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  <xs:element id="halo_ComputerAndOfficeEquipmentMember" abstract="true" name="ComputerAndOfficeEquipmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="halo_OperatingLeaseAccretionOfLiability" abstract="false" name="OperatingLeaseAccretionOfLiability" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="halo_AccruedOutsourcedManufacturingExpenses" abstract="false" name="AccruedOutsourcedManufacturingExpenses" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="halo_AccruedLiabilitiesNoncurrent" abstract="false" name="AccruedLiabilitiesNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="halo_AutoInjectorTechnologyPlatformMember" abstract="true" name="AutoInjectorTechnologyPlatformMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="halo_XYOSTEDProprietaryProductMember" abstract="true" name="XYOSTEDProprietaryProductMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="halo_TLANDOProductRightsMember" abstract="true" name="TLANDOProductRightsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="halo_FiniteLivedIntangibleAssetExpectedAmortizationAfterYearFour" abstract="false" name="FiniteLivedIntangibleAssetExpectedAmortizationAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="halo_A0.875ConvertibleSeniorNotesDue2032Member" abstract="true" name="A0.875ConvertibleSeniorNotesDue2032Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="halo_A0.00ConvertibleSeniorNotesDue2031Member" abstract="true" name="A0.00ConvertibleSeniorNotesDue2031Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="halo_A100ConvertibleSeniorNotesDue2028Member" abstract="true" name="A100ConvertibleSeniorNotesDue2028Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="halo_A025ConvertibleSeniorNotesDue2027Member" abstract="true" name="A025ConvertibleSeniorNotesDue2027Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="halo_CreditAgreementMember" abstract="true" name="CreditAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="halo_TermLoanFacilityMember" abstract="true" name="TermLoanFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="halo_VariableRateComponentAxis" abstract="true" name="VariableRateComponentAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="halo_VariableRateComponentDomain" abstract="true" name="VariableRateComponentDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="halo_VariableRateComponentTwoMember" abstract="true" name="VariableRateComponentTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="halo_DebtInstrumentConvertibleThresholdConsecutiveBusinessDays" abstract="false" name="DebtInstrumentConvertibleThresholdConsecutiveBusinessDays" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="halo_DebtInstrumentCapCallTransactionCapPricePerShare" abstract="false" name="DebtInstrumentCapCallTransactionCapPricePerShare" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="halo_SaleOfStockPremiumOverLastReportedSalePricePercentage" abstract="false" name="SaleOfStockPremiumOverLastReportedSalePricePercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="halo_PaymentForCappedCallTransactions" abstract="false" name="PaymentForCappedCallTransactions" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="halo_A0.25ConvertibleSeniorNotesDue2027Member" abstract="true" name="A0.25ConvertibleSeniorNotesDue2027Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="halo_A2021ESPPPlanMember" abstract="true" name="A2021ESPPPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="halo_A2024CapitalReturnProgramMember" abstract="true" name="A2024CapitalReturnProgramMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="halo_A2024CapitalReturnProgramTrancheTwoMember" abstract="true" name="A2024CapitalReturnProgramTrancheTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="halo_A2024CapitalReturnProgramTrancheThreeMember" abstract="true" name="A2024CapitalReturnProgramTrancheThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="halo_ShareBasedCompensationArrangementByShareBasedPaymentAwardMinimumEmployeeSubscriptionRate" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardMinimumEmployeeSubscriptionRate" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="halo_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscriptionAmount" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscriptionAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="halo_ShareBasedCompensationArrangementByShareBasedPaymentAwardPurchasePeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPurchasePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="halo_RSURSAandPRSUawardsMember" abstract="true" name="RSURSAandPRSUawardsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="halo_ScheduleofSharebasedCompensationArrangementsValuationInputsTable" abstract="true" name="ScheduleofSharebasedCompensationArrangementsValuationInputsTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="halo_ScheduleofSharebasedCompensationArrangementsValuationInputsLineItems" abstract="true" name="ScheduleofSharebasedCompensationArrangementsValuationInputsLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="halo_RestrictStockUnitsPerformanceSharesAndESPPMember" abstract="true" name="RestrictStockUnitsPerformanceSharesAndESPPMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="halo_MaheshKrishnanMember" abstract="true" name="MaheshKrishnanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
