2023Q30001552000--12-31falseP5YP5Yhttp://fasb.org/us-gaap/2023#ProfitLosshttp://fasb.org/us-gaap/2023#ProfitLosshttp://fasb.org/us-gaap/2023#ProfitLosshttp://fasb.org/us-gaap/2023#ProfitLoss31111http://fasb.org/us-gaap/2023#DeferredCreditsAndOtherLiabilitiesNoncurrent http://fasb.org/us-gaap/2023#OtherLiabilitiesCurrenthttp://fasb.org/us-gaap/2023#DeferredCreditsAndOtherLiabilitiesNoncurrent http://fasb.org/us-gaap/2023#OtherLiabilitiesCurrent00015520002023-01-012023-09-3000015520002023-10-27xbrli:shares0001552000us-gaap:ServiceMember2023-07-012023-09-30iso4217:USD0001552000us-gaap:ServiceMember2022-07-012022-09-300001552000us-gaap:ServiceMember2023-01-012023-09-300001552000us-gaap:ServiceMember2022-01-012022-09-300001552000us-gaap:ServiceOtherMember2023-07-012023-09-300001552000us-gaap:ServiceOtherMember2022-07-012022-09-300001552000us-gaap:ServiceOtherMember2023-01-012023-09-300001552000us-gaap:ServiceOtherMember2022-01-012022-09-300001552000us-gaap:NonrelatedPartyMember2023-07-012023-09-300001552000us-gaap:NonrelatedPartyMember2022-07-012022-09-300001552000us-gaap:NonrelatedPartyMember2023-01-012023-09-300001552000us-gaap:NonrelatedPartyMember2022-01-012022-09-300001552000us-gaap:RelatedPartyMember2023-07-012023-09-300001552000us-gaap:RelatedPartyMember2022-07-012022-09-300001552000us-gaap:RelatedPartyMember2023-01-012023-09-300001552000us-gaap:RelatedPartyMember2022-01-012022-09-300001552000us-gaap:ProductMember2023-07-012023-09-300001552000us-gaap:ProductMember2022-07-012022-09-300001552000us-gaap:ProductMember2023-01-012023-09-300001552000us-gaap:ProductMember2022-01-012022-09-3000015520002023-07-012023-09-3000015520002022-07-012022-09-3000015520002022-01-012022-09-300001552000us-gaap:OilAndGasRefiningAndMarketingMember2023-07-012023-09-300001552000us-gaap:OilAndGasRefiningAndMarketingMember2022-07-012022-09-300001552000us-gaap:OilAndGasRefiningAndMarketingMember2023-01-012023-09-300001552000us-gaap:OilAndGasRefiningAndMarketingMember2022-01-012022-09-300001552000us-gaap:NaturalGasMidstreamMember2023-07-012023-09-300001552000us-gaap:NaturalGasMidstreamMember2022-07-012022-09-300001552000us-gaap:NaturalGasMidstreamMember2023-01-012023-09-300001552000us-gaap:NaturalGasMidstreamMember2022-01-012022-09-300001552000srt:AffiliatedEntityMember2023-07-012023-09-300001552000srt:AffiliatedEntityMember2022-07-012022-09-300001552000srt:AffiliatedEntityMember2023-01-012023-09-300001552000srt:AffiliatedEntityMember2022-01-012022-09-300001552000us-gaap:SeriesAPreferredStockMember2023-07-012023-09-300001552000us-gaap:SeriesAPreferredStockMember2022-07-012022-09-300001552000us-gaap:SeriesAPreferredStockMember2023-01-012023-09-300001552000us-gaap:SeriesAPreferredStockMember2022-01-012022-09-300001552000us-gaap:SeriesBPreferredStockMember2023-07-012023-09-300001552000us-gaap:SeriesBPreferredStockMember2022-07-012022-09-300001552000us-gaap:SeriesBPreferredStockMember2023-01-012023-09-300001552000us-gaap:SeriesBPreferredStockMember2022-01-012022-09-30iso4217:USDxbrli:shares00015520002023-09-3000015520002022-12-310001552000us-gaap:RelatedPartyMember2023-09-300001552000us-gaap:RelatedPartyMember2022-12-310001552000us-gaap:NonrelatedPartyMember2023-09-300001552000us-gaap:NonrelatedPartyMember2022-12-310001552000us-gaap:SeriesAPreferredStockMember2023-09-300001552000us-gaap:SeriesAPreferredStockMember2022-12-310001552000us-gaap:NonrelatedPartyMemberus-gaap:CommonStockMember2023-09-300001552000us-gaap:NonrelatedPartyMemberus-gaap:CommonStockMember2022-12-310001552000us-gaap:RelatedPartyMemberus-gaap:CommonStockMember2023-09-300001552000us-gaap:RelatedPartyMemberus-gaap:CommonStockMember2022-12-310001552000us-gaap:SeriesBPreferredStockMember2023-09-300001552000us-gaap:SeriesBPreferredStockMember2022-12-310001552000us-gaap:RevolvingCreditFacilityMember2023-01-012023-09-300001552000us-gaap:RevolvingCreditFacilityMember2022-01-012022-09-3000015520002021-12-3100015520002022-09-300001552000us-gaap:CommonStockMember2022-12-310001552000mplx:CommonStock_RelatedPartyInterestMember2022-12-310001552000us-gaap:PreferredStockMember2022-12-310001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2022-12-310001552000us-gaap:NoncontrollingInterestMember2022-12-310001552000mplx:TemporaryEquityMember2022-12-310001552000us-gaap:CommonStockMember2023-01-012023-03-310001552000mplx:CommonStock_RelatedPartyInterestMember2023-01-012023-03-310001552000us-gaap:PreferredStockMember2023-01-012023-03-310001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2023-01-012023-03-310001552000us-gaap:NoncontrollingInterestMember2023-01-012023-03-3100015520002023-01-012023-03-310001552000mplx:TemporaryEquityMember2023-01-012023-03-310001552000us-gaap:CommonStockMember2023-03-310001552000mplx:CommonStock_RelatedPartyInterestMember2023-03-310001552000us-gaap:PreferredStockMember2023-03-310001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2023-03-310001552000us-gaap:NoncontrollingInterestMember2023-03-3100015520002023-03-310001552000mplx:TemporaryEquityMember2023-03-310001552000us-gaap:CommonStockMember2023-04-012023-06-300001552000mplx:CommonStock_RelatedPartyInterestMember2023-04-012023-06-300001552000us-gaap:PreferredStockMember2023-04-012023-06-300001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2023-04-012023-06-300001552000us-gaap:NoncontrollingInterestMember2023-04-012023-06-3000015520002023-04-012023-06-300001552000mplx:TemporaryEquityMember2023-04-012023-06-300001552000us-gaap:CommonStockMember2023-06-300001552000mplx:CommonStock_RelatedPartyInterestMember2023-06-300001552000us-gaap:PreferredStockMember2023-06-300001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2023-06-300001552000us-gaap:NoncontrollingInterestMember2023-06-3000015520002023-06-300001552000mplx:TemporaryEquityMember2023-06-300001552000us-gaap:CommonStockMember2023-07-012023-09-300001552000mplx:CommonStock_RelatedPartyInterestMember2023-07-012023-09-300001552000us-gaap:PreferredStockMember2023-07-012023-09-300001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2023-07-012023-09-300001552000us-gaap:NoncontrollingInterestMember2023-07-012023-09-300001552000mplx:TemporaryEquityMember2023-07-012023-09-300001552000us-gaap:CommonStockMember2023-09-300001552000mplx:CommonStock_RelatedPartyInterestMember2023-09-300001552000us-gaap:PreferredStockMember2023-09-300001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2023-09-300001552000us-gaap:NoncontrollingInterestMember2023-09-300001552000mplx:TemporaryEquityMember2023-09-300001552000us-gaap:CommonStockMember2021-12-310001552000mplx:CommonStock_RelatedPartyInterestMember2021-12-310001552000us-gaap:PreferredStockMember2021-12-310001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2021-12-310001552000us-gaap:NoncontrollingInterestMember2021-12-310001552000mplx:TemporaryEquityMember2021-12-310001552000us-gaap:CommonStockMember2022-01-012022-03-310001552000mplx:CommonStock_RelatedPartyInterestMember2022-01-012022-03-310001552000us-gaap:PreferredStockMember2022-01-012022-03-310001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2022-01-012022-03-310001552000us-gaap:NoncontrollingInterestMember2022-01-012022-03-3100015520002022-01-012022-03-310001552000mplx:TemporaryEquityMember2022-01-012022-03-310001552000us-gaap:CommonStockMember2022-03-310001552000mplx:CommonStock_RelatedPartyInterestMember2022-03-310001552000us-gaap:PreferredStockMember2022-03-310001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2022-03-310001552000us-gaap:NoncontrollingInterestMember2022-03-3100015520002022-03-310001552000mplx:TemporaryEquityMember2022-03-310001552000us-gaap:CommonStockMember2022-04-012022-06-300001552000mplx:CommonStock_RelatedPartyInterestMember2022-04-012022-06-300001552000us-gaap:PreferredStockMember2022-04-012022-06-300001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2022-04-012022-06-300001552000us-gaap:NoncontrollingInterestMember2022-04-012022-06-3000015520002022-04-012022-06-300001552000mplx:TemporaryEquityMember2022-04-012022-06-300001552000us-gaap:CommonStockMember2022-06-300001552000mplx:CommonStock_RelatedPartyInterestMember2022-06-300001552000us-gaap:PreferredStockMember2022-06-300001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2022-06-300001552000us-gaap:NoncontrollingInterestMember2022-06-3000015520002022-06-300001552000mplx:TemporaryEquityMember2022-06-300001552000us-gaap:CommonStockMember2022-07-012022-09-300001552000mplx:CommonStock_RelatedPartyInterestMember2022-07-012022-09-300001552000us-gaap:PreferredStockMember2022-07-012022-09-300001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2022-07-012022-09-300001552000us-gaap:NoncontrollingInterestMember2022-07-012022-09-300001552000mplx:TemporaryEquityMember2022-07-012022-09-300001552000us-gaap:CommonStockMember2022-09-300001552000mplx:CommonStock_RelatedPartyInterestMember2022-09-300001552000us-gaap:PreferredStockMember2022-09-300001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2022-09-300001552000us-gaap:NoncontrollingInterestMember2022-09-300001552000mplx:TemporaryEquityMember2022-09-30xbrli:pure0001552000mplx:LogisticsandStorageMembermplx:AndeavorLogisticsRioPipelineMember2023-09-300001552000mplx:LogisticsandStorageMembermplx:AndeavorLogisticsRioPipelineMember2022-12-310001552000mplx:LogisticsandStorageMembermplx:IllinoisExtensionPipelineCompanyLLCMember2023-09-300001552000mplx:LogisticsandStorageMembermplx:IllinoisExtensionPipelineCompanyLLCMember2022-12-310001552000mplx:LogisticsandStorageMembermplx:LoopLlcMember2023-09-300001552000mplx:LogisticsandStorageMembermplx:LoopLlcMember2022-12-310001552000mplx:LogisticsandStorageMembermplx:MarEnBakkenCompanyLLCMember2023-09-300001552000mplx:LogisticsandStorageMembermplx:MarEnBakkenCompanyLLCMember2022-12-310001552000mplx:LogisticsandStorageMembermplx:MinnesotaPipeLineCompanyLLCMember2023-09-300001552000mplx:LogisticsandStorageMembermplx:MinnesotaPipeLineCompanyLLCMember2022-12-310001552000mplx:LogisticsandStorageMembermplx:WhistlerPipelineLLCMember2023-09-300001552000mplx:LogisticsandStorageMembermplx:WhistlerPipelineLLCMember2022-12-310001552000mplx:LogisticsandStorageMembermplx:OtherVIEsandNonVIEsMember2023-09-300001552000mplx:LogisticsandStorageMembermplx:OtherVIEsandNonVIEsMember2022-12-310001552000mplx:LogisticsandStorageMember2023-09-300001552000mplx:LogisticsandStorageMember2022-12-310001552000mplx:GatheringandProcessingMembermplx:CentrahomaProcessingLLCMember2023-09-300001552000mplx:GatheringandProcessingMembermplx:CentrahomaProcessingLLCMember2022-12-310001552000mplx:GatheringandProcessingMembermplx:MarkWestEMGJeffersonDryGasGatheringCompanyL.L.C.Member2023-09-300001552000mplx:GatheringandProcessingMembermplx:MarkWestEMGJeffersonDryGasGatheringCompanyL.L.C.Member2022-12-310001552000mplx:MarkWestTornadoGPLLCMembermplx:GatheringandProcessingMember2023-09-300001552000mplx:MarkWestTornadoGPLLCMembermplx:GatheringandProcessingMember2022-12-310001552000mplx:MarkWestUticaEMGMembermplx:GatheringandProcessingMember2023-09-300001552000mplx:MarkWestUticaEMGMembermplx:GatheringandProcessingMember2022-12-310001552000mplx:RendezvousGasServicesL.L.C.Membermplx:GatheringandProcessingMember2023-09-300001552000mplx:RendezvousGasServicesL.L.C.Membermplx:GatheringandProcessingMember2022-12-310001552000mplx:SherwoodMidstreamHoldingsMembermplx:GatheringandProcessingMembermplx:DirectOwnershipInterestMember2023-09-300001552000mplx:SherwoodMidstreamHoldingsMembermplx:GatheringandProcessingMember2023-09-300001552000mplx:SherwoodMidstreamHoldingsMembermplx:GatheringandProcessingMember2022-12-310001552000mplx:SherwoodMidstreamLLCMembermplx:GatheringandProcessingMember2023-09-300001552000mplx:SherwoodMidstreamLLCMembermplx:GatheringandProcessingMember2022-12-310001552000mplx:GatheringandProcessingMembermplx:OtherVIEsandNonVIEsMember2023-09-300001552000mplx:GatheringandProcessingMembermplx:OtherVIEsandNonVIEsMember2022-12-310001552000mplx:GatheringandProcessingMember2023-09-300001552000mplx:GatheringandProcessingMember2022-12-310001552000mplx:LogisticsandStorageMembermplx:IndirectOwnershipInterestMembermplx:BakkenPipelineSystemMember2023-09-300001552000us-gaap:RevolvingCreditFacilityMemberus-gaap:RelatedPartyMember2023-09-300001552000us-gaap:RevolvingCreditFacilityMemberus-gaap:RelatedPartyMember2023-01-012023-09-300001552000us-gaap:AssetUnderConstructionMemberus-gaap:RelatedPartyMember2023-07-012023-09-300001552000us-gaap:AssetUnderConstructionMemberus-gaap:RelatedPartyMember2023-01-012023-09-300001552000us-gaap:AssetUnderConstructionMemberus-gaap:RelatedPartyMember2022-07-012022-09-300001552000us-gaap:AssetUnderConstructionMemberus-gaap:RelatedPartyMember2022-01-012022-09-300001552000us-gaap:RevolvingCreditFacilityMemberus-gaap:RelatedPartyMember2022-12-3100015520002022-08-020001552000us-gaap:SeriesBPreferredStockMember2023-02-152023-02-150001552000us-gaap:SeriesBPreferredStockMember2023-02-150001552000us-gaap:SubsequentEventMember2023-10-242023-10-240001552000us-gaap:SubsequentEventMemberus-gaap:CommonStockMember2023-11-132023-11-130001552000us-gaap:SubsequentEventMemberus-gaap:CommonStockMember2023-11-032023-11-030001552000us-gaap:CommonStockMember2023-07-012023-09-300001552000us-gaap:CommonStockMember2022-07-012022-09-300001552000us-gaap:CommonStockMember2023-01-012023-09-300001552000us-gaap:CommonStockMember2022-01-012022-09-300001552000mplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMemberus-gaap:ServiceMember2023-07-012023-09-300001552000mplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMemberus-gaap:ServiceMember2022-07-012022-09-300001552000mplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMemberus-gaap:ServiceMember2023-01-012023-09-300001552000mplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMemberus-gaap:ServiceMember2022-01-012022-09-300001552000mplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMember2023-07-012023-09-300001552000mplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMember2022-07-012022-09-300001552000mplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMember2023-01-012023-09-300001552000mplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMember2022-01-012022-09-300001552000us-gaap:ProductMembermplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMember2023-07-012023-09-300001552000us-gaap:ProductMembermplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMember2022-07-012022-09-300001552000us-gaap:ProductMembermplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMember2023-01-012023-09-300001552000us-gaap:ProductMembermplx:LogisticsandStorageMemberus-gaap:OperatingSegmentsMember2022-01-012022-09-300001552000us-gaap:OperatingSegmentsMembermplx:GatheringandProcessingMemberus-gaap:ServiceMember2023-07-012023-09-300001552000us-gaap:OperatingSegmentsMembermplx:GatheringandProcessingMemberus-gaap:ServiceMember2022-07-012022-09-300001552000us-gaap:OperatingSegmentsMembermplx:GatheringandProcessingMemberus-gaap:ServiceMember2023-01-012023-09-300001552000us-gaap:OperatingSegmentsMembermplx:GatheringandProcessingMemberus-gaap:ServiceMember2022-01-012022-09-300001552000us-gaap:OperatingSegmentsMembermplx:GatheringandProcessingMember2023-07-012023-09-300001552000us-gaap:OperatingSegmentsMembermplx:GatheringandProcessingMember2022-07-012022-09-300001552000us-gaap:OperatingSegmentsMembermplx:GatheringandProcessingMember2023-01-012023-09-300001552000us-gaap:OperatingSegmentsMembermplx:GatheringandProcessingMember2022-01-012022-09-300001552000us-gaap:ProductMemberus-gaap:OperatingSegmentsMembermplx:GatheringandProcessingMember2023-07-012023-09-300001552000us-gaap:ProductMemberus-gaap:OperatingSegmentsMembermplx:GatheringandProcessingMember2022-07-012022-09-300001552000us-gaap:ProductMemberus-gaap:OperatingSegmentsMembermplx:GatheringandProcessingMember2023-01-012023-09-300001552000us-gaap:ProductMemberus-gaap:OperatingSegmentsMembermplx:GatheringandProcessingMember2022-01-012022-09-300001552000mplx:LogisticsandStorageMembermplx:ThirdPartyMember2023-07-012023-09-300001552000mplx:LogisticsandStorageMembermplx:ThirdPartyMember2023-01-012023-09-300001552000mplx:LogisticsandStorageMembermplx:ThirdPartyMember2022-07-012022-09-300001552000mplx:LogisticsandStorageMembermplx:ThirdPartyMember2022-01-012022-09-300001552000mplx:ThirdPartyMembermplx:GatheringandProcessingMember2023-07-012023-09-300001552000mplx:ThirdPartyMembermplx:GatheringandProcessingMember2023-01-012023-09-300001552000mplx:ThirdPartyMembermplx:GatheringandProcessingMember2022-07-012022-09-300001552000mplx:ThirdPartyMembermplx:GatheringandProcessingMember2022-01-012022-09-300001552000us-gaap:OperatingSegmentsMember2023-07-012023-09-300001552000us-gaap:OperatingSegmentsMember2022-07-012022-09-300001552000us-gaap:OperatingSegmentsMember2023-01-012023-09-300001552000us-gaap:OperatingSegmentsMember2022-01-012022-09-300001552000us-gaap:MaterialReconcilingItemsMember2023-07-012023-09-300001552000us-gaap:MaterialReconcilingItemsMember2022-07-012022-09-300001552000us-gaap:MaterialReconcilingItemsMember2023-01-012023-09-300001552000us-gaap:MaterialReconcilingItemsMember2022-01-012022-09-300001552000mplx:LogisticsandStorageMember2023-07-012023-09-300001552000mplx:LogisticsandStorageMember2023-01-012023-09-300001552000mplx:LogisticsandStorageMember2022-07-012022-09-300001552000mplx:LogisticsandStorageMember2022-01-012022-09-300001552000mplx:GatheringandProcessingMember2023-07-012023-09-300001552000mplx:GatheringandProcessingMember2023-01-012023-09-300001552000mplx:GatheringandProcessingMember2022-07-012022-09-300001552000mplx:GatheringandProcessingMember2022-01-012022-09-300001552000us-gaap:CommodityContractMemberus-gaap:FairValueInputsLevel2Memberus-gaap:OtherCurrentAssetsMember2023-09-300001552000us-gaap:OtherCurrentLiabilitiesMemberus-gaap:CommodityContractMemberus-gaap:FairValueInputsLevel2Member2023-09-300001552000us-gaap:CommodityContractMemberus-gaap:FairValueInputsLevel2Memberus-gaap:OtherCurrentAssetsMember2022-12-310001552000us-gaap:OtherCurrentLiabilitiesMemberus-gaap:CommodityContractMemberus-gaap:FairValueInputsLevel2Member2022-12-310001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:FairValueInputsLevel3Memberus-gaap:OtherCurrentAssetsMember2023-09-300001552000us-gaap:OtherCurrentLiabilitiesMemberus-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:FairValueInputsLevel3Member2023-09-300001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:FairValueInputsLevel3Memberus-gaap:OtherCurrentAssetsMember2022-12-310001552000us-gaap:OtherCurrentLiabilitiesMemberus-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:FairValueInputsLevel3Member2022-12-310001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:FairValueInputsLevel3Memberus-gaap:OtherNoncurrentAssetsMember2023-09-300001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:OtherNoncurrentLiabilitiesMemberus-gaap:FairValueInputsLevel3Member2023-09-300001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:FairValueInputsLevel3Memberus-gaap:OtherNoncurrentAssetsMember2022-12-310001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:OtherNoncurrentLiabilitiesMemberus-gaap:FairValueInputsLevel3Member2022-12-310001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:FairValueInputsLevel3Membersrt:MinimumMember2023-09-300001552000srt:MaximumMemberus-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:FairValueInputsLevel3Member2023-09-30iso4217:USDutr:gal0001552000us-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:FairValueInputsLevel3Member2023-01-012023-09-300001552000mplx:NaturalGasMemberus-gaap:EmbeddedDerivativeFinancialInstrumentsMember2023-01-012023-09-300001552000us-gaap:EstimateOfFairValueFairValueDisclosureMember2023-09-300001552000us-gaap:CarryingReportedAmountFairValueDisclosureMember2023-09-300001552000us-gaap:EstimateOfFairValueFairValueDisclosureMember2022-12-310001552000us-gaap:CarryingReportedAmountFairValueDisclosureMember2022-12-310001552000us-gaap:PublicUtilitiesInventoryPropaneMemberus-gaap:OverTheCounterMemberus-gaap:ShortMember2023-09-30utr:gal0001552000mplx:NaturalGasMemberus-gaap:EmbeddedDerivativeFinancialInstrumentsMember2023-09-300001552000us-gaap:FairValueMeasurementsRecurringMemberus-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:FairValueInputsLevel3Member2023-09-300001552000us-gaap:FairValueMeasurementsRecurringMemberus-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:FairValueInputsLevel3Member2022-12-310001552000mplx:ProductSalesMember2023-07-012023-09-300001552000mplx:ProductSalesMember2022-07-012022-09-300001552000mplx:ProductSalesMember2023-01-012023-09-300001552000mplx:ProductSalesMember2022-01-012022-09-300001552000mplx:PurchasedproductcostsMember2023-07-012023-09-300001552000mplx:PurchasedproductcostsMember2022-07-012022-09-300001552000mplx:PurchasedproductcostsMember2023-01-012023-09-300001552000mplx:PurchasedproductcostsMember2022-01-012022-09-300001552000mplx:MPLXLPMember2023-09-300001552000mplx:MPLXLPMember2022-12-310001552000mplx:MarkWestMember2023-09-300001552000mplx:MarkWestMember2022-12-310001552000mplx:ANDXLPMember2023-09-300001552000mplx:ANDXLPMember2022-12-310001552000mplx:MPLXRevolvingCreditFacilityDueJuly2027Member2022-07-070001552000mplx:MPLXRevolvingCreditFacilityDueJuly2027Member2022-07-072022-07-070001552000srt:MinimumMemberus-gaap:SeniorNotesMember2023-09-300001552000srt:MaximumMemberus-gaap:SeniorNotesMember2023-09-300001552000us-gaap:SeniorNotesMembermplx:SeniorNotesDueMarch2033AndMarch2053Member2023-02-090001552000mplx:SeniorNotesDueMarch2033Memberus-gaap:SeniorNotesMember2023-02-090001552000mplx:SeniorNotesDueMarch2053Memberus-gaap:SeniorNotesMember2023-02-090001552000us-gaap:SeniorNotesMembermplx:SeniorNotesDueJuly2023Member2023-01-012023-09-300001552000us-gaap:SeniorNotesMembermplx:SeniorNotesDueJuly2023Member2023-03-130001552000mplx:LogisticsandStorageMemberus-gaap:ServiceMember2023-07-012023-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ServiceMember2023-07-012023-09-300001552000mplx:LogisticsandStorageMemberus-gaap:ServiceOtherMember2023-07-012023-09-300001552000us-gaap:ServiceOtherMembermplx:GatheringandProcessingMember2023-07-012023-09-300001552000us-gaap:ProductMembermplx:LogisticsandStorageMember2023-07-012023-09-300001552000us-gaap:ProductMembermplx:GatheringandProcessingMember2023-07-012023-09-300001552000mplx:LogisticsandStorageMemberus-gaap:ServiceMember2022-07-012022-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ServiceMember2022-07-012022-09-300001552000mplx:LogisticsandStorageMemberus-gaap:ServiceOtherMember2022-07-012022-09-300001552000us-gaap:ServiceOtherMembermplx:GatheringandProcessingMember2022-07-012022-09-300001552000us-gaap:ProductMembermplx:LogisticsandStorageMember2022-07-012022-09-300001552000us-gaap:ProductMembermplx:GatheringandProcessingMember2022-07-012022-09-300001552000mplx:LogisticsandStorageMemberus-gaap:ServiceMember2023-01-012023-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ServiceMember2023-01-012023-09-300001552000mplx:LogisticsandStorageMemberus-gaap:ServiceOtherMember2023-01-012023-09-300001552000us-gaap:ServiceOtherMembermplx:GatheringandProcessingMember2023-01-012023-09-300001552000us-gaap:ProductMembermplx:LogisticsandStorageMember2023-01-012023-09-300001552000us-gaap:ProductMembermplx:GatheringandProcessingMember2023-01-012023-09-300001552000mplx:LogisticsandStorageMemberus-gaap:ServiceMember2022-01-012022-09-300001552000mplx:GatheringandProcessingMemberus-gaap:ServiceMember2022-01-012022-09-300001552000mplx:LogisticsandStorageMemberus-gaap:ServiceOtherMember2022-01-012022-09-300001552000us-gaap:ServiceOtherMembermplx:GatheringandProcessingMember2022-01-012022-09-300001552000us-gaap:ProductMembermplx:LogisticsandStorageMember2022-01-012022-09-300001552000us-gaap:ProductMembermplx:GatheringandProcessingMember2022-01-012022-09-300001552000us-gaap:NonrelatedPartyMember2021-12-310001552000us-gaap:NonrelatedPartyMember2022-09-300001552000us-gaap:RelatedPartyMember2021-12-310001552000us-gaap:RelatedPartyMember2022-09-3000015520002023-10-012023-09-3000015520002024-01-012023-09-3000015520002025-01-012023-09-3000015520002026-01-012023-09-3000015520002027-01-012023-09-3000015520002028-01-012023-09-3000015520002043-10-012023-09-300001552000us-gaap:RelatedPartyMember2022-08-010001552000us-gaap:NonrelatedPartyMember2022-07-3100015520002020-07-012020-07-3100015520002020-12-152020-12-150001552000us-gaap:FinancialGuaranteeMembermplx:BakkenPipelineSystemMemberus-gaap:GuaranteeOfIndebtednessOfOthersMember2023-09-30
Washington, D.C. 20549
(Mark One)
For the quarterly period ended September 30, 2023
For the transition period from                      to                     
Commission file number 001-35714
(Exact name of registrant as specified in its charter)
(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 filerNon-accelerated filer
Smaller 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 1,001,217,044 common units outstanding as of October 27, 2023.

Table of Contents

Unless otherwise stated or the context otherwise indicates, all references in this Form 10-Q to “MPLX LP,” “MPLX,” “the Partnership,” “we,” “our,” “us,” or like terms refer to MPLX LP and its consolidated subsidiaries. References to our sponsor and customer, “MPC,” refer collectively to Marathon Petroleum Corporation and its subsidiaries, other than the Partnership.

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
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
FCF (a non-GAAP financial measure)Free Cash Flow
GAAPAccounting principles generally accepted in the United States of America
G&PGathering and Processing segment
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
SECU.S. Securities and Exchange Commission
SOFRSecured Overnight Financing Rate
VIEVariable interest entity


Part I—Financial Information
Item 1. Financial Statements
Consolidated Statements of Income (Unaudited)
Three Months Ended 
September 30,
Nine Months Ended 
September 30,
(In millions, except per unit data)2023202220232022
Revenues and other income:
Service revenue$641 $627 $1,881 $1,758 
Service revenue - related parties1,038 948 2,962 2,801 
Service revenue - product related75 83 214 324 
Rental income61 75 181 268 
Rental income - related parties207 201 612 564 
Product sales478 617 1,274 1,812 
Product sales - related parties51 46 155 142 
Sales-type lease revenue34 28 101 28 
Sales-type lease revenue - related parties129 118 379 343 
Income from equity method investments159 125 438 335 
Other income7 505 28 494 
Other income - related parties32 28 90 82 
Total revenues and other income2,912 3,401 8,315 8,951 
Costs and expenses:
Cost of revenues (excludes items below)367 371 1,023 981 
Purchased product costs474 540 1,234 1,670 
Rental cost of sales20 22 60 101 
Rental cost of sales - related parties8 10 24 44 
Purchases - related parties442 364 1,160 1,034 
Depreciation and amortization301 302 907 925 
General and administrative expenses102 88 280 248 
Other taxes44 30 102 97 
Total costs and expenses1,758 1,727 4,790 5,100 
Income from operations1,154 1,674 3,525 3,851 
Related-party interest and other financial costs   5 
Interest expense, net of amounts capitalized 223 217 673 627 
Other financial costs, net2 19 28 59 
Income before income taxes929 1,438 2,824 3,160 
Provision for income taxes1 1 2 6 
Net income928 1,437 2,822 3,154 
Less: Net income attributable to noncontrolling interests10 9 28 26 
Net income attributable to MPLX LP918 1,428 2,794 3,128 
Less: Series A preferred unitholders interest in net income25 23 71 65 
Less: Series B preferred unitholders interest in net income 10 5 31 
Limited partners' interest in net income attributable to MPLX LP$893 $1,395 $2,718 $3,032 
Per Unit Data (See Note 6)
Net income attributable to MPLX LP per limited partner unit:
Common - basic$0.89 $1.36 $2.70 $2.97 
Common - diluted$0.89 $1.36 $2.70 $2.97 
Weighted average limited partner units outstanding:
Common - basic1,001 1,010 1,001 1,012 
Common - diluted1,001 1,011 1,001 1,013 

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

Consolidated Statements of Comprehensive Income (Unaudited)
Three Months Ended 
September 30,
Nine Months Ended 
September 30,
(In millions)2023202220232022
Net income$928 $1,437 $2,822 $3,154 
Other comprehensive income, net of tax:
Remeasurements of pension and other postretirement benefits related to equity method investments, net of tax  4 9 
Comprehensive income928 1,437 2,826 3,163 
Less comprehensive income attributable to:
Noncontrolling interests10 9 28 26 
Comprehensive income attributable to MPLX LP$918 $1,428 $2,798 $3,137 

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


Consolidated Balance Sheets (Unaudited)
(In millions)September 30,
December 31,
Cash and cash equivalents$960 $238 
Receivables, net833 737 
Current assets - related parties759 729 
Inventories154 148 
Other current assets30 53 
Total current assets2,736 1,905 
Equity method investments4,099 4,095 
Property, plant and equipment, net18,620 18,848 
Intangibles, net609 705 
Goodwill7,645 7,645 
Right of use assets, net271 283 
Noncurrent assets - related parties1,174 1,225 
Other noncurrent assets966 959 
Total assets36,120 35,665 
Accounts payable132 224 
Accrued liabilities332 269 
Current liabilities - related parties387 343 
Accrued property, plant and equipment140 128 
Long-term debt due within one year1 988 
Accrued interest payable187 237 
Operating lease liabilities48 46 
Other current liabilities172 166 
Total current liabilities1,399 2,401 
Long-term deferred revenue295 219 
Long-term liabilities - related parties343 338 
Long-term debt20,417 18,808 
Deferred income taxes12 13 
Long-term operating lease liabilities219 230 
Other long-term liabilities119 142 
Total liabilities22,804 22,151 
Commitments and contingencies (see Note 15)
Series A preferred units (30 million and 30 million units issued and outstanding)
970 968 
Common unitholders - public (354 million and 354 million units issued and outstanding)
8,533 8,413 
Common unitholders - MPC (647 million and 647 million units issued and outstanding)
3,581 3,293 
Series B preferred units (0 million and 0.6 million units issued and outstanding)
Accumulated other comprehensive loss(4)(8)
Total MPLX LP partners’ capital12,110 12,309 
Noncontrolling interests236 237 
Total equity12,346 12,546 
Total liabilities, preferred units and equity$36,120 $35,665 

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

Consolidated Statements of Cash Flows (Unaudited)
Nine Months Ended 
September 30,
(In millions)20232022
Operating activities:
Net income$2,822 $3,154 
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of deferred financing costs42 55 
Depreciation and amortization907 925 
Deferred income taxes(1)4 
Gain on sales-type leases (509)
(Gain)/loss on disposal of assets(15)23 
Income from equity method investments(438)(335)
Distributions from unconsolidated affiliates526 405 
Change in fair value of derivatives(3)(62)
Changes in:
Accounts payable and accrued liabilities(56)49 
Assets/liabilities - related parties89 52 
Right of use assets/operating lease liabilities4 1 
Deferred revenue65 64 
All other, net12 51 
Net cash provided by operating activities3,908 3,651 
Investing activities:
Additions to property, plant and equipment(662)(535)
Acquisitions, net of cash acquired (28)
Disposal of assets25 74 
Investments in unconsolidated affiliates(90)(198)
Distributions from unconsolidated affiliates - return of capital 11 
Net cash used in investing activities(727)(676)
Financing activities:
Long-term debt borrowings1,589 3,379 
Long-term debt repayments(1,001)(2,202)
Related party debt borrowings 2,824 
Related party debt repayments (4,274)
Debt issuance costs(15)(29)
Unit repurchases (315)
Redemption of Series B preferred units(600) 
Distributions to noncontrolling interests(30)(29)
Distributions to Series A preferred unitholders(69)(63)
Distributions to Series B preferred unitholders(21)(41)
Distributions to unitholders and general partner(2,329)(2,144)
Contributions from MPC20 30 
All other, net(3)(3)
Net cash used in financing activities(2,459)(2,867)
Net change in cash, cash equivalents and restricted cash722 108 
Cash, cash equivalents and restricted cash at beginning of period238 13 
Cash, cash equivalents and restricted cash at end of period$960 $121 

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

Consolidated Statements of Equity and Series A Preferred Units (Unaudited)

(In millions)Common
Series B Preferred Unit-holdersAccumulated Other Comprehensive LossNon-controlling
TotalSeries A Preferred Unit-holders
Balance at December 31, 2022$8,413 $3,293 $611 $(8)$237 $12,546 $968 
Net income323 592 5  9 929 23 
Redemption of Series B preferred units(2)(3)(595)  (600)— 
Distributions(275)(502)(21) (10)(808)(23)
Contributions 8    8 — 
Other   4 1 5 — 
Balance at March 31, 2023$8,459 $3,388 $ $(4)$237 $12,080 $968 
Net income322 588   9 919 23 
Distributions(274)(502)  (9)(785)(23)
Contributions 5    5 — 
Other1 1    2 — 
Balance at June 30, 2023$8,508 $3,480 $ $(4)$237 $12,221 $968 
Net income297 596   10 903 25 
Unit repurchases      — 
Distributions(274)(502)  (11)(787)(23)
Contributions 7    7 — 
Other2     2 — 
Balance at September 30, 2023$8,533 $3,581 $ $(4)$236 $12,346 $970 
Series B Preferred Unit-holdersAccumulated Other Comprehensive LossNon-controlling
TotalSeries A Preferred Unit-holders
Balance at December 31, 2021$8,579 $2,638 $611 $(17)$241 $12,052 $965 
Net income287 506 11  8 812 21 
Unit repurchases(100)    (100)— 
Distributions(260)(456)(21) (9)(746)(21)
Contributions 10    10 — 
Other(1)  9  8 — 
Balance at March 31, 2022$8,505 $2,698 $601 $(8)$240 $12,036 $965 
Net income304 540 10  9 863 21 
Unit repurchases(35)    (35)— 
Distributions(257)(457)  (10)(724)(21)
Contributions 2    2 — 
Other1 1    2 — 
Balance at June 30, 2022$8,518 $2,784 $611 $(8)$239 $12,144 $965 
Net income502 893 10  9 1,414 23 
Unit repurchases(196)    (196)— 
Distributions(258)(456)(20) (10)(744)(21)
Contributions 55    55 — 
Other3     3 — 
Balance at September 30, 2022$8,569 $3,276 $601 $(8)$238 $12,676 $967 

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

Notes to Consolidated Financial Statements (Unaudited)

1. Description of the Business and Basis of Presentation

Description of the Business

MPLX LP is a diversified, large-cap master limited partnership formed by Marathon Petroleum Corporation that owns and operates midstream energy infrastructure and logistics assets, and provides fuels distribution services. We are engaged in the gathering, transportation, storage and distribution of crude oil, refined products, other hydrocarbon-based products and renewables; the gathering, processing and transportation of natural gas; and the transportation, fractionation, storage and marketing of NGLs. MPLX’s principal executive office is located in Findlay, Ohio. MPLX was formed on March 27, 2012 as a Delaware limited partnership and completed its initial public offering on October 31, 2012.

MPLX’s business consists of two segments based on the nature of services it offers: Logistics and Storage (“L&S”), which relates primarily to crude oil, refined products, other hydrocarbon-based products and renewables; and Gathering and Processing (“G&P”), which relates primarily to natural gas and NGLs. See Note 7 for additional information regarding the operations and results of these segments.

Basis of Presentation

These interim consolidated financial statements are unaudited; however, in the opinion of MPLX’s management, these statements reflect all adjustments necessary for a fair statement of the results for the periods reported. All such adjustments are of a normal, recurring nature unless otherwise disclosed. These interim consolidated financial statements, including the notes, have been prepared in accordance with the rules and regulations of the SEC applicable to interim period financial statements and do not include all of the information and disclosures required by GAAP for complete financial statements. Certain information derived from our audited annual financial statements, prepared in accordance with GAAP, has been condensed or omitted from these interim financial statements.

These interim consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in our Annual Report on Form 10-K for the year ended December 31, 2022. The results of operations for the three and nine months ended September 30, 2023 are not necessarily indicative of the results to be expected for the full year.

MPLX’s consolidated financial statements include all majority-owned and controlled subsidiaries. For non-wholly owned consolidated subsidiaries, the interests owned by third parties have been recorded as Noncontrolling interests on the accompanying Consolidated Balance Sheets. Intercompany accounts and transactions have been eliminated. MPLX’s investments in which MPLX exercises significant influence but does not control and does not have a controlling financial interest are accounted for using the equity method. MPLX’s investments in VIEs in which MPLX exercises significant influence but does not control and is not the primary beneficiary are also accounted for using the equity method.

2. Accounting Standards

Not Yet Adopted
ASU 2023-01, Leases (Topic 842): Common Control Arrangements
In March 2023, the FASB issued an ASU to amend certain provisions of ASC 842 that apply to arrangements between related parties under common control. The ASU amends the accounting for the amortization period of leasehold improvements in common-control leases for all entities and requires certain disclosures when the lease term is shorter than the useful life of the asset. This ASU is effective for fiscal years beginning after December 15, 2023, including interim periods within those fiscal years. Early adoption is permitted. We do not expect the application of this ASU to have a material impact on our consolidated financial statements or financial disclosures.


3. Investments and Noncontrolling Interests

The following table presents MPLX’s equity method investments at the dates indicated:

Ownership as ofCarrying value at
September 30,September 30,December 31,
(In millions, except ownership percentages)VIE202320232022
Andeavor Logistics Rio Pipeline LLCX67%$174 $177 
Illinois Extension Pipeline Company, L.L.C.35%238 236 
LOOP LLC41%301 287 
MarEn Bakken Company LLC(1)
25%453 475 
Minnesota Pipe Line Company, LLC17%174 178 
Whistler Pipeline LLC38%212 211 
X298 269 
Total L&S1,850 1,833 
Centrahoma Processing LLC40%117 131 
MarkWest EMG Jefferson Dry Gas Gathering Company, L.L.CX67%339 335 
MarkWest Torñado GP, L.L.C.X60%310 306 
MarkWest Utica EMG, L.L.C.X58%684 669 
Rendezvous Gas Services, L.L.C.X78%130 137 
Sherwood Midstream Holdings LLCX51%116 125 
Sherwood Midstream LLCX50%507 512 
X46 47 
Total G&P2,249 2,262 
Total$4,099 $4,095 
(1)    The investment in MarEn Bakken Company LLC includes our 9.19 percent indirect interest in a joint venture (“Dakota Access”) that owns and operates the Dakota Access Pipeline and Energy Transfer Crude Oil Pipeline projects, collectively referred to as the Bakken Pipeline system or DAPL.    
(2)    Some investments included within Other have also been deemed to be VIEs.

For those entities that have been deemed to be VIEs, neither MPLX nor any of its subsidiaries have been deemed to be the primary beneficiary due to voting rights on significant matters. While we have the ability to exercise influence through participation in the management committees which make all significant decisions, we have equal influence over each committee as a joint interest partner and all significant decisions require the consent of the other investors without regard to economic interest. As such, we have determined that these entities should not be consolidated and applied the equity method of accounting with respect to our investments in each entity.

MPLX’s maximum exposure to loss as a result of its involvement with equity method investments includes its equity investment, any additional capital contribution commitments and any operating expenses incurred by the subsidiary operator in excess of its compensation received for the performance of the operating services. MPLX did not provide any financial support to equity method investments that it was not contractually obligated to provide during the nine months ended September 30, 2023. See Note 15 for information on our Guarantees related to indebtedness of equity method investees.

4. Related Party Agreements and Transactions

MPLX engages in transactions with both MPC and certain of its equity method investments as part of its normal business; however, transactions with MPC make up the majority of MPLX’s related party transactions. Transactions with related parties are further described below.

MPLX has various long-term, fee-based commercial agreements with MPC. Under these agreements, MPLX provides transportation, gathering, terminal, fuels distribution, marketing, storage, management, operational and other services to MPC. MPC has committed to provide MPLX with minimum quarterly throughput volumes on crude oil and refined products and other fees for storage capacity; operating and management fees; and reimbursements for certain direct and indirect costs. MPC has also committed to provide a fixed fee for 100 percent of available capacity for boats, barges and third-party chartered equipment under the marine transportation service agreement. MPLX also has a keep-whole commodity agreement with MPC under which MPC pays us a processing fee for NGLs related to keep-whole agreements and delivers shrink gas to the producers on our

behalf. We pay MPC a marketing fee in exchange for assuming the commodity risk. Additionally, MPLX has obligations to MPC for services provided to MPLX by MPC under omnibus and employee services-type agreements as well as other agreements.

During the second quarter of 2023, several terminal and storage services agreements with MPC were amended for certain items, including exercise of a five-year renewal option, with terms now extending to 2028.

Related Party Loan

MPLX is party to a loan agreement (the “MPC Loan Agreement”) with MPC. Under the terms of the MPC Loan Agreement, MPC extends loans to MPLX on a revolving basis as requested by MPLX and as agreed to by MPC. The borrowing capacity of the MPC Loan Agreement is $1.5 billion aggregate principal amount of all loans outstanding at any one time. The MPC Loan Agreement is scheduled to expire, and borrowings under the loan agreement are scheduled to mature and become due and payable, on July 31, 2024, provided that MPC may demand payment of all or any portion of the outstanding principal amount of the loan, together with all accrued and unpaid interest and other amounts (if any), at any time prior to maturity. Borrowings under the MPC Loan Agreement bear interest at one-month term SOFR adjusted upward by 0.10 percent plus 1.25 percent or such lower rate as would be applicable to such loans under the MPLX Credit Agreement as discussed in Note 11.

There was no activity on the MPC Loan Agreement for the nine months ended September 30, 2023.

Related Party Revenue

Related party sales to MPC primarily consist of crude oil and refined products pipeline based on tariff or contracted rates; storage, terminal and fuels distribution services based on contracted rates; and marine transportation services. Related party sales to MPC also consist of revenue related to volume deficiency credits.

MPLX also has operating agreements with MPC under which it receives a fee for operating MPC’s retained pipeline assets and a fixed annual fee for providing oversight and management services required to run the marine business. MPLX also receives management fee revenue for engineering, construction and administrative services for operating certain of its equity method investments. Amounts earned under these agreements are classified as Other income - related parties in the Consolidated Statements of Income.

Certain product sales to MPC and other related parties net to zero within the consolidated financial statements as the transactions are recorded net due to the terms of the agreements under which such product was sold. For the three and nine months ended September 30, 2023, these sales totaled $192 million and $540 million, respectively. For the three and nine months ended September 30, 2022, these sales totaled $235 million and $809 million, respectively.

Related Party Expenses

MPC charges MPLX for executive management services and certain general and administrative services provided to MPLX under the terms of our omnibus agreements (“Omnibus charges”) and for certain employee services provided to MPLX under employee services agreements (“ESA charges”). Omnibus charges and ESA charges are classified as Rental cost of sales - related parties, Purchases - related parties, or General and administrative expenses depending on the nature of the asset or activity with which the costs are associated. In addition to these agreements, MPLX purchases products from MPC, makes payments to MPC in its capacity as general contractor to MPLX, and has certain rent and lease agreements with MPC.

For the three and nine months ended September 30, 2023, General and administrative expenses incurred from MPC totaled $72 million and $197 million, respectively. For the three and nine months ended September 30, 2022, General and administrative expenses incurred from MPC totaled $60 million and $173 million, respectively.

Some charges incurred under the omnibus and employee service agreements are related to engineering services and are associated with assets under construction. These charges are added to Property, plant and equipment, net on the Consolidated Balance Sheets. For the three and nine months ended September 30, 2023, these charges totaled $28 million and $56 million, respectively. For the three and nine months ended September 30, 2022, these charges totaled $16 million and $54 million, respectively.

Related Party Assets and Liabilities

Assets and liabilities with related parties appearing in the Consolidated Balance Sheets are detailed in the table below. This table identifies the various components of related party assets and liabilities, including those associated with leases and deferred revenue on minimum volume commitments. If MPC fails to meet its minimum committed volumes, MPC will pay MPLX a deficiency payment based on the terms of the agreement. The deficiency amounts received under these agreements (excluding payments received under agreements classified as sales-type leases) are recorded as Current liabilities - related parties. In many cases, MPC may then apply the amount of any such deficiency payments as a credit for volumes in excess of its minimum volume commitment in future periods under the terms of the applicable agreements. MPLX recognizes related party revenues for the deficiency payments when credits are used for volumes in excess of minimum quarterly volume commitments, where it is

probable the customer will not use the credit in future periods or upon the expiration of the credits. The use or expiration of the credits is a decrease in Current liabilities - related parties. Deficiency payments under agreements that have been classified as sales-type leases are recorded as a reduction against the corresponding lease receivable. In addition, capital projects MPLX undertakes at the request of MPC are reimbursed in cash and recognized as revenue over the remaining term of the applicable agreements or in some cases, as a contribution from MPC.

(In millions)September 30,
December 31,
Current assets - related parties
Receivables$599 $610 
Lease receivables140 111 
Prepaid14 5 
Other6 3 
Total759 729 
Noncurrent assets - related parties
Long-term lease receivables811 883 
Right of use assets227 228 
Unguaranteed residual asset115 87 
Long-term receivables21 27 
Total1,174 1,225 
Current liabilities - related parties
MPC loan agreement and other payables(1)
312 262 
Deferred revenue74 80 
Operating lease liabilities1 1 
Total387 343 
Long-term liabilities - related parties
Long-term operating lease liabilities226 228 
Long-term deferred revenue117 110 
Total$343 $338 
(1)    There were no borrowings outstanding on the MPC Loan Agreement as of September 30, 2023 or December 31, 2022.

Other Related Party Transactions

From time to time, MPLX may also sell to or purchase from related parties, assets and inventory at the lesser of average unit cost or net realizable value.
5. Equity

The changes in the number of common units during the nine months ended September 30, 2023 are summarized below:
(In units)Common Units
Balance at December 31, 20221,001,020,616 
Unit-based compensation awards196,428 
Balance at September 30, 20231,001,217,044 

Unit Repurchase Program

On August 2, 2022, we announced the board authorization for the repurchase of up to $1 billion of MPLX common units held by the public. This unit repurchase authorization has no expiration date. We may utilize various methods to effect the repurchases, which could include open market repurchases, negotiated block transactions, accelerated unit repurchases, tender offers or open market solicitations for units, some of which may be effected through Rule 10b5-1 plans. The timing and amount of future repurchases, if any, will depend upon several factors, including market and business conditions, and such repurchases may be discontinued at any time.

No units were repurchased during the three or nine months ended September 30, 2023. As of September 30, 2023, we had $846 million remaining under the unit repurchase authorization.


Redemption of the Series B Preferred Units

On February 15, 2023, MPLX exercised its right to redeem all 600,000 outstanding 6.875 percent Fixed-to-Floating Rate Cumulative Redeemable Perpetual Preferred Units (the “Series B preferred units”). MPLX paid unitholders the Series B preferred unit redemption price of $1,000 per unit.

Distributions on the Series B preferred units were payable semi-annually in arrears on the 15th day, or the first business day thereafter, of February and August of each year up to and including February 15, 2023. In accordance with these terms, MPLX made a final cash distribution of $21 million to Series B preferred unitholders on February 15, 2023, in conjunction with the redemption.

The changes in the Series B preferred unit balance during the nine months ended September 30, 2023 and September 30, 2022 are included in the Consolidated Statements of Equity within Series B preferred units.


On October 24, 2023, MPLX declared a cash distribution for the third quarter of 2023, totaling $851 million, or $0.850 per common unit. This distribution will be paid on November 13, 2023 to common unitholders of record on November 3, 2023. This rate will also be received by Series A preferred unitholders.

Quarterly distributions for 2023 and 2022 are summarized below:
(Per common unit)20232022
March 31,$0.775 $0.705 
June 30,0.775 0.705 
September 30,$0.850 $0.775 

The allocation of total quarterly cash distributions to limited and preferred unitholders is as follows for the three and nine months ended September 30, 2023 and September 30, 2022. Distributions, although earned, are not accrued until declared. MPLX’s distributions are declared subsequent to quarter end; therefore, the following table represents total cash distributions applicable to the period in which the distributions were earned.
Three Months Ended 
September 30,
Nine Months Ended 
September 30,
(In millions)2023202220232022
Common and preferred unit distributions:
Common unitholders, includes common units of general partner$851 $777 $2,403 $2,204 
Series A preferred unit distributions25 23 71 65 
Series B preferred unit distributions(1)
 10 5 31 
Total cash distributions declared$876 $810 $2,479 $2,300 
(1)    The nine months ended September 30, 2023 includes the portion of the $21 million distribution paid to the Series B preferred unitholders on February 15, 2023 that was earned during the period prior to redemption.

6. Net Income Per Limited Partner Unit

Net income per unit applicable to common units is computed by dividing net income attributable to MPLX LP less income allocated to participating securities by the weighted average number of common units outstanding.

During the three and nine months ended September 30, 2023 and September 30, 2022, MPLX had participating securities consisting of common units, certain equity-based compensation awards, Series A preferred units, and Series B preferred units and also had dilutive potential common units consisting of certain equity-based compensation awards. Potential common units omitted from the diluted earnings per unit calculation for the three and nine months ended September 30, 2023 and September 30, 2022 were less than 1 million.

Three Months Ended 
September 30,
Nine Months Ended 
September 30,
(In millions)2023202220232022
Net income attributable to MPLX LP$918 $1,428 $2,794 $3,128 
Less: Distributions declared on Series A preferred units25 23 71 65 
Distributions declared on Series B preferred units 10 5 31 
Limited partners’ distributions declared on MPLX common units (including common units of general partner)851 777 2,403 2,204 
Undistributed net gain attributable to MPLX LP$42 $618 $315 $828 

Three Months Ended September 30, 2023
(In millions, except per unit data)Limited Partners’
Common Units
Series A Preferred UnitsTotal
Basic and diluted net income attributable to MPLX LP per unit
Net income attributable to MPLX LP:
Distributions declared$851 $25 $876 
Undistributed net gain attributable to MPLX LP41 1 42 
Net income attributable to MPLX LP(1)
$892 $26 $918 
Weighted average units outstanding:
Net income attributable to MPLX LP per limited partner unit:
(1)    Allocation of net income attributable to MPLX LP assumes all earnings for the period had been distributed based on the distribution priorities applicable to the period.

Three Months Ended September 30, 2022
(In millions, except per unit data)Limited Partners’
Common Units
Series A Preferred UnitsSeries B Preferred UnitsTotal
Basic and diluted net income attributable to MPLX LP per unit
Net income attributable to MPLX LP:
Distributions declared$777 $23 $10 $810 
Undistributed net gain attributable to MPLX LP(1)
600 18  618 
Net income attributable to MPLX LP(2)
$1,377 $41 $10 $1,428 
Weighted average units outstanding:
Net income attributable to MPLX LP per limited partner unit:
(1)    The undistributed net gain attributable to MPLX LP includes a $509 million non-cash gain on a lease reclassification for the three months ended September 30, 2022. See Note 14 for additional information.
(2)    Allocation of net income attributable to MPLX LP assumes all earnings for the period had been distributed based on the distribution priorities applicable to the period.


Nine Months Ended September 30, 2023
(In millions, except per unit data)Limited Partners’
Common Units
Series A Preferred UnitsSeries B Preferred UnitsTotal
Basic and diluted net income attributable to MPLX LP per unit
Net income attributable to MPLX LP:
Distributions declared$2,403 $71 $5 $2,479 
Undistributed net gain attributable to MPLX LP306 9  315 
Net income attributable to MPLX LP(1)
2,709 $80 $5 2,794 
Impact of redemption of Series B preferred units(5)(5)
Income available to common unitholders$2,704 $2,789 
Weighted average units outstanding:
Net income attributable to MPLX LP per limited partner unit:
(1)    Allocation of net income attributable to MPLX LP assumes all earnings for the period had been distributed based on the distribution priorities applicable to the period.

Nine Months Ended September 30, 2022
(In millions, except per unit data)Limited Partners’
Common Units
Series A Preferred UnitsSeries B Preferred UnitsTotal
Basic and diluted net income attributable to MPLX LP per unit
Net income attributable to MPLX LP:
Distributions declared$2,204 $65 $31 $2,300 
Undistributed net gain attributable to MPLX LP(1)
804 24  828 
Net income attributable to MPLX LP(2)
$3,008 $89 $31 $3,128 
Weighted average units outstanding:
Net income attributable to MPLX LP per limited partner unit:
(1)    The undistributed net gain attributable to MPLX LP includes a $509 million non-cash gain on a lease reclassification for the nine months ended September 30, 2022. See Note 14 for additional information.
(2)    Allocation of net income attributable to MPLX LP assumes all earnings for the period had been distributed based on the distribution priorities applicable to the period.

7. Segment Information

MPLX’s chief operating decision maker (“CODM”) is the chief executive officer of its general partner. The CODM reviews MPLX’s discrete financial information, makes operating decisions, assesses financial performance and allocates resources on a type of service basis. MPLX has two reportable segments: L&S and G&P. Each of these segments is organized and managed based upon the nature of the products and services it offers.

L&S – gathers, transports, stores and distributes crude oil, refined products, other hydrocarbon-based products and renewables. Also includes the operation of refining logistics, fuels distribution and inland marine businesses, terminals, rail facilities, and storage caverns.
G&P – gathers, processes and transports natural gas; and transports, fractionates, stores and markets NGLs.

Our CODM evaluates the performance of our segments using Segment Adjusted EBITDA. Amounts included in net income and excluded from Segment Adjusted EBITDA include: (i) depreciation and amortization; (ii) interest and other financial costs; (iii) income/(loss) from equity method investments; (iv) distributions and adjustments related to equity method investments; (v) gain on sales-type leases; (vi) impairment expense; (vii) noncontrolling interests; and (viii) other adjustments, as applicable. These items are either: (i) believed to be non-recurring in nature; (ii) not believed to be allocable or controlled by the segment; or (iii) are

not tied to the operational performance of the segment. Assets by segment are not a measure used to assess the performance of the Partnership by our CODM and thus are not reported in our disclosures.

The tables below present information about revenues and other income, Segment Adjusted EBITDA, capital expenditures and investments in unconsolidated affiliates for our reportable segments:
Three Months Ended 
September 30,
Nine Months Ended 
September 30,
(In millions)2023202220232022
Service revenue$1,130 $1,038 $3,223 $3,031 
Rental income216 210 638 593 
Product related revenue6 4 14 15 
Sales-type lease revenue129 118 379 343 
Income from equity method investments95 72 248 183 
Other income15 8 47 42 
Total segment revenues and other income(1)
1,591 1,450 4,549 4,207 
Segment Adjusted EBITDA(2)
1,091 969 3,139 2,839 
Capital expenditures73 80 251 238 
Investments in unconsolidated affiliates7 12 23 90 
Service revenue549 537 1,620 1,528 
Rental income52 66 155 239 
Product related revenue598 742 1,629 2,263 
Sales-type lease revenue 34 28 101 28 
Income from equity method investments64 53 190 152 
Other income(3)
24 525 71 534 
Total segment revenues and other income(1)
1,321 1,951 3,766 4,744 
Segment Adjusted EBITDA(2)
505 502 1,507 1,482 
Capital expenditures151 146 417 336 
Investments in unconsolidated affiliates$6 $30 $67 $108 
(1)    Within the total segment revenues and other income amounts presented above, third party revenues for the L&S segment were $207 million and $564 million for the three and nine months ended September 30, 2023, respectively, and $175 million and $468 million for the three and nine months ended September 30, 2022, respectively. Third party revenues for the G&P segment were $1,248 million and $3,553 million for the three and nine months ended September 30, 2023, respectively, and $1,885 million and $4,551 million for the three and nine months ended September 30, 2022, respectively.
(2)    See below for the reconciliation from Segment Adjusted EBITDA to Net income.
(3)    The three and nine months ended September 30, 2022 include a $509 million non-cash gain on a lease reclassification. See Note 14 in the unaudited consolidated financial statements for additional information.


The table below provides a reconciliation of Segment Adjusted EBITDA for reportable segments to Net income.
Three Months Ended 
September 30,
Nine Months Ended 
September 30,
(In millions)2023202220232022
Reconciliation to Net income:
L&S Segment Adjusted EBITDA$1,091 $969 $3,139 $2,839 
G&P Segment Adjusted EBITDA505 502 1,507 1,482 
Total reportable segments1,596 1,471 4,646 4,321 
Depreciation and amortization(1)
Gain on sales-type leases 509  509 
Interest and other financial costs(225)(236)(701)(691)
Income from equity method investments159 125 438 335 
Distributions/adjustments related to equity method investments(208)(166)(551)(450)
Adjusted EBITDA attributable to noncontrolling interests11 10 31 29 
Garyville incident response costs(2)
(63) (63) 
(41)26 (71)26 
Net income$928 $1,437 $2,822 $3,154 
(1)    Depreciation and amortization attributable to L&S was $130 million and $399 million for the three and nine months ended September 30, 2023, respectively, and $128 million and $387 million for the three and nine months ended September 30, 2022, respectively. Depreciation and amortization attributable to G&P was $171 million and $508 million for the three and nine months ended September 30, 2023, respectively, and $174 million and $538 million for the three and nine months ended September 30, 2022, respectively.
(2)    In August 2023, a naphtha release and resulting fire occurred at our Garyville Tank Farm resulting in the loss of four storage tanks with a combined shell capacity of 894 thousand barrels. We incurred $63 million of incident response costs during the three and nine months ended September 30, 2023.
(3)    Includes unrealized derivative gain/(loss), non-cash equity-based compensation, provision for income taxes, and other miscellaneous items.

8. Property, Plant and Equipment
Property, plant and equipment with associated accumulated depreciation is shown below:

September 30, 2023December 31, 2022
(In millions)Gross PP&EAccumulated DepreciationNet PP&EGross PP&EAccumulated DepreciationNet PP&E
L&S $12,633 $3,919 $8,714 $12,416 $3,554 $8,862 
G&P 13,844 3,938 9,906 13,495 3,509 9,986 
Total$26,477 $7,857 $18,620 $25,911 $7,063 $18,848 

We capitalize interest as part of the cost of major projects during the construction period. Capitalized interest totaled $4 million and $11 million for the three and nine months ended September 30, 2023, respectively, and $2 million and $7 million for the three and nine months ended September 30, 2022, respectively.

9. Fair Value Measurements

Fair Values – Recurring

The following table presents the impact on the Consolidated Balance Sheets of MPLX’s financial instruments carried at fair value on a recurring basis as of September 30, 2023 and December 31, 2022 by fair value hierarchy level.