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  <xs:element id="pubm_MartinMember" abstract="true" name="MartinMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pubm_IrrevocableLettersOfCreditDueJuly2028Member" abstract="true" name="IrrevocableLettersOfCreditDueJuly2028Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pubm_IrrevocableLettersOfCreditDueSeptember2031Member" abstract="true" name="IrrevocableLettersOfCreditDueSeptember2031Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pubm_NumberOfDebtInstruments" abstract="false" name="NumberOfDebtInstruments" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pubm_A2023RepurchaseProgramMember" abstract="true" name="A2023RepurchaseProgramMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pubm_A2024RepurchaseProgramMember" abstract="true" name="A2024RepurchaseProgramMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pubm_A2025RepurchaseProgramMember" abstract="true" name="A2025RepurchaseProgramMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pubm_ShareRepurchaseProgramAdditionalAuthorizedAmount" abstract="false" name="ShareRepurchaseProgramAdditionalAuthorizedAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pubm_StockRepurchaseProgramNetShareRepurchasesChargeInflationReductionAct" abstract="false" name="StockRepurchaseProgramNetShareRepurchasesChargeInflationReductionAct" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pubm_ShareBasedCompensationArrangementAutomaticAnnualIncreaseTerm" abstract="false" name="ShareBasedCompensationArrangementAutomaticAnnualIncreaseTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pubm_ShareBasedCompensationArrangementByShareBasedPaymentAwardAmountWithheldForEmployeeStockPurchasePlan" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAmountWithheldForEmployeeStockPurchasePlan" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pubm_ESPPMember" abstract="true" name="ESPPMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pubm_ShareBasedPaymentArrangementTaxBenefit" abstract="false" name="ShareBasedPaymentArrangementTaxBenefit" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pubm_ShareBasedPaymentArrangementExpenseNet" abstract="false" name="ShareBasedPaymentArrangementExpenseNet" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pubm_IncrementalCommonSharesAttributableToDilutiveEffectOfCallOptions" abstract="false" name="IncrementalCommonSharesAttributableToDilutiveEffectOfCallOptions" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="pubm_IncrementalCommonSharesAttributableToRestrictedStock" abstract="false" name="IncrementalCommonSharesAttributableToRestrictedStock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="pubm_IncrementalCommonSharesAttributableToEmployeeStockPurchasePlan" abstract="false" name="IncrementalCommonSharesAttributableToEmployeeStockPurchasePlan" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="pubm_DeferredIncomeTaxExpenseBenefitExcludingNetDeferredTaxLiabilityFromAcquisition" abstract="false" name="DeferredIncomeTaxExpenseBenefitExcludingNetDeferredTaxLiabilityFromAcquisition" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pubm_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseCompensationAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseCompensationAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pubm_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseAcquisitionRelatedCostAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseAcquisitionRelatedCostAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pubm_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseCompensationPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseCompensationPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="pubm_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseAcquisitionRelatedCostPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseAcquisitionRelatedCostPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="pubm_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShortfallShareBasedPaymentArrangementAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShortfallShareBasedPaymentArrangementAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pubm_EffectiveIncomeTaxRateReconciliationTransferPricingReservePercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationTransferPricingReservePercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="pubm_EffectiveIncomeTaxRateReconciliationDeductionCoverEmployeesPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationDeductionCoverEmployeesPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="pubm_EffectiveIncomeTaxRateReconciliationAcquisitionRelatedCosts" abstract="false" name="EffectiveIncomeTaxRateReconciliationAcquisitionRelatedCosts" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="pubm_DeferredTaxAssetsLeaseObligation" abstract="false" name="DeferredTaxAssetsLeaseObligation" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pubm_DeferredTaxLiabilitiesRightOfUseAsset" abstract="false" name="DeferredTaxLiabilitiesRightOfUseAsset" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pubm_FederalTaxCreditCarryforwardMember" abstract="true" name="FederalTaxCreditCarryforwardMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pubm_NewYorkCityMember" abstract="true" name="NewYorkCityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pubm_CashPaidForIncomeTaxes" abstract="false" name="CashPaidForIncomeTaxes" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pubm_ReportableSegmentMember" abstract="true" name="ReportableSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pubm_RestOfTheWorldMember" abstract="true" name="RestOfTheWorldMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
