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  <xs:element id="fivn_DeferredTaxAssetsOperatingLossandTaxCreditCarryforwardsTotal" abstract="false" name="DeferredTaxAssetsOperatingLossandTaxCreditCarryforwardsTotal" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_CapitalizationOfLeaseholdImprovementThroughLeaseIncentive" abstract="false" name="CapitalizationOfLeaseholdImprovementThroughLeaseIncentive" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <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_PaymentsForCappedCallTransactionsFinancingActivities" abstract="false" name="PaymentsForCappedCallTransactionsFinancingActivities" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_DeferredTaxLiabilitiesRightOfUseAssets" abstract="false" name="DeferredTaxLiabilitiesRightOfUseAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_ShareBasedCompensationArrangementByShareBasedPaymentAwardESPPOfferingPeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardESPPOfferingPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <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_DebtInstrumentInterestRateStatedPercentageAdditionalInterest" abstract="false" name="DebtInstrumentInterestRateStatedPercentageAdditionalInterest" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <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_CommonStockCapitalSharesReservedforFutureIssuanceAnnualIncreasePercentage" abstract="false" name="CommonStockCapitalSharesReservedforFutureIssuanceAnnualIncreasePercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="fivn_DebtInstrumentConvertibleCappedCallTransactionsCapPrice" abstract="false" name="DebtInstrumentConvertibleCappedCallTransactionsCapPrice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="fivn_BishopRanchBuildingLeaseMember" abstract="true" name="BishopRanchBuildingLeaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_LeaseArrangementsDomain" abstract="true" name="LeaseArrangementsDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_SharePriceOfCommonStockWithConversionPremium" abstract="false" name="SharePriceOfCommonStockWithConversionPremium" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="fivn_EquityIncentivePlan2004Member" abstract="true" name="EquityIncentivePlan2004Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_AggregateConsiderationToRepurchaseNote" abstract="false" name="AggregateConsiderationToRepurchaseNote" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" 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_ContractAssetLiabilityAbstract" abstract="true" name="ContractAssetLiabilityAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="fivn_ShareBasedPaymentArrangementPurchaseRightsMember" abstract="true" name="ShareBasedPaymentArrangementPurchaseRightsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_CommercialCommitmentToBePaidYearOne" abstract="false" name="CommercialCommitmentToBePaidYearOne" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_Year2008Through2012Member" abstract="true" name="Year2008Through2012Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_DisputedportionMember" abstract="true" name="DisputedportionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_StockIssuedDuringPeriodValueStockOptionsandWarrantsExercised" abstract="false" name="StockIssuedDuringPeriodValueStockOptionsandWarrantsExercised" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <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_AuditInformationAbstract" abstract="true" name="AuditInformationAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="fivn_DefinedBenefitPlanRequisiteServicePeriod" abstract="false" name="DefinedBenefitPlanRequisiteServicePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="fivn_AdjustmentsToAdditionalPaidInCapitalStockIssuedDuringBusinessAcquisition" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalStockIssuedDuringBusinessAcquisition" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_DebtIssuanceCostsGrossWithinExtinguishmentOfDebt" abstract="false" name="DebtIssuanceCostsGrossWithinExtinguishmentOfDebt" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_OperatingLossCarryforwardLimitationsonUseChangeinOwnershipPeriod" abstract="false" name="OperatingLossCarryforwardLimitationsonUseChangeinOwnershipPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="fivn_DebtInstrumentConversionOfAggregatePrincipalAmountTerm1" abstract="false" name="DebtInstrumentConversionOfAggregatePrincipalAmountTerm1" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_AccrualPeriodDomain" abstract="true" name="AccrualPeriodDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_QuarterlyFinancialInformationTable" abstract="true" name="QuarterlyFinancialInformationTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <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_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedExcludingCashAndCashEquivalentsAcquiredNet" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedExcludingCashAndCashEquivalentsAcquiredNet" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_DebtInstrumentConversionMultipleOfAggregatePrincipalAmount" abstract="false" name="DebtInstrumentConversionMultipleOfAggregatePrincipalAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
