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				<link:definition>006070 - Disclosure - Inventory</link:definition>
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				<link:definition>006170 - Disclosure - Income Taxes</link:definition>
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	<xs:element name="NumberOfNewBuildingsLeased" id="regn_NumberOfNewBuildingsLeased" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="CashAndMarketableDebtSecuritiesCollateral" id="regn_CashAndMarketableDebtSecuritiesCollateral" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
	<xs:element name="RentalChargesForUtilitiesRealEstateTaxesAndOperatingExpense" id="regn_RentalChargesForUtilitiesRealEstateTaxesAndOperatingExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="ImputedInterestRateApplicableToFacilityLeaseObligation" id="regn_ImputedInterestRateApplicableToFacilityLeaseObligation" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="FacilityLeaseObligation" id="regn_FacilityLeaseObligation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant"/>
	<xs:element name="RoyaltyRateMaximum" id="regn_RoyaltyRateMaximum" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="RoyaltyRateMinimum" id="regn_RoyaltyRateMinimum" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="TerminationNoticeMinimum" id="regn_TerminationNoticeMinimum" type="us-types:durationStringItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="TerminationNoticeMaximum" id="regn_TerminationNoticeMaximum" type="us-types:durationStringItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="NonRefundableAdvancePaymentMadeUnderLicenseAgreement" id="regn_NonRefundableAdvancePaymentMadeUnderLicenseAgreement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="AmortizationOfAdvancePayment" id="regn_AmortizationOfAdvancePayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="UnamortizedBalanceOfAdvancePayment" id="regn_UnamortizedBalanceOfAdvancePayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
	<xs:element name="FacilityLeasesFutureMinimumPaymentsDueAbstract" id="regn_FacilityLeasesFutureMinimumPaymentsDueAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="FacilityLeasesFutureMinimumPaymentsDueCurrent" id="regn_FacilityLeasesFutureMinimumPaymentsDueCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant"/>
	<xs:element name="FacilityLeasesFutureMinimumPaymentsDueDueInTwoYears" id="regn_FacilityLeasesFutureMinimumPaymentsDueDueInTwoYears" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant"/>
	<xs:element name="FacilityLeasesFutureMinimumPaymentsDueDueInThreeYears" id="regn_FacilityLeasesFutureMinimumPaymentsDueDueInThreeYears" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant"/>
	<xs:element name="FacilityLeasesFutureMinimumPaymentsDueDueInFourYears" id="regn_FacilityLeasesFutureMinimumPaymentsDueDueInFourYears" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant"/>
	<xs:element name="FacilityLeasesFutureMinimumPaymentsDueDueInFiveYears" id="regn_FacilityLeasesFutureMinimumPaymentsDueDueInFiveYears" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant"/>
	<xs:element name="FacilityLeasesFutureMinimumPaymentsDueDueThereafter" id="regn_FacilityLeasesFutureMinimumPaymentsDueDueThereafter" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant"/>
	<xs:element name="FacilityLeasesFutureMinimumPaymentsDue" id="regn_FacilityLeasesFutureMinimumPaymentsDue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant"/>
	<xs:element name="CommitmentsUnderFacilityLeaseObligationsTableTextBlock" id="regn_CommitmentsUnderFacilityLeaseObligationsTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="MarketableDebtSecuritiesCollateral" id="regn_MarketableDebtSecuritiesCollateral" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
	<xs:element name="FacilityLeaseObligationsAbstract" id="regn_FacilityLeaseObligationsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="ReimbursementsRecognizedAsAdditionalFacilityLeaseObligation" id="regn_ReimbursementsRecognizedAsAdditionalFacilityLeaseObligation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="InterestExpenseInConnectionWithFacilityLeaseObligation" id="regn_InterestExpenseInConnectionWithFacilityLeaseObligation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="FacilityLeaseObligationIncludingReimbursements" id="regn_FacilityLeaseObligationIncludingReimbursements" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant"/>
	<xs:element name="ResearchCollaborationAndLicensingAgreementsAbstract" id="regn_ResearchCollaborationAndLicensingAgreementsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="FutureAmortizationExpenseOfAdvancePaymentAbstract" id="regn_FutureAmortizationExpenseOfAdvancePaymentAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="FutureExpenseOfAdvancePaymentYearOne" id="regn_FutureExpenseOfAdvancePaymentYearOne" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="FutureExpenseOfAdvancePaymentYearTwo" id="regn_FutureExpenseOfAdvancePaymentYearTwo" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="FutureExpenseOfAdvancePaymentYearThree" id="regn_FutureExpenseOfAdvancePaymentYearThree" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="FutureExpenseOfAdvancePaymentYearFour" id="regn_FutureExpenseOfAdvancePaymentYearFour" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="FutureExpenseOfAdvancePaymentYearFive" id="regn_FutureExpenseOfAdvancePaymentYearFive" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="DescriptionOfPeriodOfStandstillProvisions" id="regn_DescriptionOfPeriodOfStandstillProvisions" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="MaximumPercentageOfOutstandingSharesThatMayBeAcquiredUnderStandstillProvisions" id="regn_MaximumPercentageOfOutstandingSharesThatMayBeAcquiredUnderStandstillProvisions" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
	<xs:element name="VolumeLimitationOfSalesOfCommonStock" id="regn_VolumeLimitationOfSalesOfCommonStock" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="PercentageOfOutstandingSharesOrVotingRightsUnderAmendedInvestorAgreement" id="regn_PercentageOfOutstandingSharesOrVotingRightsUnderAmendedInvestorAgreement" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
	<xs:element name="NumberOfNewlyIssuedUnregisteredSharesOfCommonStockPurchased" id="regn_NumberOfNewlyIssuedUnregisteredSharesOfCommonStockPurchased" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="CashPriceOfNewlyIssuedUnregisteredSharesOfCommonStockPurchased" id="regn_CashPriceOfNewlyIssuedUnregisteredSharesOfCommonStockPurchased" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration"/>
	<xs:element name="DeferredTaxAssetsDeferredExpenseCapitalizedResearchAndDevelopmentCosts" id="regn_DeferredTaxAssetsDeferredExpenseCapitalizedResearchAndDevelopmentCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
	<xs:element name="DeferredTaxAssetsPropertyPlantAndEquipment" id="regn_DeferredTaxAssetsPropertyPlantAndEquipment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
	<xs:element name="NetOperatingLossCarryForwardsExercisesOfNonqualifiedStockOptionsAndDisqualifyingDispositionsOfIncentiveStockOptions" id="regn_NetOperatingLossCarryForwardsExercisesOfNonqualifiedStockOptionsAndDisqualifyingDispositionsOfIncentiveStockOptions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
	<xs:element name="IncomeTaxExpenseBenefitResultingFromProvisionInHousingAssistanceTaxActOf2008" id="regn_IncomeTaxExpenseBenefitResultingFromProvisionInHousingAssistanceTaxActOf2008" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="IncomeTaxExpenseBenefitResultingFromProvisionInWorkerHomeownershipAndBusinessAssistanceActOf2009" id="regn_IncomeTaxExpenseBenefitResultingFromProvisionInWorkerHomeownershipAndBusinessAssistanceActOf2009" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="IncomeTaxExpenseBenefitResultingFromProvisionInAmericanRecoveryAndReinvestmentActOf2009" id="regn_IncomeTaxExpenseBenefitResultingFromProvisionInAmericanRecoveryAndReinvestmentActOf2009" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="ResearchAndDevelopmentCostsCapitalized" id="regn_ResearchAndDevelopmentCostsCapitalized" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="CapitalizedResearchAndDevelopmentCostsAmortizationPeriod" id="regn_CapitalizedResearchAndDevelopmentCostsAmortizationPeriod" type="us-types:durationStringItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonvestedNumber" id="regn_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonvestedNumber" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
	<xs:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpectedToVestUponAchievingSalesTargets" id="regn_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpectedToVestUponAchievingSalesTargets" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
	<xs:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpectedToVestUponAchievingDevelopmentMilestones" id="regn_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpectedToVestUponAchievingDevelopmentMilestones" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
	<xs:element name="EmployeeServiceShareBasedCompensationNonvestedOptionsPotentialCompensationCost" id="regn_EmployeeServiceShareBasedCompensationNonvestedOptionsPotentialCompensationCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
	<xs:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePricesAndWeightedAverageGrantDateFairValueTableTextBlock" id="regn_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePricesAndWeightedAverageGrantDateFairValueTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardExpiration" id="regn_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardExpiration" type="us-types:durationStringItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="ExercisePriceEqualToMarketPriceAbstract" id="regn_ExercisePriceEqualToMarketPriceAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="EstimatedPercentageOfOptionsIssuedThatWillVest" id="regn_EstimatedPercentageOfOptionsIssuedThatWillVest" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="AmountOfNonRefundablePaymentReceivedForCollaborationAgreement" id="regn_AmountOfNonRefundablePaymentReceivedForCollaborationAgreement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="RoyaltyBasedOnPercentageOfAnnualSalesInJapan" id="regn_RoyaltyBasedOnPercentageOfAnnualSalesInJapan" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="PercentageOfDevelopmentExpensesToBeReimbursedDueToProfitabilityOfCollaborationAgreement" id="regn_PercentageOfDevelopmentExpensesToBeReimbursedDueToProfitabilityOfCollaborationAgreement" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="NumberOfYearsOfFirstCommercialSaleUnderCollaborationAgreement" id="regn_NumberOfYearsOfFirstCommercialSaleUnderCollaborationAgreement" type="us-types:durationStringItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="ReimbursementOfDevelopmentExpensesInAccordanceWithFormulaUntilFirstCommercialSale" id="regn_ReimbursementOfDevelopmentExpensesInAccordanceWithFormulaUntilFirstCommercialSale" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="ExcessShareOfProfitNotRequiredToToBeAppliedToReimburseDevelopmentCost" id="regn_ExcessShareOfProfitNotRequiredToToBeAppliedToReimburseDevelopmentCost" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="AmountOfFundingOfAgreedUponCostIncurredToExpandManufacturingCapacity" id="regn_AmountOfFundingOfAgreedUponCostIncurredToExpandManufacturingCapacity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration"/>
	<xs:element name="MinimumAmountOfResearchFunding" id="regn_MinimumAmountOfResearchFunding" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="AdditionalFundingToOptimizeCertainExistingTechnology" id="regn_AdditionalFundingToOptimizeCertainExistingTechnology" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="DevelopmentExpensesIncurredToDate" id="regn_DevelopmentExpensesIncurredToDate" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
	<xs:element name="MinimumAdvanceNoticeRequiredToTerminateCollaborationAgreement" id="regn_MinimumAdvanceNoticeRequiredToTerminateCollaborationAgreement" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="IncreaseDecreaseInCollaborationRevenueRecognizedBasedOnShortenedExtendedPerformancePeriod" id="regn_IncreaseDecreaseInCollaborationRevenueRecognizedBasedOnShortenedExtendedPerformancePeriod" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration"/>
	<xs:element name="AmountOfResearchFundedFromInceptionToDate" id="regn_AmountOfResearchFundedFromInceptionToDate" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
	<xs:element name="AnnualFundingMaximumOfResearchActivitiesPerAmendedAgreement" id="regn_AnnualFundingMaximumOfResearchActivitiesPerAmendedAgreement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
	<xs:element name="AdjustedMaximumAmountOfAnnualFundingPerAmendedAgreement" id="regn_AdjustedMaximumAmountOfAnnualFundingPerAmendedAgreement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
	<xs:element name="AmountOfResearchFundedDuringPeriod" id="regn_AmountOfResearchFundedDuringPeriod" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="BalanceBetweenAmountFundedAndAnnualFundingMaximum" id="regn_BalanceBetweenAmountFundedAndAnnualFundingMaximum" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
	<xs:element name="OptionToExtend" id="regn_OptionToExtend" type="us-types:durationStringItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="NumberOfTherapeuticAntibodiesCurrentlyUnderDevelopment" id="regn_NumberOfTherapeuticAntibodiesCurrentlyUnderDevelopment" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
	<xs:element name="PercentageOfTrialCostsBorneByCollaboratingParty" id="regn_PercentageOfTrialCostsBorneByCollaboratingParty" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="PercentageOfTrialCostsBorneByEntity" id="regn_PercentageOfTrialCostsBorneByEntity" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="PercentageOfTrialCostsToBeReimbursedDueToProfitabilityOfAgreement" id="regn_PercentageOfTrialCostsToBeReimbursedDueToProfitabilityOfAgreement" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="StartingShareOfProfitsOutsideUnitedStatesBasedOnSalesForCollaboratingParty" id="regn_StartingShareOfProfitsOutsideUnitedStatesBasedOnSalesForCollaboratingParty" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="StartingShareOfProfitsOutsideUnitedStatesBasedOnSalesForCompany" id="regn_StartingShareOfProfitsOutsideUnitedStatesBasedOnSalesForCompany" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="EndingShareOfProfitsOutsideUnitedStatesBasedOnSalesForCollaboratingParty" id="regn_EndingShareOfProfitsOutsideUnitedStatesBasedOnSalesForCollaboratingParty" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="EndingShareOfProfitsOutsideUnitedStatesBasedOnSalesForCompany" id="regn_EndingShareOfProfitsOutsideUnitedStatesBasedOnSalesForCompany" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="ShareOfLossesOutsideUnitedStatesForCollaboratingParty" id="regn_ShareOfLossesOutsideUnitedStatesForCollaboratingParty" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="ShareOfLossesOutsideUnitedStatesForCompany" id="regn_ShareOfLossesOutsideUnitedStatesForCompany" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="PeriodOfNoticeToOptOutOfFurtherDevelopmentAndOrCommercialization" id="regn_PeriodOfNoticeToOptOutOfFurtherDevelopmentAndOrCommercialization" type="us-types:durationStringItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="PeriodOfNoticeToOptOutOfFurtherDevelopmentUponEnteringOfJointDevelopmentProduct" id="regn_PeriodOfNoticeToOptOutOfFurtherDevelopmentUponEnteringOfJointDevelopmentProduct" type="us-types:durationStringItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="MinimumPaymentsExpectedToBeReceivedUnderAgreement" id="regn_MinimumPaymentsExpectedToBeReceivedUnderAgreement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
	<xs:element name="AmountOfMilestonePaymentsEarned" id="regn_AmountOfMilestonePaymentsEarned" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration"/>
	<xs:element name="MaximumAmountOfSalesMilestonePaymentsIfTotalSalesAchieveSpecificLevels" id="regn_MaximumAmountOfSalesMilestonePaymentsIfTotalSalesAchieveSpecificLevels" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="DevelopmentExpensesThatWereSharedEqually" id="regn_DevelopmentExpensesThatWereSharedEqually" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="DevelopmentExpensesForWhichCompanyWasSolelyResponsible" id="regn_DevelopmentExpensesForWhichCompanyWasSolelyResponsible" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="AdditionalResearchAndDevelopmentExpensesObligatedToReimburse" id="regn_AdditionalResearchAndDevelopmentExpensesObligatedToReimburse" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="MilestonePaymentReceivable" id="regn_MilestonePaymentReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
	<xs:element name="ConditionsForCommencementOfSalesMilestonePayments" id="regn_ConditionsForCommencementOfSalesMilestonePayments" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="AmountOfFundingToExpandManufacturingCapacityThatHasBeenReceivedOrIsReceivable" id="regn_AmountOfFundingToExpandManufacturingCapacityThatHasBeenReceivedOrIsReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
	<xs:element name="NumberOfSubstantiveMilestonePaymentsEarned" id="regn_NumberOfSubstantiveMilestonePaymentsEarned" type="xbrli:integerItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="FuturePaymentToBeMadeUnderTermsOfAmendedLicensingAgreement" id="regn_FuturePaymentToBeMadeUnderTermsOfAmendedLicensingAgreement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
	<xs:element name="FinishedGoodsHeldAtDistributorsSpecialPharmacies" id="regn_FinishedGoodsHeldAtDistributorsSpecialPharmacies" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
	<xs:element name="DepreciationAndAmortizationLessAmountsCapitalized" id="regn_DepreciationAndAmortizationLessAmountsCapitalized" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="DebtInstrumentConvertibleFairValueOfLiabilityComponent" id="regn_DebtInstrumentConvertibleFairValueOfLiabilityComponent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant"/>
	<xs:element name="NetCostOfConvertibleNoteHedgeAndWarrantTransactions" id="regn_NetCostOfConvertibleNoteHedgeAndWarrantTransactions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="StockIssuedDuringPeriodValueStockOptionsExercisedNetOfSharesTendered" id="regn_StockIssuedDuringPeriodValueStockOptionsExercisedNetOfSharesTendered" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration"/>
	<xs:element name="StockIssuedDuringPeriodSharesStockOptionsExercisedNetOfSharesTendered" id="regn_StockIssuedDuringPeriodSharesStockOptionsExercisedNetOfSharesTendered" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="AmountOfPaymentToBeMadeUponReachingMinimumSalesTarget" id="regn_AmountOfPaymentToBeMadeUponReachingMinimumSalesTarget" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
	<xs:element name="CumulativeSalesRangeMinimum" id="regn_CumulativeSalesRangeMinimum" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration"/>
	<xs:element name="RoyaltyPaymentPercentageOfCumulativeSalesWithinRange" id="regn_RoyaltyPaymentPercentageOfCumulativeSalesWithinRange" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="CumulativeSalesRangeMaximum" id="regn_CumulativeSalesRangeMaximum" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration"/>
	<xs:element name="RoyaltyPaymentPercentageOfCumulativeSalesOverRange" id="regn_RoyaltyPaymentPercentageOfCumulativeSalesOverRange" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="MaximumAmountOfMilestonePaymentsThatMayBeReceivedIfCertainSalesAreAchieved" id="regn_MaximumAmountOfMilestonePaymentsThatMayBeReceivedIfCertainSalesAreAchieved" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="NumberOfOptionsThatVestedUponAttainmentOfPerformanceConditions" id="regn_NumberOfOptionsThatVestedUponAttainmentOfPerformanceConditions" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="NonCashStockBasedCompensationExpenseRecognizedForOptionsVestedUponAttainmentOfPerformanceConditions" id="regn_NonCashStockBasedCompensationExpenseRecognizedForOptionsVestedUponAttainmentOfPerformanceConditions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="NetDeferredTaxAssetsLiabilitiesGross" id="regn_NetDeferredTaxAssetsLiabilitiesGross" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
	<xs:element name="NetCarryingAmountOfLiabilityComponentAbstract" id="regn_NetCarryingAmountOfLiabilityComponentAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="InterestExpenseAssociatedWithConvertibleNotesTableTextBlock" id="regn_InterestExpenseAssociatedWithConvertibleNotesTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="FurnitureComputerAndOfficeEquipmentAndOtherMember" id="regn_FurnitureComputerAndOfficeEquipmentAndOtherMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="NewLaboratoryAndOfficeFacilitiesMember" id="regn_NewLaboratoryAndOfficeFacilitiesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="CollaborationAgreementWithBayerHealthcareLlcMember" id="regn_CollaborationAgreementWithBayerHealthcareLlcMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="GrantFromNationalInstitutesOfHealthMember" id="regn_GrantFromNationalInstitutesOfHealthMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="CollaborationAgreementWithSanofiMember" id="regn_CollaborationAgreementWithSanofiMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="AfliberceptAgreementMember" id="regn_AfliberceptAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="AntibodyCollaborationMember" id="regn_AntibodyCollaborationMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="VelocigeneAgreementMember" id="regn_VelocigeneAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="ResearchAndDevelopmentArrangementContractToPerformForOthersByProductAxis" id="regn_ResearchAndDevelopmentArrangementContractToPerformForOthersByProductAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="ResearchAndDevelopmentArrangementContractToPerformForOthersByProductDomain" id="regn_ResearchAndDevelopmentArrangementContractToPerformForOthersByProductDomain" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="OtherDeferredRevenueAgreementsMember" id="regn_OtherDeferredRevenueAgreementsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="LicenseAgreementWithAstellasPharmaIncMember" id="regn_LicenseAgreementWithAstellasPharmaIncMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="LicenseAgreementWithAstrazenecaUkLimitedMember" id="regn_LicenseAgreementWithAstrazenecaUkLimitedMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="EyleaNetProductSalesMember" id="regn_EyleaNetProductSalesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="GrossProductRevenueMember" id="regn_GrossProductRevenueMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="TotalRevenueMember" id="regn_TotalRevenueMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="USGovernmentGuaranteedCorporateBondsMember" id="regn_USGovernmentGuaranteedCorporateBondsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="UnrestrictedMember" id="regn_UnrestrictedMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="RestrictedMember" id="regn_RestrictedMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="ClassificationOfInvestmentAxis" id="regn_ClassificationOfInvestmentAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="ClassificationOfInvestmentDomain" id="regn_ClassificationOfInvestmentDomain" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="WarrantTransactionsMember" id="regn_WarrantTransactionsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="TarrytownLeaseMember" id="regn_TarrytownLeaseMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="NameOfLeaseAxis" id="regn_NameOfLeaseAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="NameOfLeaseDomain" id="regn_NameOfLeaseDomain" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="FacilitiesBuildingsAndBMember" id="regn_FacilitiesBuildingsAndBMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="FacilitiesBuildingCMember" id="regn_FacilitiesBuildingCMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="ScheduleOfFacilityLeasesTable" id="regn_ScheduleOfFacilityLeasesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="FacilityLeaseObligationsAxis" id="regn_FacilityLeaseObligationsAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="FacilityLeaseObligationsNameDomain" id="regn_FacilityLeaseObligationsNameDomain" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="ScheduleOfFacilityLeasesLineItems" id="regn_ScheduleOfFacilityLeasesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="AgreementsWithRoyaltyProvisionsMember" id="regn_AgreementsWithRoyaltyProvisionsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="AgreementsWithFeeProvisionsMember" id="regn_AgreementsWithFeeProvisionsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="LicensingAgreementsWhichRequireRoyaltyPaymentsBasedOnArcalystNetProductSalesMember" id="regn_LicensingAgreementsWhichRequireRoyaltyPaymentsBasedOnArcalystNetProductSalesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="CellectisAgreementMember" id="regn_CellectisAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="LicenseAgreementWithGenentechMember" id="regn_LicenseAgreementWithGenentechMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="ResearchCollaborationAndLicensingArrangementsTable" id="regn_ResearchCollaborationAndLicensingArrangementsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="ResearchCollaborationAndLicensingAgreementsAxis" id="regn_ResearchCollaborationAndLicensingAgreementsAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="ResearchCollaborationAndLicensingAgreementsDomain" id="regn_ResearchCollaborationAndLicensingAgreementsDomain" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="ResearchCollaborationAndLicensingArrangementsLineItems" id="regn_ResearchCollaborationAndLicensingArrangementsLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="SanofiMember" id="regn_SanofiMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="PhantomStockMember" id="regn_PhantomStockMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="NonPerformanceBasedStockOptionsMember" id="regn_NonPerformanceBasedStockOptionsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="PerformanceBasedStockOptionsMember" id="regn_PerformanceBasedStockOptionsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="IncentivePlan1990Member" id="regn_IncentivePlan1990Member" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="LongTermIncentivePlan2000Member" id="regn_LongTermIncentivePlan2000Member" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="ExecutiveStockPurchasePlanMember" id="regn_ExecutiveStockPurchasePlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="NetOperatingLossCarryforwardAndTaxCreditCarryforwardsMember" id="regn_NetOperatingLossCarryforwardAndTaxCreditCarryforwardsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="NetOperatingLossCarryforwardMember" id="regn_NetOperatingLossCarryforwardMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="USFederalAndNewYorkStateMember" id="regn_USFederalAndNewYorkStateMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="DocumentAndEntityInformationAbstract" id="regn_DocumentAndEntityInformationAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="PercentageOfPromptPayDiscountCompayAccrues" id="regn_PercentageOfPromptPayDiscountCompayAccrues" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
	<xs:element name="GovernmentRebateAndChargebackAccruals" id="regn_GovernmentRebateAndChargebackAccruals" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant"/>
	<xs:element name="DistributionRelatedFeesAccruals" id="regn_DistributionRelatedFeesAccruals" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant"/>
	<xs:element name="SharedPreLaunchCommercializationExpensesWithCollaborator" id="regn_SharedPreLaunchCommercializationExpensesWithCollaborator" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="StartingSpecifiedLevelsOfAnnualSalesAtWhichSalesMilestonePaymentsMayBeReceived" id="regn_StartingSpecifiedLevelsOfAnnualSalesAtWhichSalesMilestonePaymentsMayBeReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration"/>
	<xs:element name="ArcalystNetProductSalesMember" id="regn_ArcalystNetProductSalesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="CostsIncurredByLandlordToConstructNewLaboratoryAndOfficeFacilities" id="regn_CostsIncurredByLandlordToConstructNewLaboratoryAndOfficeFacilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
	<xs:element name="SubstantiveMilestonePaymentToCompanyUnderCertainDefinedCircumstances" id="regn_SubstantiveMilestonePaymentToCompanyUnderCertainDefinedCircumstances" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="duration"/>
	<xs:element name="AdjustmentToAdditionalPaidInCapitalCostOfConvertibleNoteHedge" id="regn_AdjustmentToAdditionalPaidInCapitalCostOfConvertibleNoteHedge" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="PurchaseOfConvertibleNoteHedges" id="regn_PurchaseOfConvertibleNoteHedges" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="GrossProceedsFromIssuanceOfNotes" id="regn_GrossProceedsFromIssuanceOfNotes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="Debtinstrumentissuanceatpercentofpar" id="regn_Debtinstrumentissuanceatpercentofpar" type="num:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
	<xs:element name="CompanyIncurredExpensesAssociatedWithSanofiCollaborations" id="regn_CompanyIncurredExpensesAssociatedWithSanofiCollaborations" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="NumberOfSharesOfCommonStockPurchasedInShares" id="regn_NumberOfSharesOfCommonStockPurchasedInShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="instant"/>
	<xs:element name="SubstantiveMilestonePaymentToCompany" id="regn_SubstantiveMilestonePaymentToCompany" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration"/>
	<xs:element name="PayableToBayerHealthcare" id="regn_PayableToBayerHealthcare" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="credit" xbrli:periodType="instant"/>
	<xs:element name="IssuanceCosts" id="regn_IssuanceCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant"/>
	<xs:element name="NonExclusiveLicenseAgreementTerm" id="regn_NonExclusiveLicenseAgreementTerm" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="RecognitionPeriodForAdvancePayment" id="regn_RecognitionPeriodForAdvancePayment" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="NumberOfDaysOfAdvanceWrittenNoticeToTerminateAgreement" id="regn_NumberOfDaysOfAdvanceWrittenNoticeToTerminateAgreement" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="PeriodOverWhichAnnualPaymentIsRecognizedAsRevenue" id="regn_PeriodOverWhichAnnualPaymentIsRecognizedAsRevenue" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPeriodFromVestingDateAwardsMayBeReceived" id="regn_ShareBasedCompensationArrangementByShareBasedPaymentAwardPeriodFromVestingDateAwardsMayBeReceived" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/>
	<xs:element name="PeriodOfFunding" id="regn_PeriodOfFunding" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration"/></xs:schema>
</XBRL>
