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    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LimitedLiabilityCompanyLLCOrLimitedPartnershipLPMembersOrLimitedPartnersOwnershipInterest" xlink:label="loc_us-gaap_LimitedLiabilityCompanyLLCOrLimitedPartnershipLPMembersOrLimitedPartnersOwnershipInterest" xlink:title="LimitedLiabilityCompanyLLCOrLimitedPartnershipLPMembersOrLimitedPartnersOwnershipInterest" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_pagp_MembersEquityLineItems" xlink:to="loc_us-gaap_LimitedLiabilityCompanyLLCOrLimitedPartnershipLPMembersOrLimitedPartnersOwnershipInterest" xlink:title="Definition : loc_pagp_MembersEquityLineItems to loc_us-gaap_LimitedLiabilityCompanyLLCOrLimitedPartnershipLPMembersOrLimitedPartnersOwnershipInterest" use="optional" order="3.0" />
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  <link:definitionLink xlink:type="extended" xlink:role="http://www.paagp.com/role/DisclosureMembersEquityDetails2">
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  <link:definitionLink xlink:type="extended" xlink:role="http://www.paagp.com/role/DisclosureGoodwillDetails">
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    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis" xlink:to="SegmentDomain_1" xlink:title="Definition : loc_us-gaap_StatementBusinessSegmentsAxis to loc_us-gaap_SegmentDomain" use="optional" order="2.0" />
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    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain" xlink:to="loc_pagp_SegmentPipelineTariffActivitiesTruckingMember" xlink:title="Definition : loc_us-gaap_SegmentDomain to loc_pagp_SegmentPipelineTariffActivitiesTruckingMember" use="optional" order="1.0" />
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    <link:loc xlink:type="locator" xlink:href="pagp-20130930.xsd#pagp_SegmentSalesAndLogisticsMember" xlink:label="loc_pagp_SegmentSalesAndLogisticsMember" xlink:title="SegmentSalesAndLogisticsMember" />
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  <link:definitionLink xlink:type="extended" xlink:role="http://www.paagp.com/role/DisclosureOrganizationAndBasisOfPresentationDetails2">
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    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_SubsequentEventMember" xlink:label="loc_us-gaap_SubsequentEventMember" xlink:title="SubsequentEventMember" />
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    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="RelatedPartyTransactionsByRelatedPartyAxis" xlink:title="RelatedPartyTransactionsByRelatedPartyAxis" />
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    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RelatedPartyDomain" xlink:to="PlainsAAPLPMember" xlink:title="definition: RelatedPartyDomain to PlainsAAPLPMember" order="1.0" />
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    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis" xlink:to="loc_dei_EntityDomain" xlink:title="Definition : loc_dei_LegalEntityAxis to loc_dei_EntityDomain" order="1.0" />
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    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementScenarioAxis" xlink:to="loc_us-gaap_ScenarioUnspecifiedDomain" xlink:title="Definition : loc_us-gaap_StatementScenarioAxis to loc_us-gaap_ScenarioUnspecifiedDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ScenarioPlanMember" xlink:label="loc_us-gaap_ScenarioPlanMember" xlink:title="ScenarioPlanMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScenarioUnspecifiedDomain" xlink:to="loc_us-gaap_ScenarioPlanMember" xlink:title="Definition : loc_us-gaap_ScenarioUnspecifiedDomain to loc_us-gaap_ScenarioPlanMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PartnerCapitalComponentsAxis" xlink:label="loc_us-gaap_PartnerCapitalComponentsAxis" xlink:title="PartnerCapitalComponentsAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PartnerCapitalComponentsDomain" xlink:label="loc_us-gaap_PartnerCapitalComponentsDomain" xlink:title="PartnerCapitalComponentsDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PartnerCapitalComponentsAxis" xlink:to="loc_us-gaap_PartnerCapitalComponentsDomain" xlink:title="Definition : loc_us-gaap_PartnerCapitalComponentsAxis to loc_us-gaap_PartnerCapitalComponentsDomain" order="1.0" />
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