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    <link:label id="lab_exel_PercentOfRoyaltyOnNetSale_B9A5FC064745AFB7ED5DD293EBBD0643_terseLabel_en-US" xlink:label="lab_exel_PercentOfRoyaltyOnNetSale_B9A5FC064745AFB7ED5DD293EBBD0643" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Percent of royalty on net sale</link:label>
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    <link:loc xlink:href="exel-20171229.xsd#exel_ResearchandDevelopmentArrangementPerformedforOthersReimbursementforCostsIncurredPercent" xlink:label="loc_exel_ResearchandDevelopmentArrangementPerformedforOthersReimbursementforCostsIncurredPercent_17D9A67F58E48E842F49D293EBBD09AD" xlink:type="locator" />
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    <link:loc xlink:href="exel-20171229.xsd#exel_CollaborativeArrangementAchievementLevelsofCommercialPerformancePeriod" xlink:label="loc_exel_CollaborativeArrangementAchievementLevelsofCommercialPerformancePeriod_3A2A2B0ADFD96C0DCA8FD293EBBD0CAD" xlink:type="locator" />
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    <link:label id="lab_us-gaap_ContractsRevenue_84DBE8CDFDFBEBB2EE11D294A5C8E6BB_verboseLabel_en-US" xlink:label="lab_us-gaap_ContractsRevenue_84DBE8CDFDFBEBB2EE11D294A5C8E6BB" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Collaboration revenues</link:label>
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    <link:label id="lab_us-gaap_DeferredRevenueCurrent_7EE54ED0B5E90C189DF3D293EBBDBB0D_label_en-US" xlink:label="lab_us-gaap_DeferredRevenueCurrent_7EE54ED0B5E90C189DF3D293EBBDBB0D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Revenue, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredRevenueCurrent" xlink:label="loc_us-gaap_DeferredRevenueCurrent_7EE54ED0B5E90C189DF3D293EBBDBB0D" xlink:type="locator" />
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    <link:label id="lab_exel_PeriodOfSpecificSalesVolumeThreshold_AF9642ADDFE0A0EA72FFD2CE15773585_label_en-US" xlink:label="lab_exel_PeriodOfSpecificSalesVolumeThreshold_AF9642ADDFE0A0EA72FFD2CE15773585" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Period Of Specific Sales Volume, Threshold</link:label>
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    <link:label id="lab_us-gaap_StatementOfCashFlowsAbstract_A90EF6111D63AD39DFFBD2589C9F431C_label_en-US" xlink:label="lab_us-gaap_StatementOfCashFlowsAbstract_A90EF6111D63AD39DFFBD2589C9F431C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statement of Cash Flows [Abstract]</link:label>
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    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncreaseDecreaseInOtherOperatingLiabilities" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherOperatingLiabilities_959ECC6EC515482DC7A7D2589CA05E81" xlink:type="locator" />
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    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFiveYears" xlink:label="loc_us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFiveYears_D7DF68080BB946B8821FBDF289B10E36" xlink:type="locator" />
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    <link:label id="lab_exel_AccruedCollaborationLiabilityCurrent_78B6179916FB848E2904B9A113AC2EAA_documentation_en-US" xlink:label="lab_exel_AccruedCollaborationLiabilityCurrent_78B6179916FB848E2904B9A113AC2EAA" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Accrued Collaboration Liability, Current</link:label>
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    <link:label id="lab_us-gaap_ConvertibleDebtCurrent_13A093F315AABAA3AAFCB9A113ACE7EF_label_en-US" xlink:label="lab_us-gaap_ConvertibleDebtCurrent_13A093F315AABAA3AAFCB9A113ACE7EF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Convertible Debt, Current</link:label>
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