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  <xs:element id="pubm_TemporaryEquityValueCashlessExerciseOfPreferredStockWarrants" abstract="false" name="TemporaryEquityValueCashlessExerciseOfPreferredStockWarrants" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pubm_OperatingLeaseAssetsAndLiabilitiesLesseeAbstract" abstract="true" name="OperatingLeaseAssetsAndLiabilitiesLesseeAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="pubm_IncrementalCommonSharesAttributableToDilutiveEffectOfWarrants" abstract="false" name="IncrementalCommonSharesAttributableToDilutiveEffectOfWarrants" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="pubm_BuyerOneMember" abstract="true" name="BuyerOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
