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<!-- Round: 4 -->
<!-- Creation date: 2017-07-27T17:38:07Z -->
<!-- Copyright (c) 2017 Donnelley Financial, LLC. All Rights Reserved. -->
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  <element name="DocumentAndEntityInformationAbstract" id="spsc_DocumentAndEntityInformationAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EmployeeStockPurchasePlanEmployeesContribution" id="spsc_EmployeeStockPurchasePlanEmployeesContribution" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EmployeeStockPurchasePlanMember" id="spsc_EmployeeStockPurchasePlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncreaseDecreaseInDeferredRent" id="spsc_IncreaseDecreaseInDeferredRent" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfOfferings" id="spsc_NumberOfOfferings" type="xbrli:integerItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PaymentsToAcquireBusinessesAndIntangibleAssetsNetOfCashAcquired" id="spsc_PaymentsToAcquireBusinessesAndIntangibleAssetsNetOfCashAcquired" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PerformanceShareUnitsMember" id="spsc_PerformanceShareUnitsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RegulatoryAssetsAbstract" id="spsc_RegulatoryAssetsAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RestrictedStockUnitsAndPerformanceShareUnitsMember" id="spsc_RestrictedStockUnitsAndPerformanceShareUnitsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RetainedEarningsAccumulatedDeficitMember" id="spsc_RetainedEarningsAccumulatedDeficitMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfAccountingPoliciesLineItems" id="spsc_ScheduleOfAccountingPoliciesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfAccountingPoliciesTable" id="spsc_ScheduleOfAccountingPoliciesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndUnissuedInPeriod" id="spsc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndUnissuedInPeriod" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SignificantAccountingPoliciesPolicyTextBlock" id="spsc_SignificantAccountingPoliciesPolicyTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SubscriberRelationshipsMember" id="spsc_SubscriberRelationshipsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TechnologyAndOtherMember" id="spsc_TechnologyAndOtherMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TwoThousandTenMember" id="spsc_TwoThousandTenMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
</schema>
