10-Q 1 mplx-20210930.htm 10-Q mplx-20210930
2021Q30001552000--12-31falseP5YP5YP5YP5Y312300015520002021-01-012021-09-30xbrli:shares00015520002021-10-29iso4217:USD0001552000us-gaap:ServiceMember2021-07-012021-09-300001552000us-gaap:ServiceMember2020-07-012020-09-300001552000us-gaap:ServiceMember2021-01-012021-09-300001552000us-gaap:ServiceMember2020-01-012020-09-300001552000us-gaap:ServiceOtherMember2021-07-012021-09-300001552000us-gaap:ServiceOtherMember2020-07-012020-09-300001552000us-gaap:ServiceOtherMember2021-01-012021-09-300001552000us-gaap:ServiceOtherMember2020-01-012020-09-300001552000mplx:ThirdPartyMember2021-07-012021-09-300001552000mplx:ThirdPartyMember2020-07-012020-09-300001552000mplx:ThirdPartyMember2021-01-012021-09-300001552000mplx:ThirdPartyMember2020-01-012020-09-3000015520002021-07-012021-09-3000015520002020-07-012020-09-3000015520002020-01-012020-09-300001552000us-gaap:ProductMember2021-07-012021-09-300001552000us-gaap:ProductMember2020-07-012020-09-300001552000us-gaap:ProductMember2021-01-012021-09-300001552000us-gaap:ProductMember2020-01-012020-09-300001552000mplx:MarathonPetroleumCorporationMemberus-gaap:ProductMember2021-07-012021-09-300001552000mplx:MarathonPetroleumCorporationMemberus-gaap:ProductMember2020-07-012020-09-300001552000mplx:MarathonPetroleumCorporationMemberus-gaap:ProductMember2021-01-012021-09-300001552000mplx:MarathonPetroleumCorporationMemberus-gaap:ProductMember2020-01-012020-09-300001552000mplx:MarathonPetroleumCorporationMember2021-07-012021-09-300001552000mplx:MarathonPetroleumCorporationMember2020-07-012020-09-300001552000mplx:MarathonPetroleumCorporationMember2021-01-012021-09-300001552000mplx:MarathonPetroleumCorporationMember2020-01-012020-09-300001552000us-gaap:OilAndGasRefiningAndMarketingMember2021-07-012021-09-300001552000us-gaap:OilAndGasRefiningAndMarketingMember2020-07-012020-09-300001552000us-gaap:OilAndGasRefiningAndMarketingMember2021-01-012021-09-300001552000us-gaap:OilAndGasRefiningAndMarketingMember2020-01-012020-09-300001552000us-gaap:NaturalGasMidstreamMember2021-07-012021-09-300001552000us-gaap:NaturalGasMidstreamMember2020-07-012020-09-300001552000us-gaap:NaturalGasMidstreamMember2021-01-012021-09-300001552000us-gaap:NaturalGasMidstreamMember2020-01-012020-09-300001552000mplx:RentalCostOfSalesMember2021-07-012021-09-300001552000mplx:RentalCostOfSalesMember2020-07-012020-09-300001552000mplx:RentalCostOfSalesMember2021-01-012021-09-300001552000mplx:RentalCostOfSalesMember2020-01-012020-09-300001552000mplx:MarathonPetroleumCorporationMembermplx:RentalcostofsalesrelatedpartiesMember2021-07-012021-09-300001552000mplx:MarathonPetroleumCorporationMembermplx:RentalcostofsalesrelatedpartiesMember2020-07-012020-09-300001552000mplx:MarathonPetroleumCorporationMembermplx:RentalcostofsalesrelatedpartiesMember2021-01-012021-09-300001552000mplx:MarathonPetroleumCorporationMembermplx:RentalcostofsalesrelatedpartiesMember2020-01-012020-09-300001552000mplx:RelatedPartyAndThirdPartyMember2021-07-012021-09-300001552000mplx:RelatedPartyAndThirdPartyMember2020-07-012020-09-300001552000mplx:RelatedPartyAndThirdPartyMember2021-01-012021-09-300001552000mplx:RelatedPartyAndThirdPartyMember2020-01-012020-09-300001552000us-gaap:SeriesAPreferredStockMemberus-gaap:PreferredPartnerMember2021-07-012021-09-300001552000us-gaap:SeriesAPreferredStockMemberus-gaap:PreferredPartnerMember2020-07-012020-09-300001552000us-gaap:SeriesAPreferredStockMemberus-gaap:PreferredPartnerMember2021-01-012021-09-300001552000us-gaap:SeriesAPreferredStockMemberus-gaap:PreferredPartnerMember2020-01-012020-09-300001552000us-gaap:SeriesBPreferredStockMemberus-gaap:PreferredPartnerMember2021-07-012021-09-300001552000us-gaap:SeriesBPreferredStockMemberus-gaap:PreferredPartnerMember2020-07-012020-09-300001552000us-gaap:SeriesBPreferredStockMemberus-gaap:PreferredPartnerMember2021-01-012021-09-300001552000us-gaap:SeriesBPreferredStockMemberus-gaap:PreferredPartnerMember2020-01-012020-09-30iso4217:USDxbrli:shares0001552000mplx:LimitedPartnersCommonUnitsMember2021-07-012021-09-300001552000mplx:LimitedPartnersCommonUnitsMember2020-07-012020-09-300001552000mplx:LimitedPartnersCommonUnitsMember2021-01-012021-09-300001552000mplx:LimitedPartnersCommonUnitsMember2020-01-012020-09-3000015520002021-04-012021-06-3000015520002021-09-3000015520002020-12-310001552000mplx:ThirdPartyMember2021-09-300001552000mplx:ThirdPartyMember2020-12-310001552000srt:AffiliatedEntityMember2021-09-300001552000srt:AffiliatedEntityMember2020-12-310001552000mplx:SeriesAConvertiblePreferredUnitsMember2021-09-300001552000mplx:SeriesAConvertiblePreferredUnitsMember2020-12-310001552000mplx:LimitedPartnersCommonUnitsMembermplx:PublicMember2021-09-300001552000mplx:LimitedPartnersCommonUnitsMembermplx:PublicMember2020-12-310001552000mplx:MarathonPetroleumCorporationMembermplx:LimitedPartnersCommonUnitsMember2021-09-300001552000mplx:MarathonPetroleumCorporationMembermplx:LimitedPartnersCommonUnitsMember2020-12-310001552000us-gaap:SeriesBPreferredStockMember2021-09-300001552000us-gaap:SeriesBPreferredStockMember2020-12-310001552000mplx:LoopLlcandExplorerPipelineMember2021-09-300001552000mplx:LoopLlcandExplorerPipelineMember2020-12-310001552000mplx:MPCInvestmentMembermplx:RelatedPartyRevolvingCreditAgreementMember2021-01-012021-09-300001552000mplx:MPCInvestmentMembermplx:RelatedPartyRevolvingCreditAgreementMember2020-01-012020-09-3000015520002019-12-3100015520002020-09-300001552000mplx:LimitedPartnersCommonUnitsMembermplx:PublicMember2019-12-310001552000mplx:MarathonPetroleumCorporationMembermplx:LimitedPartnersCommonUnitsMember2019-12-310001552000us-gaap:SeriesBPreferredStockMember2019-12-310001552000mplx:LoopLlcandExplorerPipelineMember2019-12-310001552000mplx:LimitedPartnersCommonUnitsMembermplx:PublicMember2020-01-012020-03-310001552000mplx:MarathonPetroleumCorporationMembermplx:LimitedPartnersCommonUnitsMember2020-01-012020-03-310001552000us-gaap:SeriesBPreferredStockMember2020-01-012020-03-310001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2020-01-012020-03-310001552000us-gaap:NoncontrollingInterestMember2020-01-012020-03-3100015520002020-01-012020-03-310001552000mplx:LimitedPartnersCommonUnitsMembermplx:PublicMember2020-03-310001552000mplx:MarathonPetroleumCorporationMembermplx:LimitedPartnersCommonUnitsMember2020-03-310001552000us-gaap:SeriesBPreferredStockMember2020-03-310001552000mplx:LoopLlcandExplorerPipelineMember2020-03-3100015520002020-03-310001552000mplx:LimitedPartnersCommonUnitsMembermplx:PublicMember2020-04-012020-06-300001552000mplx:MarathonPetroleumCorporationMembermplx:LimitedPartnersCommonUnitsMember2020-04-012020-06-300001552000us-gaap:SeriesBPreferredStockMember2020-04-012020-06-300001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2020-04-012020-06-300001552000us-gaap:NoncontrollingInterestMember2020-04-012020-06-3000015520002020-04-012020-06-300001552000mplx:LimitedPartnersCommonUnitsMembermplx:PublicMember2020-06-300001552000mplx:MarathonPetroleumCorporationMembermplx:LimitedPartnersCommonUnitsMember2020-06-300001552000us-gaap:SeriesBPreferredStockMember2020-06-300001552000mplx:LoopLlcandExplorerPipelineMember2020-06-3000015520002020-06-300001552000mplx:LimitedPartnersCommonUnitsMembermplx:PublicMember2020-07-012020-09-300001552000mplx:MarathonPetroleumCorporationMembermplx:LimitedPartnersCommonUnitsMember2020-07-012020-09-300001552000us-gaap:SeriesBPreferredStockMember2020-07-012020-09-300001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2020-07-012020-09-300001552000us-gaap:NoncontrollingInterestMember2020-07-012020-09-300001552000mplx:LimitedPartnersCommonUnitsMembermplx:PublicMember2020-09-300001552000mplx:MarathonPetroleumCorporationMembermplx:LimitedPartnersCommonUnitsMember2020-09-300001552000us-gaap:SeriesBPreferredStockMember2020-09-300001552000mplx:LoopLlcandExplorerPipelineMember2020-09-300001552000mplx:LimitedPartnersCommonUnitsMembermplx:PublicMember2021-01-012021-03-310001552000mplx:MarathonPetroleumCorporationMembermplx:LimitedPartnersCommonUnitsMember2021-01-012021-03-310001552000us-gaap:SeriesBPreferredStockMember2021-01-012021-03-310001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2021-01-012021-03-310001552000us-gaap:NoncontrollingInterestMember2021-01-012021-03-3100015520002021-01-012021-03-310001552000mplx:LimitedPartnersCommonUnitsMembermplx:PublicMember2021-03-310001552000mplx:MarathonPetroleumCorporationMembermplx:LimitedPartnersCommonUnitsMember2021-03-310001552000us-gaap:SeriesBPreferredStockMember2021-03-310001552000mplx:LoopLlcandExplorerPipelineMember2021-03-3100015520002021-03-310001552000mplx:LimitedPartnersCommonUnitsMembermplx:PublicMember2021-04-012021-06-300001552000mplx:MarathonPetroleumCorporationMembermplx:LimitedPartnersCommonUnitsMember2021-04-012021-06-300001552000us-gaap:SeriesBPreferredStockMember2021-04-012021-06-300001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2021-04-012021-06-300001552000us-gaap:NoncontrollingInterestMember2021-04-012021-06-300001552000mplx:LimitedPartnersCommonUnitsMembermplx:PublicMember2021-06-300001552000mplx:MarathonPetroleumCorporationMembermplx:LimitedPartnersCommonUnitsMember2021-06-300001552000us-gaap:SeriesBPreferredStockMember2021-06-300001552000mplx:LoopLlcandExplorerPipelineMember2021-06-3000015520002021-06-300001552000mplx:LimitedPartnersCommonUnitsMembermplx:PublicMember2021-07-012021-09-300001552000mplx:MarathonPetroleumCorporationMembermplx:LimitedPartnersCommonUnitsMember2021-07-012021-09-300001552000us-gaap:SeriesBPreferredStockMember2021-07-012021-09-300001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2021-07-012021-09-300001552000us-gaap:NoncontrollingInterestMember2021-07-012021-09-30xbrli:pure0001552000mplx:GatheringandProcessingMember2020-01-012020-03-310001552000mplx:SaleOfJavelinaAssetsAndLiabilitiesMember2021-01-012021-09-300001552000mplx:WesternRefiningWholesaleWesternRefiningProductTransportMember2020-07-312020-07-310001552000mplx:WesternRefiningWholesaleWesternRefiningProductTransportMember2020-07-310001552000mplx:MarEnBakkenCompanyLLCMember2021-09-300001552000mplx:MarEnBakkenCompanyLLCMembermplx:LogisticsandStorageMember2021-09-300001552000mplx:MarEnBakkenCompanyLLCMembermplx:LogisticsandStorageMember2020-12-310001552000mplx:IllinoisExtensionPipelineCompanyLLCMember2021-09-300001552000mplx:LogisticsandStorageMembermplx:IllinoisExtensionPipelineCompanyLLCMember2021-09-300001552000mplx:LogisticsandStorageMembermplx:IllinoisExtensionPipelineCompanyLLCMember2020-12-310001552000mplx:LoopLlcMember2021-09-300001552000mplx:LoopLlcMembermplx:LogisticsandStorageMember2021-09-300001552000mplx:LoopLlcMembermplx:LogisticsandStorageMember2020-12-310001552000mplx:AndeavorLogisticsRioPipelineMember2021-09-300001552000mplx:LogisticsandStorageMembermplx:AndeavorLogisticsRioPipelineMember2021-09-300001552000mplx:LogisticsandStorageMembermplx:AndeavorLogisticsRioPipelineMember2020-12-310001552000mplx:MinnesotaPipeLineCompanyLLCMember2021-09-300001552000mplx:LogisticsandStorageMembermplx:MinnesotaPipeLineCompanyLLCMember2021-09-300001552000mplx:LogisticsandStorageMembermplx:MinnesotaPipeLineCompanyLLCMember2020-12-310001552000mplx:WhistlerPipelineLLCMember2021-09-300001552000mplx:WhistlerPipelineLLCMembermplx:LogisticsandStorageMember2021-09-300001552000mplx:WhistlerPipelineLLCMembermplx:LogisticsandStorageMember2020-12-310001552000mplx:ExplorerPipelineMember2021-09-300001552000mplx:ExplorerPipelineMembermplx:LogisticsandStorageMember2021-09-300001552000mplx:ExplorerPipelineMembermplx:LogisticsandStorageMember2020-12-310001552000mplx:W2WHoldingsLLCMember2021-09-300001552000mplx:W2WHoldingsLLCMembermplx:LogisticsandStorageMember2021-09-300001552000mplx:W2WHoldingsLLCMembermplx:LogisticsandStorageMember2020-12-310001552000mplx:OtherVIEsandNonVIEsMembermplx:LogisticsandStorageMember2021-09-300001552000mplx:OtherVIEsandNonVIEsMembermplx:LogisticsandStorageMember2020-12-310001552000mplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMember2021-09-300001552000mplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMember2020-12-310001552000mplx:MarkWestUticaEMGMember2021-09-300001552000mplx:GatheringandProcessingMembermplx:MarkWestUticaEMGMember2021-09-300001552000mplx:GatheringandProcessingMembermplx:MarkWestUticaEMGMember2020-12-310001552000mplx:SherwoodMidstreamLLCMember2021-09-300001552000mplx:GatheringandProcessingMembermplx:SherwoodMidstreamLLCMember2021-09-300001552000mplx:GatheringandProcessingMembermplx:SherwoodMidstreamLLCMember2020-12-310001552000mplx:MarkWestEMGJeffersonDryGasGatheringCompanyL.L.C.Member2021-09-300001552000mplx:GatheringandProcessingMembermplx:MarkWestEMGJeffersonDryGasGatheringCompanyL.L.C.Member2021-09-300001552000mplx:GatheringandProcessingMembermplx:MarkWestEMGJeffersonDryGasGatheringCompanyL.L.C.Member2020-12-310001552000mplx:MarkWestTornadoGPLLCMember2021-09-300001552000mplx:GatheringandProcessingMembermplx:MarkWestTornadoGPLLCMember2021-09-300001552000mplx:GatheringandProcessingMembermplx:MarkWestTornadoGPLLCMember2020-12-310001552000mplx:RendezvousGasServicesL.L.C.Member2021-09-300001552000mplx:GatheringandProcessingMembermplx:RendezvousGasServicesL.L.C.Member2021-09-300001552000mplx:GatheringandProcessingMembermplx:RendezvousGasServicesL.L.C.Member2020-12-310001552000mplx:DirectOwnershipInterestMembermplx:SherwoodMidstreamHoldingsMember2021-09-300001552000mplx:GatheringandProcessingMembermplx:SherwoodMidstreamHoldingsMember2021-09-300001552000mplx:GatheringandProcessingMembermplx:SherwoodMidstreamHoldingsMember2020-12-310001552000mplx:CentrahomaProcessingLLCMember2021-09-300001552000mplx:GatheringandProcessingMembermplx:CentrahomaProcessingLLCMember2021-09-300001552000mplx:GatheringandProcessingMembermplx:CentrahomaProcessingLLCMember2020-12-310001552000mplx:GatheringandProcessingMembermplx:OtherVIEsandNonVIEsMember2021-09-300001552000mplx:GatheringandProcessingMembermplx:OtherVIEsandNonVIEsMember2020-12-310001552000mplx:GatheringandProcessingMemberus-gaap:OperatingSegmentsMember2021-09-300001552000mplx:GatheringandProcessingMemberus-gaap:OperatingSegmentsMember2020-12-310001552000mplx:IndirectOwnershipInterestMembermplx:BakkenPipelineSystemMember2021-09-300001552000mplx:IndirectOwnershipInterestMembermplx:WinktoWebsterPipelineLLCMember2021-09-300001552000mplx:IndirectOwnershipInterestMembermplx:SherwoodMidstreamHoldingsMember2021-09-300001552000mplx:MarkWestUticaEMGMember2020-01-012020-03-310001552000mplx:OtherVIEsMember2021-01-012021-09-300001552000mplx:NonVIEsMember2021-01-012021-09-300001552000mplx:OtherVIEsandNonVIEsMember2021-01-012021-09-300001552000mplx:OtherVIEsMember2020-01-012020-09-300001552000mplx:NonVIEsMember2020-01-012020-09-300001552000mplx:OtherVIEsandNonVIEsMember2020-01-012020-09-300001552000mplx:OtherVIEsMember2021-09-300001552000mplx:NonVIEsMember2021-09-300001552000mplx:OtherVIEsandNonVIEsMember2021-09-300001552000mplx:OtherVIEsMember2020-12-310001552000mplx:NonVIEsMember2020-12-310001552000mplx:OtherVIEsandNonVIEsMember2020-12-310001552000mplx:MPCInvestmentMembermplx:RelatedPartyRevolvingCreditAgreementMember2019-07-310001552000mplx:MPCInvestmentMembermplx:RelatedPartyRevolvingCreditAgreementMember2019-07-312019-07-310001552000mplx:MPCInvestmentMembermplx:RelatedPartyRevolvingCreditAgreementMember2020-01-012020-12-310001552000mplx:MPCInvestmentMembermplx:RelatedPartyRevolvingCreditAgreementMember2021-09-300001552000mplx:MPCInvestmentMembermplx:RelatedPartyRevolvingCreditAgreementMember2020-12-310001552000mplx:MarathonPetroleumCorporationMemberus-gaap:AssetUnderConstructionMember2021-07-012021-09-300001552000mplx:MarathonPetroleumCorporationMemberus-gaap:AssetUnderConstructionMember2021-01-012021-09-300001552000mplx:MarathonPetroleumCorporationMemberus-gaap:AssetUnderConstructionMember2020-07-012020-09-300001552000mplx:MarathonPetroleumCorporationMemberus-gaap:AssetUnderConstructionMember2020-01-012020-09-300001552000mplx:MarathonPetroleumCorporationMember2020-01-012020-12-310001552000mplx:MarathonPetroleumCorporationMember2021-09-300001552000mplx:MarathonPetroleumCorporationMember2020-12-310001552000us-gaap:OtherAffiliatesMember2021-09-300001552000us-gaap:OtherAffiliatesMember2020-12-310001552000mplx:MarathonPetroleumCorporationMembermplx:MinimumCommittedVolumeContractsMember2021-09-300001552000mplx:MarathonPetroleumCorporationMembermplx:MinimumCommittedVolumeContractsMember2020-12-310001552000mplx:MarathonPetroleumCorporationMembermplx:ReimbursableProjectsMember2021-09-300001552000mplx:MarathonPetroleumCorporationMembermplx:ReimbursableProjectsMember2020-12-310001552000mplx:ReimbursableProjectsMemberus-gaap:OtherAffiliatesMember2021-09-300001552000mplx:ReimbursableProjectsMemberus-gaap:OtherAffiliatesMember2020-12-310001552000mplx:LimitedPartnersCommonUnitsMember2020-12-310001552000mplx:LimitedPartnersCommonUnitsMember2021-09-300001552000us-gaap:SubsequentEventMember2021-10-012021-10-040001552000us-gaap:SeriesBPreferredStockMembermplx:ANDXLPMember2019-07-290001552000us-gaap:SeriesBPreferredStockMembermplx:ANDXLPMember2019-07-292019-07-290001552000us-gaap:SeriesBPreferredStockMembermplx:ANDXLPMemberus-gaap:PreferredPartnerMember2021-01-012021-09-300001552000us-gaap:SeriesBPreferredStockMembermplx:ANDXLPMember2021-01-012021-09-300001552000us-gaap:SubsequentEventMember2021-10-262021-10-260001552000mplx:BaseQuarterlyDistributionMemberus-gaap:SubsequentEventMember2021-10-262021-10-260001552000us-gaap:SubsequentEventMembermplx:SpecialDistributionMember2021-10-262021-10-260001552000mplx:LimitedPartnersCommonUnitsMemberus-gaap:SubsequentEventMember2021-11-122021-11-120001552000us-gaap:SubsequentEventMember2021-11-052021-11-0500015520002021-04-272021-04-2700015520002020-04-282020-04-2800015520002021-07-272021-07-2700015520002020-07-282020-07-2800015520002020-10-272020-10-270001552000us-gaap:SeriesBPreferredStockMember2021-08-162021-08-160001552000mplx:LimitedPartnersCommonUnitsMemberus-gaap:CommonStockMember2021-07-012021-09-300001552000mplx:LimitedPartnersCommonUnitsMemberus-gaap:CommonStockMember2020-07-012020-09-300001552000mplx:LimitedPartnersCommonUnitsMemberus-gaap:CommonStockMember2021-01-012021-09-300001552000mplx:LimitedPartnersCommonUnitsMemberus-gaap:CommonStockMember2020-01-012020-09-300001552000mplx:SeriesAConvertiblePreferredUnitsMember2016-05-132016-05-130001552000mplx:SeriesAConvertiblePreferredUnitsMember2021-01-012021-09-300001552000us-gaap:ServiceMembermplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMember2021-07-012021-09-300001552000us-gaap:ServiceMembermplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMember2020-07-012020-09-300001552000us-gaap:ServiceMembermplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMember2021-01-012021-09-300001552000us-gaap:ServiceMembermplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMember2020-01-012020-09-300001552000mplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMember2021-07-012021-09-300001552000mplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMember2020-07-012020-09-300001552000mplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMember2021-01-012021-09-300001552000mplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMember2020-01-012020-09-300001552000mplx:LogisticsandStorageMemberus-gaap:ProductMemberus-gaap:OperatingSegmentsMember2021-07-012021-09-300001552000mplx:LogisticsandStorageMemberus-gaap:ProductMemberus-gaap:OperatingSegmentsMember2020-07-012020-09-300001552000mplx:LogisticsandStorageMemberus-gaap:ProductMemberus-gaap:OperatingSegmentsMember2021-01-012021-09-300001552000mplx:LogisticsandStorageMemberus-gaap:ProductMemberus-gaap:OperatingSegmentsMember2020-01-012020-09-300001552000mplx:MarathonPetroleumCorporationMembermplx:LogisticsandStorageMember2021-07-012021-09-300001552000mplx:MarathonPetroleumCorporationMembermplx:LogisticsandStorageMember2020-07-012020-09-300001552000mplx:MarathonPetroleumCorporationMembermplx:LogisticsandStorageMember2021-01-012021-09-300001552000mplx:MarathonPetroleumCorporationMembermplx:LogisticsandStorageMember2020-01-012020-09-300001552000mplx:LogisticsandStorageMember2021-07-012021-09-300001552000mplx:LogisticsandStorageMember2020-07-012020-09-300001552000mplx:LogisticsandStorageMember2021-01-012021-09-300001552000mplx:LogisticsandStorageMember2020-01-012020-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ServiceMemberus-gaap:OperatingSegmentsMember2021-07-012021-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ServiceMemberus-gaap:OperatingSegmentsMember2020-07-012020-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ServiceMemberus-gaap:OperatingSegmentsMember2021-01-012021-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ServiceMemberus-gaap:OperatingSegmentsMember2020-01-012020-09-300001552000mplx:GatheringandProcessingMemberus-gaap:OperatingSegmentsMember2021-07-012021-09-300001552000mplx:GatheringandProcessingMemberus-gaap:OperatingSegmentsMember2020-07-012020-09-300001552000mplx:GatheringandProcessingMemberus-gaap:OperatingSegmentsMember2021-01-012021-09-300001552000mplx:GatheringandProcessingMemberus-gaap:OperatingSegmentsMember2020-01-012020-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ProductMemberus-gaap:OperatingSegmentsMember2021-07-012021-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ProductMemberus-gaap:OperatingSegmentsMember2020-07-012020-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ProductMemberus-gaap:OperatingSegmentsMember2021-01-012021-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ProductMemberus-gaap:OperatingSegmentsMember2020-01-012020-09-300001552000mplx:GatheringandProcessingMember2021-07-012021-09-300001552000mplx:GatheringandProcessingMember2020-07-012020-09-300001552000mplx:GatheringandProcessingMember2021-01-012021-09-300001552000mplx:GatheringandProcessingMember2020-01-012020-09-300001552000mplx:ThirdPartyMembermplx:LogisticsandStorageMember2021-07-012021-09-300001552000mplx:ThirdPartyMembermplx:LogisticsandStorageMember2021-01-012021-09-300001552000mplx:ThirdPartyMembermplx:LogisticsandStorageMember2020-07-012020-09-300001552000mplx:ThirdPartyMembermplx:LogisticsandStorageMember2020-01-012020-09-300001552000mplx:GatheringandProcessingMembermplx:ThirdPartyMember2021-07-012021-09-300001552000mplx:GatheringandProcessingMembermplx:ThirdPartyMember2021-01-012021-09-300001552000mplx:GatheringandProcessingMembermplx:ThirdPartyMember2020-07-012020-09-300001552000mplx:GatheringandProcessingMembermplx:ThirdPartyMember2020-01-012020-09-300001552000us-gaap:OperatingSegmentsMember2021-07-012021-09-300001552000us-gaap:OperatingSegmentsMember2020-07-012020-09-300001552000us-gaap:OperatingSegmentsMember2021-01-012021-09-300001552000us-gaap:OperatingSegmentsMember2020-01-012020-09-300001552000us-gaap:MaterialReconcilingItemsMember2021-07-012021-09-300001552000us-gaap:MaterialReconcilingItemsMember2020-07-012020-09-300001552000us-gaap:MaterialReconcilingItemsMember2021-01-012021-09-300001552000us-gaap:MaterialReconcilingItemsMember2020-01-012020-09-300001552000mplx:PurchasedproductcostsMemberus-gaap:NondesignatedMember2021-07-012021-09-300001552000mplx:PurchasedproductcostsMemberus-gaap:NondesignatedMember2020-07-012020-09-300001552000mplx:PurchasedproductcostsMemberus-gaap:NondesignatedMember2021-01-012021-09-300001552000mplx:PurchasedproductcostsMemberus-gaap:NondesignatedMember2020-01-012020-09-300001552000mplx:LogisticsandStorageMember2021-09-300001552000mplx:LogisticsandStorageMember2020-12-310001552000mplx:GatheringandProcessingMember2021-09-300001552000mplx:GatheringandProcessingMember2020-12-310001552000mplx:LogisticsandStorageMember2019-12-310001552000mplx:GatheringandProcessingMember2019-12-310001552000mplx:LogisticsandStorageMember2020-01-012020-12-310001552000mplx:GatheringandProcessingMember2020-01-012020-12-3100015520002020-01-012020-12-310001552000mplx:WesternRefiningWholesaleWesternRefiningProductTransportMembermplx:LogisticsandStorageMember2020-01-012020-12-310001552000mplx:GatheringandProcessingMembermplx:WesternRefiningWholesaleWesternRefiningProductTransportMember2020-01-012020-12-310001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:FairValueInputsLevel3Member2021-09-300001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:FairValueInputsLevel3Member2020-12-310001552000us-gaap:CommodityContractMemberus-gaap:NondesignatedMember2021-09-300001552000us-gaap:CommodityContractMemberus-gaap:NondesignatedMember2020-12-310001552000srt:MinimumMemberus-gaap:CommodityContractMemberus-gaap:FairValueInputsLevel3Member2021-09-300001552000srt:MaximumMemberus-gaap:CommodityContractMemberus-gaap:FairValueInputsLevel3Member2021-09-30iso4217:USDutr:gal0001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:FairValueInputsLevel3Member2021-01-012021-09-300001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMembermplx:NaturalGasMember2021-01-012021-09-300001552000us-gaap:CommodityContractMember2021-06-300001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMember2021-06-300001552000us-gaap:CommodityContractMember2020-06-300001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMember2020-06-300001552000us-gaap:CommodityContractMember2021-07-012021-09-300001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMember2021-07-012021-09-300001552000us-gaap:CommodityContractMember2020-07-012020-09-300001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMember2020-07-012020-09-300001552000us-gaap:CommodityContractMember2021-09-300001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMember2021-09-300001552000us-gaap:CommodityContractMember2020-09-300001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMember2020-09-300001552000us-gaap:CommodityContractMember2020-12-310001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMember2020-12-310001552000us-gaap:CommodityContractMember2019-12-310001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMember2019-12-310001552000us-gaap:CommodityContractMember2021-01-012021-09-300001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMember2021-01-012021-09-300001552000us-gaap:CommodityContractMember2020-01-012020-09-300001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMember2020-01-012020-09-300001552000us-gaap:EstimateOfFairValueFairValueDisclosureMember2021-09-300001552000us-gaap:CarryingReportedAmountFairValueDisclosureMember2021-09-300001552000us-gaap:EstimateOfFairValueFairValueDisclosureMember2020-12-310001552000us-gaap:CarryingReportedAmountFairValueDisclosureMember2020-12-310001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMembermplx:NaturalGasMember2021-09-300001552000us-gaap:OtherCurrentAssetsMemberus-gaap:CommodityContractMemberus-gaap:NondesignatedMember2021-09-300001552000us-gaap:CommodityContractMemberus-gaap:OtherCurrentLiabilitiesMemberus-gaap:NondesignatedMember2021-09-300001552000us-gaap:OtherCurrentAssetsMemberus-gaap:CommodityContractMemberus-gaap:NondesignatedMember2020-12-310001552000us-gaap:CommodityContractMemberus-gaap:OtherCurrentLiabilitiesMemberus-gaap:NondesignatedMember2020-12-310001552000us-gaap:OtherNoncurrentAssetsMemberus-gaap:CommodityContractMemberus-gaap:NondesignatedMember2021-09-300001552000us-gaap:OtherNoncurrentLiabilitiesMemberus-gaap:CommodityContractMemberus-gaap:NondesignatedMember2021-09-300001552000us-gaap:OtherNoncurrentAssetsMemberus-gaap:CommodityContractMemberus-gaap:NondesignatedMember2020-12-310001552000us-gaap:OtherNoncurrentLiabilitiesMemberus-gaap:CommodityContractMemberus-gaap:NondesignatedMember2020-12-310001552000mplx:PurchasedproductcostsMember2021-07-012021-09-300001552000mplx:PurchasedproductcostsMember2020-07-012020-09-300001552000mplx:PurchasedproductcostsMember2021-01-012021-09-300001552000mplx:PurchasedproductcostsMember2020-01-012020-09-300001552000mplx:MPLXRevolvingCreditFacilitydueJuly2024Member2021-09-300001552000mplx:MPLXRevolvingCreditFacilitydueJuly2024Member2020-12-310001552000mplx:VariableRateSeniorNotesMembermplx:MPLXLPMember2021-09-300001552000mplx:VariableRateSeniorNotesMembermplx:MPLXLPMember2020-12-310001552000mplx:MPLXLPMembermplx:FixedRateSeniorNotesMember2021-09-300001552000mplx:MPLXLPMembermplx:FixedRateSeniorNotesMember2020-12-310001552000mplx:MarkWestMembermplx:FixedRateSeniorNotesMember2021-09-300001552000mplx:MarkWestMembermplx:FixedRateSeniorNotesMember2020-12-310001552000mplx:ANDXLPMembermplx:FixedRateSeniorNotesMember2021-09-300001552000mplx:ANDXLPMembermplx:FixedRateSeniorNotesMember2020-12-310001552000mplx:MarathonPipeLineLlcMembermplx:FinanceLeaseMember2021-09-300001552000mplx:MarathonPipeLineLlcMembermplx:FinanceLeaseMember2020-12-310001552000mplx:MPLXRevolvingCreditFacilitydueJuly2024Member2019-07-300001552000mplx:MPLXRevolvingCreditFacilitydueJuly2024Membermplx:MPLXLPMember2021-01-012021-09-300001552000mplx:MPLXRevolvingCreditFacilitydueJuly2024Membermplx:MPLXLPMember2021-09-300001552000mplx:VariableRateSeniorNotesMembermplx:MPLXLPMember2021-09-030001552000mplx:VariableRateSeniorNotesMembermplx:FloatingRateSeniorNotesDueSeptember2022Member2021-01-012021-09-300001552000srt:MinimumMembermplx:FixedRateSeniorNotesMember2021-09-300001552000srt:MaximumMembermplx:FixedRateSeniorNotesMember2021-09-300001552000mplx:SeniorNotesDueJanuary2025Membermplx:FixedRateSeniorNotesMember2021-01-150001552000mplx:SeniorNotesDueJanuary2025Membermplx:FixedRateSeniorNotesMember2021-09-300001552000mplx:SeniorNotesDueJanuary2025Membermplx:ANDXLPMembermplx:FixedRateSeniorNotesMember2021-01-150001552000mplx:SeniorNotesDueJanuary2025Membermplx:FixedRateSeniorNotesMember2021-01-012021-09-300001552000us-gaap:ServiceMembermplx:LogisticsandStorageMember2021-07-012021-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ServiceMember2021-07-012021-09-300001552000mplx:LogisticsandStorageMemberus-gaap:ServiceOtherMember2021-07-012021-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ServiceOtherMember2021-07-012021-09-300001552000mplx:LogisticsandStorageMemberus-gaap:ProductMember2021-07-012021-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ProductMember2021-07-012021-09-300001552000us-gaap:ServiceMembermplx:LogisticsandStorageMember2020-07-012020-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ServiceMember2020-07-012020-09-300001552000mplx:LogisticsandStorageMemberus-gaap:ServiceOtherMember2020-07-012020-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ServiceOtherMember2020-07-012020-09-300001552000mplx:LogisticsandStorageMemberus-gaap:ProductMember2020-07-012020-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ProductMember2020-07-012020-09-300001552000us-gaap:ServiceMembermplx:LogisticsandStorageMember2021-01-012021-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ServiceMember2021-01-012021-09-300001552000mplx:LogisticsandStorageMemberus-gaap:ServiceOtherMember2021-01-012021-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ServiceOtherMember2021-01-012021-09-300001552000mplx:LogisticsandStorageMemberus-gaap:ProductMember2021-01-012021-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ProductMember2021-01-012021-09-300001552000us-gaap:ServiceMembermplx:LogisticsandStorageMember2020-01-012020-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ServiceMember2020-01-012020-09-300001552000mplx:LogisticsandStorageMemberus-gaap:ServiceOtherMember2020-01-012020-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ServiceOtherMember2020-01-012020-09-300001552000mplx:LogisticsandStorageMemberus-gaap:ProductMember2020-01-012020-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ProductMember2020-01-012020-09-300001552000us-gaap:AccountingStandardsUpdate201409Member2020-12-310001552000us-gaap:AccountingStandardsUpdate201409Member2021-01-012021-09-300001552000us-gaap:AccountingStandardsUpdate201409Member2021-09-300001552000us-gaap:AccountingStandardsUpdate201409Member2019-12-310001552000us-gaap:AccountingStandardsUpdate201409Member2020-01-012020-09-300001552000us-gaap:AccountingStandardsUpdate201409Member2020-09-3000015520002043-10-012021-09-3000015520002021-10-012021-09-3000015520002022-01-012021-09-3000015520002023-01-012021-09-3000015520002024-01-012021-09-3000015520002025-01-012021-09-300001552000us-gaap:ReclassificationOtherMember2021-06-300001552000mplx:MarathonPetroleumCorporationMemberus-gaap:ReclassificationOtherMember2021-06-300001552000mplx:MarathonPetroleumCorporationMemberus-gaap:ReclassificationOtherMember2021-04-012021-06-300001552000mplx:RefiningLogisticsMemberus-gaap:ReclassificationOtherMember2020-03-310001552000mplx:MarathonPetroleumCorporationMembermplx:RefiningLogisticsMemberus-gaap:ReclassificationOtherMember2020-03-310001552000mplx:MarathonPetroleumCorporationMembermplx:RefiningLogisticsMemberus-gaap:ReclassificationOtherMember2020-01-012020-03-310001552000us-gaap:ReclassificationOtherMember2021-09-300001552000mplx:MarathonPetroleumCorporationMembermplx:EnvironmentalLossContingencyMember2020-12-310001552000mplx:MarathonPetroleumCorporationMembermplx:EnvironmentalLossContingencyMember2021-09-300001552000us-gaap:GuaranteeTypeOtherMember2021-09-3000015520002020-10-012020-12-31
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
 _____________________________________________
FORM 10-Q
 ____________________________________________
(Mark One)
QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the quarterly period ended September 30, 2021
OR
TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the transition period from                      to                     
Commission file number 001-35714
_____________________________________________ 
MPLX LP
(Exact name of registrant as specified in its charter)
 _____________________________________________
Delaware27-0005456
(State or other jurisdiction of
incorporation or organization)
 (I.R.S. Employer
Identification No.)
200 E. Hardin Street,Findlay,Ohio 45840
(Address of principal executive offices)(Zip code)
(419) 421-2414
(Registrant’s telephone number, including area code)
 _____________________________________________
Securities Registered pursuant to Section 12(b) of the Act
Title of each class Trading symbol(s)Name of each exchange on which registered
Common Units Representing Limited Partnership InterestsMPLXNew York Stock Exchange
Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes  x     No  ¨

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files.) Yes  x    No  ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.
Large accelerated filerxAccelerated filer
Non-accelerated filerSmaller reporting company
Emerging growth company

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ¨

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act) Yes      No  x

MPLX LP had 1,019,863,638 common units outstanding at October 29, 2021.


Table of Contents

Unless the context otherwise requires, references in this report to “MPLX LP,” “MPLX,” “the Partnership,” “we,” “our,” “us,” or like terms refer to MPLX LP and its subsidiaries. Additionally, throughout this Quarterly Report on Form 10-Q, we have used terms in our discussion of the business and operating results that have been defined in our Glossary of Terms.

1


Glossary of Terms

The abbreviations, acronyms and industry technology used in this report are defined as follows.
ASCAccounting Standards Codification
ASUAccounting Standards Update
BarrelOne stock tank barrel, or 42 U.S. gallons of liquid volume, used in reference to crude oil or other liquid hydrocarbons
Bcf/dOne billion cubic feet per day
BtuOne British thermal unit, an energy measurement
CondensateA natural gas liquid with a low vapor pressure mainly composed of propane, butane, pentane and heavier hydrocarbon fractions
DCF (a non-GAAP financial measure)Distributable Cash Flow
EBITDA (a non-GAAP financial measure)Earnings Before Interest, Taxes, Depreciation and Amortization
FASBFinancial Accounting Standards Board
GAAPAccounting principles generally accepted in the United States of America
G&PGathering and Processing segment
LIBORLondon Interbank Offered Rate
L&SLogistics and Storage segment
mbpdThousand barrels per day
MMBtuOne million British thermal units, an energy measurement
MMcf/dOne million cubic feet of natural gas per day
NGLNatural gas liquids, such as ethane, propane, butanes and natural gasoline
NYSENew York Stock Exchange
Realized derivative gain/lossThe gain or loss recognized when a derivative matures or is settled
SECU.S. Securities and Exchange Commission
Unrealized derivative gain/lossThe gain or loss recognized on a derivative due to changes in fair value prior to the instrument maturing or settling
VIEVariable interest entity
Wholesale ExchangeThe transfer to MPC of the Western wholesale distribution business, which MPLX acquired as a result of its acquisition of ANDX, on July 31, 2020.

2


Part I—Financial Information

Item 1. Financial Statements
MPLX LP
Consolidated Statements of Income (Unaudited)
Three Months Ended 
September 30,
Nine Months Ended 
September 30,
(In millions, except per unit data)2021202020212020
Revenues and other income:
Service revenue$600 $604 $1,767 $1,779 
Service revenue - related parties902 909 2,681 2,694 
Service revenue - product related82 41 235 102 
Rental income88 102 286 296 
Rental income - related parties164 241 574 712 
Product sales448 165 1,034 454 
Product sales - related parties26 37 99 100 
Sales-type lease revenue - related parties132 38 305 114 
Income/(loss) from equity method investments(1)
92 83 228 (1,012)
Other income (loss)(2)2 2 5 
Other income - related parties27 25 82 76 
Total revenues and other income2,559 2,247 7,293 5,320 
Costs and expenses:
Cost of revenues (excludes items below)298 323 864 1,006 
Purchased product costs421 152 1,035 374 
Rental cost of sales33 33 97 101 
Rental cost of sales - related parties24 32 86 119 
Purchases - related parties307 297 902 853 
Depreciation and amortization324 346 971 992 
Impairment expense  42 2,165 
General and administrative expenses94 96 267 289 
Restructuring expenses 36  36 
Other taxes27 33 93 94 
Total costs and expenses1,528 1,348 4,357 6,029 
Income/(loss) from operations1,031 899 2,936 (709)
Related party interest and other financial costs2  4 4 
Interest expense (net of amounts capitalized of $2 million, $8 million, $12 million and $31 million respectively)
197 207 590 624 
Other financial costs21 17 67 49 
Income/(loss) before income taxes811 675 2,275 (1,386)
Provision for income taxes 1 1 1 
Net income/(loss)811 674 2,274 (1,387)
Less: Net income attributable to noncontrolling interests9 9 27 24 
Net income/(loss) attributable to MPLX LP802 665 2,247 (1,411)
Less: Series A preferred unitholders interest in net income38 20 79 61 
Less: Series B preferred unitholders interest in net income10 10 31 31 
Limited partners’ interest in net income/(loss) attributable to MPLX LP$754 $635 $2,137 $(1,503)
Per Unit Data (See Note 7)
Net income/(loss) attributable to MPLX LP per limited partner unit:
Common - basic$0.74 $0.61 $2.07 $(1.43)
Common - diluted$0.74 $0.61 $2.07 $(1.43)
Weighted average limited partner units outstanding:
Common - basic1,024 1,046 1,030 1,054 
Common - diluted1,025 1,047 1,030 1,054 

(1)     The nine months ended September 30, 2021 and September 30, 2020 include $6 million and $1,264 million of impairment expense, respectively.

The accompanying notes are an integral part of these consolidated financial statements.
3


MPLX LP
Consolidated Statements of Comprehensive Income (Unaudited)
Three Months Ended 
September 30,
Nine Months Ended 
September 30,
(In millions)2021202020212020
Net income/(loss)$811 $674 $2,274 $(1,387)
Other comprehensive income/(loss), net of tax:
Remeasurements of pension and other postretirement benefits related to equity method investments, net of tax  (2)(1)
Comprehensive income/(loss)811 674 2,272 (1,388)
Less comprehensive income attributable to:
Noncontrolling interests9 9 27 24 
Comprehensive income/(loss) attributable to MPLX LP$802 $665 $2,245 $(1,412)


The accompanying notes are an integral part of these consolidated financial statements.

4


MPLX LP
Consolidated Balance Sheets (Unaudited)
 
(In millions)September 30, 2021December 31, 2020
Assets
Current assets:
Cash and cash equivalents$39 $15 
Receivables, net617 452 
Current assets - related parties645 677 
Inventories141 118 
Assets held for sale20 188 
Other current assets54 65 
Total current assets1,516 1,515 
Equity method investments4,001 4,036 
Property, plant and equipment, net20,158 21,218 
Intangibles, net864 959 
Goodwill7,657 7,657 
Right of use assets, net282 309 
Noncurrent assets - related parties1,160 672 
Other noncurrent assets61 48 
Total assets35,699 36,414 
Liabilities
Current liabilities:
Accounts payable177 152 
Accrued liabilities332 194 
Current liabilities - related parties1,706 356 
Accrued property, plant and equipment66 84 
Long-term debt due within one year1 764 
Accrued interest payable188 222 
Operating lease liabilities61 63 
Liabilities held for sale 101 
Other current liabilities190 150 
Total current liabilities2,721 2,086 
Long-term deferred revenue366 314 
Long-term liabilities - related parties297 283 
Long-term debt18,253 19,375 
Deferred income taxes11 12 
Long-term operating lease liabilities220 244 
Deferred credits and other liabilities155 115 
Total liabilities22,023 22,429 
Commitments and contingencies (see Note 19)
Series A preferred units986 968 
Equity
Common unitholders - public (374 million and 391 million units issued and outstanding)
8,919 9,384 
Common unitholders - MPC (647 million and 647 million units issued and outstanding)
2,944 2,792 
Series B preferred units (.6 million and .6 million units issued and outstanding)
601 611 
Accumulated other comprehensive loss(17)(15)
Total MPLX LP partners’ capital12,447 12,772 
Noncontrolling interests243 245 
Total equity12,690 13,017 
Total liabilities, preferred units and equity$35,699 $36,414 

The accompanying notes are an integral part of these consolidated financial statements.
5


MPLX LP
Consolidated Statements of Cash Flows (Unaudited)
Nine Months Ended 
September 30,
(In millions)20212020
Increase/(decrease) in cash, cash equivalents and restricted cash
Operating activities:
Net income/(loss)$2,274 $(1,387)
Adjustments to reconcile net income/(loss) to net cash provided by operating activities:
Amortization of deferred financing costs53 44 
Depreciation and amortization971 992 
Impairment expense42 2,165 
Deferred income taxes(1)(1)
Loss on disposal of assets4 1 
(Income)/loss from equity method investments(1)
(228)1,012 
Distributions from unconsolidated affiliates361 350 
Changes in:
Current receivables(162)69 
Inventories(22)(8)
Fair value of derivatives41 1 
Current accounts payable and accrued liabilities166 (27)
Current assets/current liabilities - related parties94 36 
Right of use assets/operating lease liabilities2 (2)
Deferred revenue65 85 
All other, net11 6 
Net cash provided by operating activities3,671 3,336 
Investing activities:
Additions to property, plant and equipment(374)(982)
Disposal of assets77 54 
Investments in unconsolidated affiliates(116)(244)
Distributions from unconsolidated affiliates - return of capital36 112 
Net cash used in investing activities(377)(1,060)
Financing activities:
Long-term debt - borrowings3,000 5,990 
      - repayments(4,946)(5,372)
Related party debt - borrowings6,571 4,870 
        - repayments(5,201)(5,464)
Debt issuance costs (23)
Unit repurchases(465) 
Distributions to noncontrolling interests(29)(26)
Distributions to Series A preferred unitholders(61)(61)
Distributions to Series B preferred unitholders(41)(41)
Distributions to unitholders and general partner(2,126)(2,162)
Contributions from MPC31 34 
All other, net(3)(8)
Net cash used in financing activities(3,270)(2,263)
Net increase in cash, cash equivalents and restricted cash24 13 
Cash, cash equivalents and restricted cash at beginning of period15 15 
Cash, cash equivalents and restricted cash at end of period$39 $28 

(1)     The nine months ended September 30, 2021 and September 30, 2020 include $6 million and $1,264 million of impairment expense, respectively.

The accompanying notes are an integral part of these consolidated financial statements.
6


MPLX LP
Consolidated Statements of Equity (Unaudited)

 Partnership  
(In millions)Common
Unit-holders
Public
Common
Unit-holder
MPC
Series B Preferred Unit-holdersAccumulated Other Comprehensive LossNon-controlling
Interests
Total
Balance at December 31, 2019$10,800 $4,968 $611 $(15)$249 $16,613 
Net (loss)/income (excludes amounts attributable to Series A preferred units)(1,022)(1,733)11  8 (2,736)
Distributions to:
Unitholders(271)(446)(21)  (738)
Noncontrolling interests    (9)(9)
Contributions from:
MPC 225    225 
Other2   (1) 1 
Balance at March 31, 20209,509 3,014 601 (16)248 13,356 
Net income (excludes amounts attributable to Series A preferred units)229 388 10  7 634 
Distributions to:
Unitholders(270)(458)   (728)
Noncontrolling interests    (8)(8)
Contributions from:
MPC 6    6 
Other1 1    2 
Balance at June 30, 20209,469 2,951 611 (16)247 13,262 
Net income (excludes amounts attributable to Series A preferred units)236 399 10  9 654 
Distributions to:
Unitholders(271)(445)(20)  (736)
Noncontrolling interests    (9)(9)
Contributions from:
MPC 13    13 
Wholesale Exchange (90)   (90)
Other2 (1)   1 
Balance at September 30, 2020$9,436 $2,827 $601 $(16)$247 $13,095 
The accompanying notes are an integral part of these consolidated financial statements.
7


 Partnership  
(In millions)Common
Unit-holders
Public
Common
Unit-holder
MPC
Series B Preferred Unit-holdersAccumulated Other Comprehensive LossNon-controlling
Interests
Total
Balance at December 31, 2020$9,384 $2,792 $611 $(15)$245 $13,017 
Net income (excludes amounts attributable to Series A preferred units)266 443 11  9 729 
Unit Repurchases(155)    (155)
Distributions to:
Unitholders(269)(445)(21)  (735)
Noncontrolling interests    (10)(10)
Contributions from:
MPC 7    7 
Other (1) (2) (3)
Balance at March 31, 20219,226 2,796 601 (17)244 12,850 
Net income (excludes amounts attributable to Series A preferred units)251 423 10  9 693 
Unit Repurchases(155)