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<!-- DFS ActiveDisclosure(SM) XBRL Schema Document - http://www.dfsco.com/financial-services/ -->
<!-- Creation Date      : 2018-11-07T02:57:21.7046165+00:00 -->
<!-- Version            : 3.1.6852.22116 -->
<!-- Package ID         : 1fa621997469459890b481d4ac758ff0 -->
<!-- Copyright (c) 2018 Donnelley Financial, LLC. All Rights Reserved. -->
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  <element id="ttd_ScheduleOfGrossBillingsBasedOnBillingOfClientsAffiliatesTableTextBox" name="ScheduleOfGrossBillingsBasedOnBillingOfClientsAffiliatesTableTextBox" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <element id="ttd_CommonStockNumberOfClasses" name="CommonStockNumberOfClasses" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <element id="ttd_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceAndAdditionalDisclosuresAbstract" name="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceAndAdditionalDisclosuresAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="ttd_TwoThousandAndSixteenIncentiveAwardPlanMember" name="TwoThousandAndSixteenIncentiveAwardPlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="ttd_CommitmentsAbstract" name="CommitmentsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="ttd_SwinglineBorrowingsMember" name="SwinglineBorrowingsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="ttd_SecondAAndRCreditFacilityMember" name="SecondAAndRCreditFacilityMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="ttd_LineOfCreditAdditionalBorrowingCapacity" name="LineOfCreditAdditionalBorrowingCapacity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <element id="ttd_LineOfCreditFacilityCovenantRatio" name="LineOfCreditFacilityCovenantRatio" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
</schema>
