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  <xs:element id="fivn_USGovernmentAgenciesAndUSGovernmentSponsoredEnterprisesDebtSecuritiesMember" abstract="true" name="USGovernmentAgenciesAndUSGovernmentSponsoredEnterprisesDebtSecuritiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_DebtInstrumentInterestRateStatedPercentageAdditionalInterest" abstract="false" name="DebtInstrumentInterestRateStatedPercentageAdditionalInterest" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="fivn_ClosingPriceOfCommonStock" abstract="false" name="ClosingPriceOfCommonStock" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="fivn_LesseeOperatingLeaseLeaseNotYetCommencedAmount" abstract="false" name="LesseeOperatingLeaseLeaseNotYetCommencedAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_DebtInstrumentConvertibleTermAxis" abstract="true" name="DebtInstrumentConvertibleTermAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="fivn_FinancialStatementComponentsAbstract" abstract="true" name="FinancialStatementComponentsAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="fivn_DebtInstrumentPremiumOnConversionPriceInRelationToClosingPrice" abstract="false" name="DebtInstrumentPremiumOnConversionPriceInRelationToClosingPrice" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="fivn_LongTermMarketableInvestmentsMember" abstract="true" name="LongTermMarketableInvestmentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_HostingandTelecommunicationsAgreementMember" abstract="true" name="HostingandTelecommunicationsAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_DebtInstrumentRedemptionMultipleofPrinciple" abstract="false" name="DebtInstrumentRedemptionMultipleofPrinciple" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_DebtInstrumentOptionToPurchaseAdditionalDebtThroughPrivateOffering" abstract="false" name="DebtInstrumentOptionToPurchaseAdditionalDebtThroughPrivateOffering" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_ConvertibleSeniorNotesDue2023Member" abstract="true" name="ConvertibleSeniorNotesDue2023Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_DebtSecuritiesAvailableForSaleMaturityAllocatedAndSingleMaturityDateAfterOneYearAmortizedCost" abstract="false" name="DebtSecuritiesAvailableForSaleMaturityAllocatedAndSingleMaturityDateAfterOneYearAmortizedCost" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_ExecutiveEmploymentTerminatesDueToDisabilityByEndOf2024Member" abstract="true" name="ExecutiveEmploymentTerminatesDueToDisabilityByEndOf2024Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThenOptionsWeightedAverageGrantDateFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThenOptionsWeightedAverageGrantDateFairValue" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
