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  <xs:element id="fivn_DebtSecuritiesAvailableForSaleAccumulatedGrossUnrealizedGainBeforeTaxNoncurrent" abstract="false" name="DebtSecuritiesAvailableForSaleAccumulatedGrossUnrealizedGainBeforeTaxNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_AssetAcquisitionDomain" abstract="true" name="AssetAcquisitionDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="fivn_ScheduleOfNetImpactOnEquityComponentsFromIssuanceOfNotesTableTextBlock" abstract="false" name="ScheduleOfNetImpactOnEquityComponentsFromIssuanceOfNotesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="fivn_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization" abstract="false" name="PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_LesseeOperatingLeaseRentAbatementPeriod" abstract="false" name="LesseeOperatingLeaseRentAbatementPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="fivn_DebtInstrumentConversionMultipleOfAggregatePrincipalAmount" abstract="false" name="DebtInstrumentConversionMultipleOfAggregatePrincipalAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_AdjustmentsToAdditionalPaidInCapitalCarryingAmountOfEquityEquityComponentOfConvertibleDebt" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalCarryingAmountOfEquityEquityComponentOfConvertibleDebt" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_ScheduleOfBalanceSheetInformationRelatedToLeasesTableTextBlock" abstract="false" name="ScheduleOfBalanceSheetInformationRelatedToLeasesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="fivn_PaymentsToAcquireAssetsAsPartOfAnAssetAcquisition" abstract="false" name="PaymentsToAcquireAssetsAsPartOfAnAssetAcquisition" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_ConversionFeatureAxis" abstract="true" name="ConversionFeatureAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="fivn_AccruedLiabilitiesandOtherCurrentLiabilities" abstract="false" name="AccruedLiabilitiesandOtherCurrentLiabilities" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization" abstract="false" name="PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_FinanceLeaseRightOfUseAssetAccumulatedDepreciation" abstract="false" name="FinanceLeaseRightOfUseAssetAccumulatedDepreciation" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_FinanceLeaseRightOfUseAssetBeforeAccumulatedAmortization" abstract="false" name="FinanceLeaseRightOfUseAssetBeforeAccumulatedAmortization" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_DebtSecuritiesAvailableForSaleAccumulatedGrossUnrealizedGainBeforeTaxCurrent" abstract="false" name="DebtSecuritiesAvailableForSaleAccumulatedGrossUnrealizedGainBeforeTaxCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_ContractAcquisitionCostsMember" abstract="true" name="ContractAcquisitionCostsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="fivn_OperatingLeaseRightOfUseAssetAmortizationExpense" abstract="false" name="OperatingLeaseRightOfUseAssetAmortizationExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_LesseeOperatingLeaseOptionToTerminateNotice" abstract="false" name="LesseeOperatingLeaseOptionToTerminateNotice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="fivn_CapitalizationofLeaseholdImprovementThroughNonCashLeaseIncentive" abstract="false" name="CapitalizationofLeaseholdImprovementThroughNonCashLeaseIncentive" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_FinanceLeaseRightOfUseAssetGross" abstract="false" name="FinanceLeaseRightOfUseAssetGross" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_AccruedFederalFees" abstract="false" name="AccruedFederalFees" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <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_ConversionFeatureDomain" abstract="true" name="ConversionFeatureDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="fivn_DebtInstrumentConvertibleConversionPricePerShareRequiringConversion" abstract="false" name="DebtInstrumentConvertibleConversionPricePerShareRequiringConversion" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="num:perShareItemType"/>
  <xs:element id="fivn_VirtualObserverMember" abstract="true" name="VirtualObserverMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="fivn_FinanceLeaseCost" abstract="false" name="FinanceLeaseCost" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_DebtInstrumentConvertibleTermTwoMember" abstract="true" name="DebtInstrumentConvertibleTermTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="fivn_ClosingPriceOfCommonStock" abstract="false" name="ClosingPriceOfCommonStock" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="num:perShareItemType"/>
  <xs:element id="fivn_DebtInstrumentConversionOptionEquityComponent" abstract="false" name="DebtInstrumentConversionOptionEquityComponent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_LesseeOperatingLeaseRentalSpace" abstract="false" name="LesseeOperatingLeaseRentalSpace" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="num:areaItemType"/>
  <xs:element id="fivn_IssuanceCostsMember" abstract="true" name="IssuanceCostsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="fivn_CarryingValueOfDebtSubjectToRepurchaseNet" abstract="false" name="CarryingValueOfDebtSubjectToRepurchaseNet" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_CumulativeEffectPeriodOfAdoptionDomain" abstract="true" name="CumulativeEffectPeriodOfAdoptionDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="fivn_SharePriceOfCommonStockWithConversionPremium" abstract="false" name="SharePriceOfCommonStockWithConversionPremium" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="num:perShareItemType"/>
  <xs:element id="fivn_DebtInstrumentIssuanceCostsEquityComponent" abstract="false" name="DebtInstrumentIssuanceCostsEquityComponent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_StockholdersEquityCapitalStructureTable" abstract="true" name="StockholdersEquityCapitalStructureTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
</xs:schema>
