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  <xsd:element id="pmtc_Bostonleaseannualincrease" name="Bostonleaseannualincrease" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="pmtc_Bostonleasebuildingoperatingcostamountestimateyearone" name="Bostonleasebuildingoperatingcostamountestimateyearone" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="pmtc_Bostonleasebuildingoperatingcostpercent" name="Bostonleasebuildingoperatingcostpercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="pmtc_Bostonleaseleaseholdimprovementallowance" name="Bostonleaseleaseholdimprovementallowance" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="pmtc_Bostonleaseleaseholdimprovementallowancepersquarefoot" name="Bostonleaseleaseholdimprovementallowancepersquarefoot" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="pmtc_Bostonleasepersquarefootannualincrease" name="Bostonleasepersquarefootannualincrease" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="pmtc_Bostonleaseyearonepayments" name="Bostonleaseyearonepayments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="pmtc_BusinessAcquisitionNumberofEmployeesofAcquiredEntity" name="BusinessAcquisitionNumberofEmployeesofAcquiredEntity" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_BusinessCombinationContingentConsiderationLiabilities" name="BusinessCombinationContingentConsiderationLiabilities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_Businessacquisitionacquirednetassetsexcludinggoodwillintangibleassetsandcash" name="Businessacquisitionacquirednetassetsexcludinggoodwillintangibleassetsandcash" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_CADMember" name="CADMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_CapitalizedSoftwareMember" name="CapitalizedSoftwareMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_CashInvestmentLimitForAcquisitionOfBusiness" name="CashInvestmentLimitForAcquisitionOfBusiness" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="pmtc_CashProvidedForUsedInFinancingActivitiesMember" name="CashProvidedForUsedInFinancingActivitiesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_ChangesinfairvalueofcontingentconsiderationTableTextBlock" name="ChangesinfairvalueofcontingentconsiderationTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_ChineseYuanoffshoretoEuroMember" name="ChineseYuanoffshoretoEuroMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_Cloudservicesrevenuepercentoftotalrevenue" name="Cloudservicesrevenuepercentoftotalrevenue" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_CollateralizedLettersOfCreditOutstanding" name="CollateralizedLettersOfCreditOutstanding" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="pmtc_CommitmentsAndContingenciesLineItems" name="CommitmentsAndContingenciesLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_CommitmentsAndContingenciesTable" name="CommitmentsAndContingenciesTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_ComponentOfBaseRateBasisSpreadOnAdjustedLibor" name="ComponentOfBaseRateBasisSpreadOnAdjustedLibor" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_ComponentOfBaseRateBasisSpreadOnFederalFundsEffectiveRate" name="ComponentOfBaseRateBasisSpreadOnFederalFundsEffectiveRate" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_ComprehensiveIncomePolicyTextBlock" name="ComprehensiveIncomePolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_ComputerHardwareAndSoftware" name="ComputerHardwareAndSoftware" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="pmtc_ConcentrationOfCreditRiskPolicyTextBlock" name="ConcentrationOfCreditRiskPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_ContingentConsiderationLiabilityFairValueDisclosure" name="ContingentConsiderationLiabilityFairValueDisclosure" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="pmtc_CostsCapitalizedInternalDevelopmentCosts" name="CostsCapitalizedInternalDevelopmentCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="pmtc_DebtCovenantFixedChargeCoverageRatioMinimum" name="DebtCovenantFixedChargeCoverageRatioMinimum" nillable="true" substitutionGroup="xbrli:item" type="xbrli:decimalItemType" xbrli:periodType="instant" />
  <xsd:element id="pmtc_DebtInstrumentCovenantComplianceLeverageRatioFour" name="DebtInstrumentCovenantComplianceLeverageRatioFour" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="instant" />
  <xsd:element id="pmtc_DebtInstrumentCovenantComplianceLeverageRatioThree" name="DebtInstrumentCovenantComplianceLeverageRatioThree" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="instant" />
  <xsd:element id="pmtc_DebtInstrumentCovenantComplianceSeniorDebtLeverageRatio" name="DebtInstrumentCovenantComplianceSeniorDebtLeverageRatio" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="instant" />
  <xsd:element id="pmtc_DebtInstrumentCovenantComplianceSeniorDebtLeverageRatioactual" name="DebtInstrumentCovenantComplianceSeniorDebtLeverageRatioactual" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="instant" />
  <xsd:element id="pmtc_DebtInstrumentNumberofBanksinCreditFacility" name="DebtInstrumentNumberofBanksinCreditFacility" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant" />
  <xsd:element id="pmtc_Debtnetofunamortizeddebtissuancecost" name="Debtnetofunamortizeddebtissuancecost" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="pmtc_DeferredLicenseRevenueMember" name="DeferredLicenseRevenueMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_DeferredMaintenanceRevenueMember" name="DeferredMaintenanceRevenueMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_DeferredOtherServiceRevenueMember" name="DeferredOtherServiceRevenueMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_DeferredRevenuePolicyTextBlock" name="DeferredRevenuePolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_DeferredSubscriptionRevenueMember" name="DeferredSubscriptionRevenueMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_DeferredTaxAssetAmortizationOfIntangibleAssets" name="DeferredTaxAssetAmortizationOfIntangibleAssets" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="pmtc_DeferredTaxAssetDeferredInterest" name="DeferredTaxAssetDeferredInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="pmtc_DeferredTaxAssetsCapitalizedResearchAndDevelopment" name="DeferredTaxAssetsCapitalizedResearchAndDevelopment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="pmtc_DeferredTaxAssetsDepreciation" name="DeferredTaxAssetsDepreciation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="pmtc_DeferredTaxLiabilitiesAcquiredIntangibleAssets" name="DeferredTaxLiabilitiesAcquiredIntangibleAssets" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="pmtc_DeferredTaxLiabilitiesDeferredIncome" name="DeferredTaxLiabilitiesDeferredIncome" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="pmtc_DeferredTaxLiabilitiesExpectedDeferredExpense" name="DeferredTaxLiabilitiesExpectedDeferredExpense" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="pmtc_DeferredUSTaxLiabilityUnremittedForeignEarnings" name="DeferredUSTaxLiabilityUnremittedForeignEarnings" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="pmtc_DefinedBenefitPlanActualReturnOnPlanAssetsGainOrLoss" name="DefinedBenefitPlanActualReturnOnPlanAssetsGainOrLoss" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_DefinedBenefitPlanTargetAllocationPercentageOfAssetsFixedIncomeSecurities" name="DefinedBenefitPlanTargetAllocationPercentageOfAssetsFixedIncomeSecurities" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_DefinedBenefitPlansVestingPeriod" name="DefinedBenefitPlansVestingPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_DefinedContributionPlanEmployersContributionRateOfVestingPercentage" name="DefinedContributionPlanEmployersContributionRateOfVestingPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_DefinedContributionPlanMaximumPercentageOfEmployerContributionOnEmployeesEarnings" name="DefinedContributionPlanMaximumPercentageOfEmployerContributionOnEmployeesEarnings" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_DefinedContributionPlanPercentageOfEmployeesContributionsMatchedByEmployer" name="DefinedContributionPlanPercentageOfEmployeesContributionsMatchedByEmployer" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_DefinedContributionPlanVestingPeriod" name="DefinedContributionPlanVestingPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_DescriptionOfBusinessAndBasisOfPresentationAbstract" name="DescriptionOfBusinessAndBasisOfPresentationAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_DirectorsAndExecutiveOfficersMember" name="DirectorsAndExecutiveOfficersMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_DocumentAndEntityInformationAbstract" name="DocumentAndEntityInformationAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_ESPPmaximumcontributionamountbyemployee" name="ESPPmaximumcontributionamountbyemployee" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_ESPPmaximumcontributionpercentage" name="ESPPmaximumcontributionpercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="pmtc_ESPPpurchasepriceasaofstockprice" name="ESPPpurchasepriceasaofstockprice" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="pmtc_EffectiveIncomeTaxRateReconciliationChangeinPensionValuationAllowanceAmount" name="EffectiveIncomeTaxRateReconciliationChangeinPensionValuationAllowanceAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxWithholdingAmount" name="EffectiveIncomeTaxRateReconciliationForeignIncomeTaxWithholdingAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxWithholdingPercent" name="EffectiveIncomeTaxRateReconciliationForeignIncomeTaxWithholdingPercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_EffectiveIncomeTaxRateReconciliationPermanentDomesticItemsAmount" name="EffectiveIncomeTaxRateReconciliationPermanentDomesticItemsAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_EffectiveIncomeTaxRateReconciliationPermanentDomesticItemsPercent" name="EffectiveIncomeTaxRateReconciliationPermanentDomesticItemsPercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_EffectiveIncomeTaxRateReconciliationPermanentDomesticItemsRelatedToPendingLegalSettlementAmount" name="EffectiveIncomeTaxRateReconciliationPermanentDomesticItemsRelatedToPendingLegalSettlementAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_EffectiveIncomeTaxRateReconciliationResolutionofUncertainTaxPositionsAmount" name="EffectiveIncomeTaxRateReconciliationResolutionofUncertainTaxPositionsAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_EffectiveIncomeTaxRateReconciliationResolutionofUncertainTaxPositionsPercent" name="EffectiveIncomeTaxRateReconciliationResolutionofUncertainTaxPositionsPercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_EmployeeSeveranceAndRelatedBenefitsMember" name="EmployeeSeveranceAndRelatedBenefitsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_Estimatedforfeitureadjustment" name="Estimatedforfeitureadjustment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="pmtc_EuropeCorporateInvestmentGradeMember" name="EuropeCorporateInvestmentGradeMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_EuropeLargeCapitalizationStocksMember" name="EuropeLargeCapitalizationStocksMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_ExtendedPLMMember" name="ExtendedPLMMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_FairValueOfPlanAssetsLineItems" name="FairValueOfPlanAssetsLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_FairValueOfPlanAssetsTable" name="FairValueOfPlanAssetsTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_FixedChargeCoverageRatioActual" name="FixedChargeCoverageRatioActual" nillable="true" substitutionGroup="xbrli:item" type="xbrli:decimalItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="pmtc_ForeignjurisdictionMember" name="ForeignjurisdictionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_GeographicalSegmentsMember" name="GeographicalSegmentsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_GoodwillAndAcquiredIntangibleAssetsByReportableSegment" name="GoodwillAndAcquiredIntangibleAssetsByReportableSegment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="pmtc_GrossDeferredAmortizationCarryforward" name="GrossDeferredAmortizationCarryforward" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="pmtc_GrossDeferredInterestCarryforward" name="GrossDeferredInterestCarryforward" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="pmtc_IncomeTaxDisclosureLineItems" name="IncomeTaxDisclosureLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_IncomeTaxDisclosureTable" name="IncomeTaxDisclosureTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_IncreaseDecreaseofValuationAllowanceEstablishmentinForeignJurisdictions" name="IncreaseDecreaseofValuationAllowanceEstablishmentinForeignJurisdictions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_InsuranceCompanyFundsMember" name="InsuranceCompanyFundsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_InsuranceCompanyMember" name="InsuranceCompanyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_InternationalPlanAssetsMember" name="InternationalPlanAssetsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_InvestmentInForeignSubsidiariesAuthorizedAmount" name="InvestmentInForeignSubsidiariesAuthorizedAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="pmtc_IoTGroupMember" name="IoTGroupMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_IoTSegmentMember" name="IoTSegmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_JapaneseYentoEuroMember" name="JapaneseYentoEuroMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_LandlordReimbursements" name="LandlordReimbursements" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_LeverageRatioActual" name="LeverageRatioActual" nillable="true" substitutionGroup="xbrli:item" type="xbrli:decimalItemType" xbrli:periodType="instant" />
  <xsd:element id="pmtc_LicenseandSubscriptionCost" name="LicenseandSubscriptionCost" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_LicenseandSubscriptionCostMember" name="LicenseandSubscriptionCostMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_LineOfCreditFacilityVariableInterestRateLengthOfTimeBetweenUpdates" name="LineOfCreditFacilityVariableInterestRateLengthOfTimeBetweenUpdates" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_LongTermRateOfReturnOnAssets" name="LongTermRateOfReturnOnAssets" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_MaintenanceCostsMember" name="MaintenanceCostsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_MaximumTermOfCreditToCustomers" name="MaximumTermOfCreditToCustomers" nillable="true" substitutionGroup="xbrli:item" type="xbrli:positiveIntegerItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_Netoperatinglossrelatedtowindfalltaxdeductions" name="Netoperatinglossrelatedtowindfalltaxdeductions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="pmtc_NotionalamountofforeigncurrencyderivativecontractAbstract" name="NotionalamountofforeigncurrencyderivativecontractAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_NumberOfEmployeesTerminated" name="NumberOfEmployeesTerminated" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_NumberOfEqualAnnualInstallments" name="NumberOfEqualAnnualInstallments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_NumberofCostofRevenueCategories" name="NumberofCostofRevenueCategories" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_NumberofProductAreas" name="NumberofProductAreas" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_OperatingLeaseAdditionalTerm" name="OperatingLeaseAdditionalTerm" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_OperatingLeaseUtilitiesCost" name="OperatingLeaseUtilitiesCost" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_OperatingLeasesRentExpenseAnnual" name="OperatingLeasesRentExpenseAnnual" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_OtherComprehensiveIncomeLossPensionandOtherPostretirementBenefitPlansForeignCurrencyTranslationGainLossArisingDuringPeriodNetofTax" name="OtherComprehensiveIncomeLossPensionandOtherPostretirementBenefitPlansForeignCurrencyTranslationGainLossArisingDuringPeriodNetofTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_OtherComprehensiveIncomeLossPensionandOtherPostretirementBenefitPlansNetUnamortizedGainLossOccurringDuringPeriodBeforeTax" name="OtherComprehensiveIncomeLossPensionandOtherPostretirementBenefitPlansNetUnamortizedGainLossOccurringDuringPeriodBeforeTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_OtherComprehensiveIncomeLossPensionandOtherPostretirementBenefitPlansNetUnamortizedGainLossRecognizedDuringPeriodBeforeTax" name="OtherComprehensiveIncomeLossPensionandOtherPostretirementBenefitPlansNetUnamortizedGainLossRecognizedDuringPeriodBeforeTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_OtherComprehensiveIncomeLossPensionandOtherPostretirementBenefitPlansNetUnamortizedGainLossofForeignCurrencyArisingDuringPeriodNetofTax" name="OtherComprehensiveIncomeLossPensionandOtherPostretirementBenefitPlansNetUnamortizedGainLossofForeignCurrencyArisingDuringPeriodNetofTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_OtherComprehensiveIncomeLossPensionandOtherPostretirementBenefitPlansSettlementLossOccurringDuringPeriodBeforeTax" name="OtherComprehensiveIncomeLossPensionandOtherPostretirementBenefitPlansSettlementLossOccurringDuringPeriodBeforeTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_OtherEmployeesMember" name="OtherEmployeesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_OtherInternationalMember" name="OtherInternationalMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_OutofPeriodCorrectionMember" name="OutofPeriodCorrectionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_Paymentofcontingentconsideration" name="Paymentofcontingentconsideration" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_PaymentstoBusinessCombinationContingentConsiderationFinancingActivities" name="PaymentstoBusinessCombinationContingentConsiderationFinancingActivities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_PerformanceBasedAwardMember" name="PerformanceBasedAwardMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_Perpetuallicenserevenue" name="Perpetuallicenserevenue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_PreVestingForfeitureRate" name="PreVestingForfeitureRate" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_ProceedsFromSaleOfCostMethodInvestments" name="ProceedsFromSaleOfCostMethodInvestments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_ProductsAndServicesSegmentsMember" name="ProductsAndServicesSegmentsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_ProfessionalServicesMember" name="ProfessionalServicesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_RDcreditrelatedtowindfalltaxdeductions" name="RDcreditrelatedtowindfalltaxdeductions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="pmtc_RealignmentMember" name="RealignmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_RestrictedSharesAndRestrictedStockUnitsMember" name="RestrictedSharesAndRestrictedStockUnitsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_RestrictedStockValueSharesNettedForTaxWithHoldings" name="RestrictedStockValueSharesNettedForTaxWithHoldings" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_RestructuringAbstract" name="RestructuringAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_RestructuringPlan2015Member" name="RestructuringPlan2015Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_RestructuringPlan2016Member" name="RestructuringPlan2016Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_RevolvingLoanResetPeriodOneMember" name="RevolvingLoanResetPeriodOneMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_SLMMember" name="SLMMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_SavingsPlanMember" name="SavingsPlanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_ScheduleOfAmortizationOfFiniteLivedIntangibleAssetsTableTextBlock" name="ScheduleOfAmortizationOfFiniteLivedIntangibleAssetsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardAwardCategoryAxis" name="ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardAwardCategoryAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardAwardCategoryDomain" name="ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardAwardCategoryDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_SegmentServicesMember" name="SegmentServicesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_SegmentSoftwareProductsMember" name="SegmentSoftwareProductsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsCommonStockIssuablePerRestrictedStockUnit" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsCommonStockIssuablePerRestrictedStockUnit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:decimalItemType" xbrli:periodType="instant" />
  <xsd:element id="pmtc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalFairValueOfRestrictedStockAndRestrictedStockUnitAwardsVested" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalFairValueOfRestrictedStockAndRestrictedStockUnitAwardsVested" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_SharebasedCompensationArrangementbySharebasedPaymentAwardTargetMultiplier" name="SharebasedCompensationArrangementbySharebasedPaymentAwardTargetMultiplier" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_SharesReservedForIssuanceUponExerciseOfStockOptionsAndRestrictedStockUnitsGrantedAndOutstanding" name="SharesReservedForIssuanceUponExerciseOfStockOptionsAndRestrictedStockUnitsGrantedAndOutstanding" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element id="pmtc_SharesRetainedByCompanyToCoverTaxWithholdingsUponVestingOfStockBasedAwards" name="SharesRetainedByCompanyToCoverTaxWithholdingsUponVestingOfStockBasedAwards" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_SharesSurrenderedByEmployeesToPayTaxesRelatedToStockBasedAwardsShares" name="SharesSurrenderedByEmployeesToPayTaxesRelatedToStockBasedAwardsShares" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_SharesSurrenderedByEmployeesToPayTaxesRelatedToStockBasedAwardsValue" name="SharesSurrenderedByEmployeesToPayTaxesRelatedToStockBasedAwardsValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_SolutionsGroupMember" name="SolutionsGroupMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_StatementofCashFlowsAxis" name="StatementofCashFlowsAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_StatementofCashFlowsDomain" name="StatementofCashFlowsDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_StockmodificationAxis" name="StockmodificationAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_StockmodificationDomain" name="StockmodificationDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_StockmodificationMember" name="StockmodificationMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_SubleaseincomeMember" name="SubleaseincomeMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_SubscriptionRevenueNumberofPrimarySources" name="SubscriptionRevenueNumberofPrimarySources" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_SubscriptionSupportandLicenseCost" name="SubscriptionSupportandLicenseCost" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_SubscriptionSupportandLicenseRevenue" name="SubscriptionSupportandLicenseRevenue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_SummaryOfSignificantAccountingPoliciesLineItems" name="SummaryOfSignificantAccountingPoliciesLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_SummaryOfSignificantAccountingPoliciesTable" name="SummaryOfSignificantAccountingPoliciesTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_SwissFranctoEuroMember" name="SwissFranctoEuroMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_TSRUnitsMember" name="TSRUnitsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_TechnologyServicesCostsMember" name="TechnologyServicesCostsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_TimeBasedAwardMember" name="TimeBasedAwardMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_TotalRecurringRevenue" name="TotalRecurringRevenue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_TotalSegmentsMember" name="TotalSegmentsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_UnallocatedOperatingExpennses" name="UnallocatedOperatingExpennses" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_UnrecognizedTaxBenefitsChangesRelatedtoCurrentYearPositionsAbstract" name="UnrecognizedTaxBenefitsChangesRelatedtoCurrentYearPositionsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_UnrecognizedTaxBenefitsChangesRelatedtoPriorYearPositionsAbstract" name="UnrecognizedTaxBenefitsChangesRelatedtoPriorYearPositionsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_UnrecognizedTaxBenefitsIncreaseInValuationAllowanceUponRecognition" name="UnrecognizedTaxBenefitsIncreaseInValuationAllowanceUponRecognition" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="pmtc_ValuationAllowanceEstablishmentInForeignJurisdictions" name="ValuationAllowanceEstablishmentInForeignJurisdictions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_ValuationAllowanceNetIncreaseInDeferredTaxAssetsForForeignJurisdictionsWithFullValuationAllowance" name="ValuationAllowanceNetIncreaseInDeferredTaxAssetsForForeignJurisdictionsWithFullValuationAllowance" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_ValuationAllowanceReleaseOfValuationAllowance" name="ValuationAllowanceReleaseOfValuationAllowance" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="pmtc_VotingInterestInForeignSubsidiariesPledgedAgainstCreditFacility" name="VotingInterestInForeignSubsidiariesPledgedAgainstCreditFacility" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_Votinginterestindomesticsubsidiariespledgedagainstcreditfacility" name="Votinginterestindomesticsubsidiariespledgedagainstcreditfacility" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_VuforiaAcquisitionMember" name="VuforiaAcquisitionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="pmtc_WindfallTaxBenefitMember" name="WindfallTaxBenefitMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="pmtc_WindfallTaxDeductionsNotYetRecognized" name="WindfallTaxDeductionsNotYetRecognized" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
</xsd:schema>
