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  <xs:element id="ftnt_EffectiveIncomeTaxRateReconciliationCanadianDeemedDividendDistribution" abstract="false" name="EffectiveIncomeTaxRateReconciliationCanadianDeemedDividendDistribution" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ftnt_OperatingLeaseRemainingLeaseTerm" abstract="false" name="OperatingLeaseRemainingLeaseTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ftnt_MutualCovenantNottoSueAgreementPatentClaimsAllocatedValue" abstract="false" name="MutualCovenantNottoSueAgreementPatentClaimsAllocatedValue" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ftnt_InvestmentsClassificationAsLongTermMinimumMaturity" abstract="false" name="InvestmentsClassificationAsLongTermMinimumMaturity" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ftnt_IncomeTaxLiabilitiesNoncurrentMember" abstract="true" name="IncomeTaxLiabilitiesNoncurrentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ftnt_StockIssuedDuringPeriodValueEquityIncentivePlansNetofTaxesWithheld" abstract="false" name="StockIssuedDuringPeriodValueEquityIncentivePlansNetofTaxesWithheld" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ftnt_FinancialInstrumentsAndFairValueAbstract" abstract="true" name="FinancialInstrumentsAndFairValueAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ftnt_SharebasedCompensationArrangementbySharebasedPaymentAwardNumberofPrimaryStockIncentivePlans" abstract="false" name="SharebasedCompensationArrangementbySharebasedPaymentAwardNumberofPrimaryStockIncentivePlans" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ftnt_PurchaseObligationToBePaidAfterYearTwo" abstract="false" name="PurchaseObligationToBePaidAfterYearTwo" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
