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  <xs:element id="opy_DisclosureScheduleOfFairValuesOfOutstandingDerivativeContractsRecordedAsLiabilitiesAbstract" abstract="true" name="DisclosureScheduleOfFairValuesOfOutstandingDerivativeContractsRecordedAsLiabilitiesAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="opy_PrivateEquitySecuritiesMember" abstract="true" name="PrivateEquitySecuritiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opy_FinancialInstrumentsEstimateNotPracticableFairValueTable" abstract="true" name="FinancialInstrumentsEstimateNotPracticableFairValueTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="opy_FinancialInstrumentsEstimateNotPracticableFairValueLineItems" abstract="true" name="FinancialInstrumentsEstimateNotPracticableFairValueLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="opy_FairValueEstimateNotPracticableCashAndCashEquivalents" abstract="false" name="FairValueEstimateNotPracticableCashAndCashEquivalents" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueEstimateNotPracticableDepositsWithClearingOrganizations" abstract="false" name="FairValueEstimateNotPracticableDepositsWithClearingOrganizations" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueEstimateNotPracticableDepositsPaidForSecuritiesBorrowed" abstract="false" name="FairValueEstimateNotPracticableDepositsPaidForSecuritiesBorrowed" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueEstimateNotPracticableDueFromCorrespondentBrokers" abstract="false" name="FairValueEstimateNotPracticableDueFromCorrespondentBrokers" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueEstimateNotPracticableSecuritiesFailedToDeliver" abstract="false" name="FairValueEstimateNotPracticableSecuritiesFailedToDeliver" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueEstimateNotPracticableReceivablesFromClearingOrganizations" abstract="false" name="FairValueEstimateNotPracticableReceivablesFromClearingOrganizations" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueEstimateNotPracticableReceivablesFromTradeReceivables" abstract="false" name="FairValueEstimateNotPracticableReceivablesFromTradeReceivables" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueEstimateNotPracticableReceivablesFromOther" abstract="false" name="FairValueEstimateNotPracticableReceivablesFromOther" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueEstimateNotPracticableReceivablesFromBrokersDealersAndClearingOrganizations" abstract="false" name="FairValueEstimateNotPracticableReceivablesFromBrokersDealersAndClearingOrganizations" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueEstimateNotPracticableReceivablesFromCustomers" abstract="false" name="FairValueEstimateNotPracticableReceivablesFromCustomers" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueEstimateNotPracticableNotesReceivableNet" abstract="false" name="FairValueEstimateNotPracticableNotesReceivableNet" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueEstimateNotPracticableInvestment" abstract="false" name="FairValueEstimateNotPracticableInvestment" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueEstimateNotPracticableDraftsPayable" abstract="false" name="FairValueEstimateNotPracticableDraftsPayable" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueEstimateNotPracticableBankLoans" abstract="false" name="FairValueEstimateNotPracticableBankLoans" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueEstimateNotPracticableDepositsReceivedForSecuritiesLoaned" abstract="false" name="FairValueEstimateNotPracticableDepositsReceivedForSecuritiesLoaned" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueEstimateNotPracticablePayableToCorrespondentBrokers" abstract="false" name="FairValueEstimateNotPracticablePayableToCorrespondentBrokers" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueEstimateNotPracticableSecuritiesFailedToReceive" abstract="false" name="FairValueEstimateNotPracticableSecuritiesFailedToReceive" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueEstimateNotPracticableOtherPayablesToBrokerDealersAndClearingOrganizations" abstract="false" name="FairValueEstimateNotPracticableOtherPayablesToBrokerDealersAndClearingOrganizations" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueEstimateNotPracticablePayablesToBrokerDealersAndClearingOrganizations" abstract="false" name="FairValueEstimateNotPracticablePayablesToBrokerDealersAndClearingOrganizations" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueEstimateNotPracticablePayablesToCustomers" abstract="false" name="FairValueEstimateNotPracticablePayablesToCustomers" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueEstimatenotPracticableSecuritiessoldunderAgreementstoRepurchase" abstract="false" name="FairValueEstimatenotPracticableSecuritiessoldunderAgreementstoRepurchase" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_GainLossOnDerivativesPreTaxRecognizedInIncome" abstract="false" name="GainLossOnDerivativesPreTaxRecognizedInIncome" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_ReverseRepurchaseAgreementMember" abstract="true" name="ReverseRepurchaseAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opy_SecuritiesBorrowedTransactionsMember" abstract="true" name="SecuritiesBorrowedTransactionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opy_A2LargestCustomersMember" abstract="true" name="A2LargestCustomersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opy_FirmsSecuritiesFairValueCollateralForBankLoans" abstract="false" name="FirmsSecuritiesFairValueCollateralForBankLoans" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_CustomerSecuritiesUnderCustomerMarginLoansThatAreAvailableToBePledged" abstract="false" name="CustomerSecuritiesUnderCustomerMarginLoansThatAreAvailableToBePledged" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_CustomerSecuritiesUnderCustomerMarginLoansThatAreAvailableToBePledgedRePledgedAmount" abstract="false" name="CustomerSecuritiesUnderCustomerMarginLoansThatAreAvailableToBePledgedRePledgedAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_CustomerSecuritiesDirectlyWithTheOptionsClearingCorporationToSecureObligationsAndMarginRequirementsUnderOptionContractsWrittenByCustomers" abstract="false" name="CustomerSecuritiesDirectlyWithTheOptionsClearingCorporationToSecureObligationsAndMarginRequirementsUnderOptionContractsWrittenByCustomers" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueOfSecuritiesReceivedAsCollateralUnderSecuritiesBorrowedTransactions" abstract="false" name="FairValueOfSecuritiesReceivedAsCollateralUnderSecuritiesBorrowedTransactions" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_FairValueOfSecuritiesReceivedAsCollateralSoldAndRePledgedUnderSecuritiesLoaned" abstract="false" name="FairValueOfSecuritiesReceivedAsCollateralSoldAndRePledgedUnderSecuritiesLoaned" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_ReceivablesFromBrokersDealersAndClearingOrganizationsNumberOfMajorBrokerDealers" abstract="false" name="ReceivablesFromBrokersDealersAndClearingOrganizationsNumberOfMajorBrokerDealers" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="opy_CreditConcentrationReceivableFromMajorBrokerDealers" abstract="false" name="CreditConcentrationReceivableFromMajorBrokerDealers" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_ReceivableFromCustomerInBrokerageNumberOfCustomers" abstract="false" name="ReceivableFromCustomerInBrokerageNumberOfCustomers" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="opy_CreditConcentrationReceivableFromCustomerInBrokerage" abstract="false" name="CreditConcentrationReceivableFromCustomerInBrokerage" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_TransactionSettlementPeriod" abstract="false" name="TransactionSettlementPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="opy_ShareRepurchaseProgramMarch2024Member" abstract="true" name="ShareRepurchaseProgramMarch2024Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opy_NewProgramMember" abstract="true" name="NewProgramMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opy_StockRepurchaseProgramPercentageOfSharesRepurchaseOfOutstandingShare" abstract="false" name="StockRepurchaseProgramPercentageOfSharesRepurchaseOfOutstandingShare" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opy_StockRepurchasedandRetiredDuringPeriodPerShare" abstract="false" name="StockRepurchasedandRetiredDuringPeriodPerShare" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="opy_ChangeInCommonStockOutstandingRollForward" abstract="true" name="ChangeInCommonStockOutstandingRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="opy_LibertyCapitalGroupIndividuallyAndOnBehalfOfAllOthersSimilarlySituatedV.OppenheimerHoldingsInc.OppenheimerCo.Inc.AndOppenheimerAssetManagementInc.Member" abstract="true" name="LibertyCapitalGroupIndividuallyAndOnBehalfOfAllOthersSimilarlySituatedV.OppenheimerHoldingsInc.OppenheimerCo.Inc.AndOppenheimerAssetManagementInc.Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opy_OppenheimerMember" abstract="true" name="OppenheimerMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opy_OppenheimerEuropeMember" abstract="true" name="OppenheimerEuropeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opy_OppenheimerInvestmentsAsiaMember" abstract="true" name="OppenheimerInvestmentsAsiaMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opy_RegulatoryCapitalRequirementAxis" abstract="true" name="RegulatoryCapitalRequirementAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="opy_RegulatoryCapitalRequirementDomain" abstract="true" name="RegulatoryCapitalRequirementDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opy_BaselThreeNewRequirementsMember" abstract="true" name="BaselThreeNewRequirementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opy_BrokerDealMinimumNetCapitalRequirementParent" abstract="false" name="BrokerDealMinimumNetCapitalRequirementParent" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opy_PercentageOfNetCapitalToAggregateIndebtedness" abstract="false" name="PercentageOfNetCapitalToAggregateIndebtedness" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opy_BankingRegulationCommonEquityTierOneRatio" abstract="false" name="BankingRegulationCommonEquityTierOneRatio" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opy_CommonEquityTierOneRatioRequiredUnderCrdFourth" abstract="false" name="CommonEquityTierOneRatioRequiredUnderCrdFourth" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opy_TierOneCapitalRatioCalculatedUnderCrdFourth" abstract="false" name="TierOneCapitalRatioCalculatedUnderCrdFourth" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opy_TierOneCapitalRatioRequiredUnderCrdFourth" abstract="false" name="TierOneCapitalRatioRequiredUnderCrdFourth" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opy_TotalCapitalRatioCalculatedUnderCrdFourth" abstract="false" name="TotalCapitalRatioCalculatedUnderCrdFourth" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opy_TotalCapitalRatioRequiredUnderCrdFourth" abstract="false" name="TotalCapitalRatioRequiredUnderCrdFourth" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opy_LiquidCapitalUnderHongKongSFCRules" abstract="false" name="LiquidCapitalUnderHongKongSFCRules" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_ExcessLiquidCapitalUnderHongKongSFCRules" abstract="false" name="ExcessLiquidCapitalUnderHongKongSFCRules" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opy_NumberOfReportableSegmentsNotDisclosedFlag" abstract="false" name="NumberOfReportableSegmentsNotDisclosedFlag" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="opy_EuropeMiddleEastMember" abstract="true" name="EuropeMiddleEastMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
