name="IssuanceOfSharesInConnectionWithReductionToWarrantLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_AdjustmentsForMergerAndListingExpense" name="AdjustmentsForMergerAndListingExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_DisclosureOfGroupReportableLossesMaturityExplanatory" name="DisclosureOfGroupReportableLossesMaturityExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DisclosureOfQuantitativeInformationAboutLeaseLiabilitiesExplanatory" name="DisclosureOfQuantitativeInformationAboutLeaseLiabilitiesExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_OtherComprehensiveLossAbstract" name="OtherComprehensiveLossAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_ConversionOfOrdinaryShares" name="ConversionOfOrdinaryShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_RestrictedStockAwardsSubjectToRepurchase" name="RestrictedStockAwardsSubjectToRepurchase" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_FinancingActivitiesDisclosureAbstract" name="FinancingActivitiesDisclosureAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_MergerAndListingExpenseOperatingExpensesMember" name="MergerAndListingExpenseOperatingExpensesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_DisclosureOfReconciliationOfAccountingProfitMultipliedByApplicableTaxRatesExplanatory" name="DisclosureOfReconciliationOfAccountingProfitMultipliedByApplicableTaxRatesExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_EarnoutConsiderationSharePriceTargetTwo" name="EarnoutConsiderationSharePriceTargetTwo" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_NumberOfWarrantExercised" name="NumberOfWarrantExercised" type="xbrli:decimalItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_NumberOfStockAppreciationRightsGrantedInSharebasedPaymentArrangement" name="NumberOfStockAppreciationRightsGrantedInSharebasedPaymentArrangement" type="xbrli:decimalItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_IssuanceOfOrdinarySharesToPipeInvestors" name="IssuanceOfOrdinarySharesToPipeInvestors" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ScheduleOfTradePayables" name="ScheduleOfTradePayables" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ActuarialLossOnPostEmploymentBenefitObligations" name="ActuarialLossOnPostEmploymentBenefitObligations" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_RedemptionOptionAmountEquivalentToInvestorsInvestmentAccruedDividendAndCompoundInterestAmount" name="RedemptionOptionAmountEquivalentToInvestorsInvestmentAccruedDividendAndCompoundInterestAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognisedPension" name="DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognisedPension" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_LoansFeePayable" name="LoansFeePayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_PercentageOfDebtToMarketCapRatio" name="PercentageOfDebtToMarketCapRatio" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_EuroCurrencyMember" name="EuroCurrencyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_MaturityYearThreeMember" name="MaturityYearThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_IssuanceOfSharesInConnectionWithWarrantExercises" name="IssuanceOfSharesInConnectionWithWarrantExercises" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_WarrantsIssuedPricePerShare" name="WarrantsIssuedPricePerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_LaboratoryEquipmentMember" name="LaboratoryEquipmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_CorporateInformationAbstract" name="CorporateInformationAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_AccruedResearchAndDevelopmentExpenseCurrent" name="AccruedResearchAndDevelopmentExpenseCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_NumberOfIndividuals" name="NumberOfIndividuals" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognisedLeasing" name="DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognisedLeasing" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ExercisePrice" name="ExercisePrice" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_IcelandAndUnitedStatesFacilitiesMember" name="IcelandAndUnitedStatesFacilitiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_DisclosureOfOtherCurrentAssetsAndOtherReceivablesExplanatory" name="DisclosureOfOtherCurrentAssetsAndOtherReceivablesExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_AccruedIncomeRecognized" name="AccruedIncomeRecognized" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_DescriptionOfAccountingPolicyOfCurrentVersusNoncurrentClassificationExplanatory" name="DescriptionOfAccountingPolicyOfCurrentVersusNoncurrentClassificationExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_FollowOnPublicOfferingMember" name="FollowOnPublicOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_DisclosureOfBasisOfPreparationAndChangesToGroupAccountingPoliciesAbstract" name="DisclosureOfBasisOfPreparationAndChangesToGroupAccountingPoliciesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_DefinedBenefitPlanApplicableRateForConvertingMandatorySavings" name="DefinedBenefitPlanApplicableRateForConvertingMandatorySavings" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DepreciationExpenseMember" name="DepreciationExpenseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_WeightedAverageExercisePriceOfShareOptionsVestedSettledInSharebasedPaymentArrangement2019" name="WeightedAverageExercisePriceOfShareOptionsVestedSettledInSharebasedPaymentArrangement2019" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_ExternalServiceProvidersOperatingExpensesMember" name="ExternalServiceProvidersOperatingExpensesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_AmendedBlackrockWarrantMember" name="AmendedBlackrockWarrantMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_IssuanceOfWarrants" name="IssuanceOfWarrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_DisclosureOfComponentsOfNetBenefitExpenseExplanatory" name="DisclosureOfComponentsOfNetBenefitExpenseExplanatory" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_DefinedBenefitPlanPlanAssetsInsuranceCoverageParentage" name="DefinedBenefitPlanPlanAssetsInsuranceCoverageParentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_MaturityYearSixMember" name="MaturityYearSixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_FairValueGainLossOnWarrantLiability" name="FairValueGainLossOnWarrantLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_SupplementalNonCashFinancingInformationAbstract" name="SupplementalNonCashFinancingInformationAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_LoanTwoMember" name="LoanTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_DefinedBenefitPlanApplicableRateForConvertingSupplementarySavings" name="DefinedBenefitPlanApplicableRateForConvertingSupplementarySavings" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_AmountCapitalizedInDeductionOfSharePremiumEquity" name="AmountCapitalizedInDeductionOfSharePremiumEquity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_IcelandKronaCurrencyMember" name="IcelandKronaCurrencyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ocs_CancellationOfTreasuryShares1" name="CancellationOfTreasuryShares1" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ocs_IncreaseDecreaseInResearchAndDevelopmentExpense" name="IncreaseDecreaseInResearchAndDevelopmentExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_ProceedsFromEBACNonRedeemedShareholders" name="ProceedsFromEBACNonRedeemedShareholders" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_AdjustmentsForDecreaseIncreaseInAccruedExpensesAndOtherPayables" name="AdjustmentsForDecreaseIncreaseInAccruedExpensesAndOtherPayables" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ocs_TransactionsCostsRelatedToFinancingActivities" name="TransactionsCostsRelatedToFinancingActivities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ocs_IncreaseDecreaseInWarrantLiability" name="IncreaseDecreaseInWarrantLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
</xsd:schema>
