2024Q30001552000--12-31falseP5YP5Yhttp://fasb.org/us-gaap/2024#ProfitLosshttp://fasb.org/us-gaap/2024#ProfitLosshttp://fasb.org/us-gaap/2024#ProfitLosshttp://fasb.org/us-gaap/2024#ProfitLoss3111115http://fasb.org/us-gaap/2024#OtherLiabilitiesCurrent http://fasb.org/us-gaap/2024#OtherLiabilitiesNoncurrenthttp://fasb.org/us-gaap/2024#OtherLiabilitiesCurrent http://fasb.org/us-gaap/2024#OtherLiabilitiesNoncurrentxbrli:sharesiso4217:USDiso4217:USDxbrli:sharesxbrli:pureiso4217:USDutr:galutr:gal00015520002024-01-012024-09-3000015520002024-10-310001552000us-gaap:ServiceMember2024-07-012024-09-300001552000us-gaap:ServiceMember2023-07-012023-09-300001552000us-gaap:ServiceMember2024-01-012024-09-300001552000us-gaap:ServiceMember2023-01-012023-09-300001552000us-gaap:ServiceOtherMember2024-07-012024-09-300001552000us-gaap:ServiceOtherMember2023-07-012023-09-300001552000us-gaap:ServiceOtherMember2024-01-012024-09-300001552000us-gaap:ServiceOtherMember2023-01-012023-09-300001552000us-gaap:NonrelatedPartyMember2024-07-012024-09-300001552000us-gaap:NonrelatedPartyMember2023-07-012023-09-300001552000us-gaap:NonrelatedPartyMember2024-01-012024-09-300001552000us-gaap:NonrelatedPartyMember2023-01-012023-09-300001552000us-gaap:RelatedPartyMember2024-07-012024-09-300001552000us-gaap:RelatedPartyMember2023-07-012023-09-300001552000us-gaap:RelatedPartyMember2024-01-012024-09-300001552000us-gaap:RelatedPartyMember2023-01-012023-09-300001552000us-gaap:ProductMember2024-07-012024-09-300001552000us-gaap:ProductMember2023-07-012023-09-300001552000us-gaap:ProductMember2024-01-012024-09-300001552000us-gaap:ProductMember2023-01-012023-09-3000015520002024-07-012024-09-3000015520002023-07-012023-09-3000015520002023-01-012023-09-300001552000us-gaap:OilAndGasServiceMember2024-07-012024-09-300001552000us-gaap:OilAndGasServiceMember2023-07-012023-09-300001552000us-gaap:OilAndGasServiceMember2024-01-012024-09-300001552000us-gaap:OilAndGasServiceMember2023-01-012023-09-300001552000us-gaap:NaturalGasMidstreamMember2024-07-012024-09-300001552000us-gaap:NaturalGasMidstreamMember2023-07-012023-09-300001552000us-gaap:NaturalGasMidstreamMember2024-01-012024-09-300001552000us-gaap:NaturalGasMidstreamMember2023-01-012023-09-300001552000us-gaap:SeriesAPreferredStockMember2024-07-012024-09-300001552000us-gaap:SeriesAPreferredStockMember2023-07-012023-09-300001552000us-gaap:SeriesAPreferredStockMember2024-01-012024-09-300001552000us-gaap:SeriesAPreferredStockMember2023-01-012023-09-300001552000us-gaap:SeriesBPreferredStockMember2024-07-012024-09-300001552000us-gaap:SeriesBPreferredStockMember2023-07-012023-09-300001552000us-gaap:SeriesBPreferredStockMember2024-01-012024-09-300001552000us-gaap:SeriesBPreferredStockMember2023-01-012023-09-3000015520002024-09-3000015520002023-12-310001552000us-gaap:RelatedPartyMember2024-09-300001552000us-gaap:RelatedPartyMember2023-12-310001552000us-gaap:NonrelatedPartyMember2024-09-300001552000us-gaap:NonrelatedPartyMember2023-12-310001552000us-gaap:SeriesAPreferredStockMember2024-09-300001552000us-gaap:SeriesAPreferredStockMember2023-12-310001552000us-gaap:CommonStockMemberus-gaap:NonrelatedPartyMember2024-09-300001552000us-gaap:CommonStockMemberus-gaap:NonrelatedPartyMember2023-12-310001552000us-gaap:CommonStockMemberus-gaap:RelatedPartyMember2024-09-300001552000us-gaap:CommonStockMemberus-gaap:RelatedPartyMember2023-12-3100015520002022-12-3100015520002023-09-300001552000us-gaap:CommonStockMember2023-12-310001552000mplx:CommonStock_RelatedPartyInterestMember2023-12-310001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2023-12-310001552000us-gaap:NoncontrollingInterestMember2023-12-310001552000mplx:TemporaryEquityMember2023-12-310001552000us-gaap:CommonStockMember2024-01-012024-03-310001552000mplx:CommonStock_RelatedPartyInterestMember2024-01-012024-03-310001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2024-01-012024-03-310001552000us-gaap:NoncontrollingInterestMember2024-01-012024-03-3100015520002024-01-012024-03-310001552000mplx:TemporaryEquityMember2024-01-012024-03-310001552000us-gaap:CommonStockMember2024-03-310001552000mplx:CommonStock_RelatedPartyInterestMember2024-03-310001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2024-03-310001552000us-gaap:NoncontrollingInterestMember2024-03-3100015520002024-03-310001552000mplx:TemporaryEquityMember2024-03-310001552000us-gaap:CommonStockMember2024-04-012024-06-300001552000mplx:CommonStock_RelatedPartyInterestMember2024-04-012024-06-300001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2024-04-012024-06-300001552000us-gaap:NoncontrollingInterestMember2024-04-012024-06-3000015520002024-04-012024-06-300001552000mplx:TemporaryEquityMember2024-04-012024-06-300001552000us-gaap:CommonStockMember2024-06-300001552000mplx:CommonStock_RelatedPartyInterestMember2024-06-300001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2024-06-300001552000us-gaap:NoncontrollingInterestMember2024-06-3000015520002024-06-300001552000mplx:TemporaryEquityMember2024-06-300001552000us-gaap:CommonStockMember2024-07-012024-09-300001552000mplx:CommonStock_RelatedPartyInterestMember2024-07-012024-09-300001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2024-07-012024-09-300001552000us-gaap:NoncontrollingInterestMember2024-07-012024-09-300001552000mplx:TemporaryEquityMember2024-07-012024-09-300001552000us-gaap:CommonStockMember2024-09-300001552000mplx:CommonStock_RelatedPartyInterestMember2024-09-300001552000us-gaap:AccumulatedOtherComprehensiveIncomeMember2024-09-300001552000us-gaap:NoncontrollingInterestMember2024-09-300001552000mplx:TemporaryEquityMember2024-09-300001552000us-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:TemporaryEquityMember2023-09-300001552000mplx:BANGLLLCMember2024-07-310001552000mplx:BANGLLLCMember2024-07-312024-07-310001552000mplx:WPCParentLLCMembermplx:EnbridgeInc.Member2024-05-290001552000mplx:WhistlerPipelineLLCMembermplx:MPLXLPMember2024-05-280001552000mplx:WPCParentLLCMembermplx:MPLXLPMember2024-05-290001552000mplx:WPCParentLLCMember2024-05-292024-05-290001552000mplx:UticaMidstreamMember2024-03-222024-03-220001552000mplx:OhioGatheringCompanyL.L.C.Member2024-03-220001552000mplx:OhioCondensateCompanyL.L.C.Member2024-03-220001552000mplx:UticaMidstreamMember2024-03-220001552000mplx:OhioCondensateCompanyL.L.C.Member2024-03-222024-03-220001552000mplx:BANGLLLCMembermplx:LogisticsandStorageMember2024-09-300001552000mplx:BANGLLLCMembermplx:LogisticsandStorageMember2023-12-310001552000mplx:IllinoisExtensionPipelineCompanyLLCMembermplx:LogisticsandStorageMember2024-09-300001552000mplx:IllinoisExtensionPipelineCompanyLLCMembermplx:LogisticsandStorageMember2023-12-310001552000mplx:LoopLLCMembermplx:LogisticsandStorageMember2024-09-300001552000mplx:LoopLLCMembermplx:LogisticsandStorageMember2023-12-310001552000mplx:MarEnBakkenCompanyLLCMembermplx:LogisticsandStorageMember2024-09-300001552000mplx:MarEnBakkenCompanyLLCMembermplx:LogisticsandStorageMember2023-12-310001552000mplx:WPCParentLLCMembermplx:LogisticsandStorageMember2024-09-300001552000mplx:WhistlerPipelineLLCMembermplx:LogisticsandStorageMember2023-12-310001552000mplx:OtherVIEsandNonVIEsMembermplx:LogisticsandStorageMember2024-09-300001552000mplx:OtherVIEsandNonVIEsMembermplx:LogisticsandStorageMember2023-12-310001552000mplx:LogisticsandStorageMember2024-09-300001552000mplx:LogisticsandStorageMember2023-12-310001552000mplx:MarkWestEMGJeffersonDryGasGatheringCompanyL.L.C.Membermplx:GatheringandProcessingMember2024-09-300001552000mplx:MarkWestEMGJeffersonDryGasGatheringCompanyL.L.C.Membermplx:GatheringandProcessingMember2023-12-310001552000mplx:MarkWestUticaEMGMembermplx:GatheringandProcessingMember2024-09-300001552000mplx:MarkWestUticaEMGMembermplx:GatheringandProcessingMember2023-12-310001552000mplx:OhioGatheringCompanyL.L.C.Membermplx:GatheringandProcessingMember2024-09-300001552000mplx:OhioGatheringCompanyL.L.C.Membermplx:GatheringandProcessingMember2023-12-310001552000mplx:SherwoodMidstreamLLCMembermplx:GatheringandProcessingMember2024-09-300001552000mplx:SherwoodMidstreamLLCMembermplx:GatheringandProcessingMember2023-12-310001552000mplx:OtherVIEsandNonVIEsMembermplx:GatheringandProcessingMember2024-09-300001552000mplx:OtherVIEsandNonVIEsMembermplx:GatheringandProcessingMember2023-12-310001552000mplx:GatheringandProcessingMember2024-09-300001552000mplx:GatheringandProcessingMember2023-12-310001552000mplx:IndirectOwnershipInterestMembermplx:BakkenPipelineSystemMembermplx:LogisticsandStorageMember2024-09-300001552000mplx:OhioGatheringCompanyL.L.C.Membermplx:GatheringandProcessingMember2024-03-220001552000mplx:IndirectOwnershipInterestMembermplx:OhioGatheringCompanyL.L.C.Membermplx:GatheringandProcessingMember2024-09-300001552000us-gaap:RelatedPartyMember2024-06-300001552000us-gaap:RevolvingCreditFacilityMemberus-gaap:RelatedPartyMember2024-09-300001552000us-gaap:RevolvingCreditFacilityMemberus-gaap:RelatedPartyMember2024-01-012024-09-300001552000us-gaap:RelatedPartyMemberus-gaap:AssetUnderConstructionMember2024-07-012024-09-300001552000us-gaap:RelatedPartyMemberus-gaap:AssetUnderConstructionMember2024-01-012024-09-300001552000us-gaap:RelatedPartyMemberus-gaap:AssetUnderConstructionMember2023-07-012023-09-300001552000us-gaap:RelatedPartyMemberus-gaap:AssetUnderConstructionMember2023-01-012023-09-300001552000us-gaap:RevolvingCreditFacilityMemberus-gaap:RelatedPartyMember2023-12-3100015520002022-08-020001552000us-gaap:SeriesAPreferredStockMember2024-09-300001552000us-gaap:SeriesBPreferredStockMember2023-02-152023-02-150001552000us-gaap:SeriesBPreferredStockMember2023-02-150001552000us-gaap:SubsequentEventMember2024-10-292024-10-290001552000us-gaap:CommonStockMemberus-gaap:SubsequentEventMember2024-11-152024-11-150001552000us-gaap:CommonStockMemberus-gaap:SubsequentEventMember2024-11-082024-11-080001552000us-gaap:CommonStockMember2024-07-012024-09-300001552000us-gaap:CommonStockMember2023-07-012023-09-300001552000us-gaap:CommonStockMember2024-01-012024-09-300001552000us-gaap:CommonStockMember2023-01-012023-09-300001552000us-gaap:OperatingSegmentsMemberus-gaap:ServiceMembermplx:LogisticsandStorageMember2024-07-012024-09-300001552000us-gaap:OperatingSegmentsMemberus-gaap:ServiceMembermplx:LogisticsandStorageMember2023-07-012023-09-300001552000us-gaap:OperatingSegmentsMemberus-gaap:ServiceMembermplx:LogisticsandStorageMember2024-01-012024-09-300001552000us-gaap:OperatingSegmentsMemberus-gaap:ServiceMembermplx:LogisticsandStorageMember2023-01-012023-09-300001552000us-gaap:OperatingSegmentsMembermplx:LogisticsandStorageMember2024-07-012024-09-300001552000us-gaap:OperatingSegmentsMembermplx:LogisticsandStorageMember2023-07-012023-09-300001552000us-gaap:OperatingSegmentsMembermplx:LogisticsandStorageMember2024-01-012024-09-300001552000us-gaap:OperatingSegmentsMembermplx:LogisticsandStorageMember2023-01-012023-09-300001552000us-gaap:OperatingSegmentsMemberus-gaap:ProductMembermplx:LogisticsandStorageMember2024-07-012024-09-300001552000us-gaap:OperatingSegmentsMemberus-gaap:ProductMembermplx:LogisticsandStorageMember2023-07-012023-09-300001552000us-gaap:OperatingSegmentsMemberus-gaap:ProductMembermplx:LogisticsandStorageMember2024-01-012024-09-300001552000us-gaap:OperatingSegmentsMemberus-gaap:ProductMembermplx:LogisticsandStorageMember2023-01-012023-09-300001552000us-gaap:OperatingSegmentsMemberus-gaap:ServiceMembermplx:GatheringandProcessingMember2024-07-012024-09-300001552000us-gaap:OperatingSegmentsMemberus-gaap:ServiceMembermplx:GatheringandProcessingMember2023-07-012023-09-300001552000us-gaap:OperatingSegmentsMemberus-gaap:ServiceMembermplx:GatheringandProcessingMember2024-01-012024-09-300001552000us-gaap:OperatingSegmentsMemberus-gaap:ServiceMembermplx:GatheringandProcessingMember2023-01-012023-09-300001552000us-gaap:OperatingSegmentsMembermplx:GatheringandProcessingMember2024-07-012024-09-300001552000us-gaap:OperatingSegmentsMembermplx:GatheringandProcessingMember2023-07-012023-09-300001552000us-gaap:OperatingSegmentsMembermplx:GatheringandProcessingMember2024-01-012024-09-300001552000us-gaap:OperatingSegmentsMembermplx:GatheringandProcessingMember2023-01-012023-09-300001552000us-gaap:OperatingSegmentsMemberus-gaap:ProductMembermplx:GatheringandProcessingMember2024-07-012024-09-300001552000us-gaap:OperatingSegmentsMemberus-gaap:ProductMembermplx:GatheringandProcessingMember2023-07-012023-09-300001552000us-gaap:OperatingSegmentsMemberus-gaap:ProductMembermplx:GatheringandProcessingMember2024-01-012024-09-300001552000us-gaap:OperatingSegmentsMemberus-gaap:ProductMembermplx:GatheringandProcessingMember2023-01-012023-09-300001552000us-gaap:NonrelatedPartyMembermplx:LogisticsandStorageMember2024-07-012024-09-300001552000us-gaap:NonrelatedPartyMembermplx:LogisticsandStorageMember2024-01-012024-09-300001552000us-gaap:NonrelatedPartyMembermplx:LogisticsandStorageMember2023-07-012023-09-300001552000us-gaap:NonrelatedPartyMembermplx:LogisticsandStorageMember2023-01-012023-09-300001552000us-gaap:NonrelatedPartyMembermplx:GatheringandProcessingMember2024-07-012024-09-300001552000us-gaap:NonrelatedPartyMembermplx:GatheringandProcessingMember2024-01-012024-09-300001552000us-gaap:NonrelatedPartyMembermplx:GatheringandProcessingMember2023-07-012023-09-300001552000us-gaap:NonrelatedPartyMembermplx:GatheringandProcessingMember2023-01-012023-09-3000015520002024-03-290001552000us-gaap:OperatingSegmentsMember2024-07-012024-09-300001552000us-gaap:OperatingSegmentsMember2023-07-012023-09-300001552000us-gaap:OperatingSegmentsMember2024-01-012024-09-300001552000us-gaap:OperatingSegmentsMember2023-01-012023-09-300001552000us-gaap:MaterialReconcilingItemsMember2024-07-012024-09-300001552000us-gaap:MaterialReconcilingItemsMember2023-07-012023-09-300001552000us-gaap:MaterialReconcilingItemsMember2024-01-012024-09-300001552000us-gaap:MaterialReconcilingItemsMember2023-01-012023-09-300001552000mplx:LogisticsandStorageMember2024-07-012024-09-300001552000mplx:LogisticsandStorageMember2024-01-012024-09-300001552000mplx:LogisticsandStorageMember2023-07-012023-09-300001552000mplx:LogisticsandStorageMember2023-01-012023-09-300001552000mplx:GatheringandProcessingMember2024-07-012024-09-300001552000mplx:GatheringandProcessingMember2024-01-012024-09-300001552000mplx:GatheringandProcessingMember2023-07-012023-09-300001552000mplx:GatheringandProcessingMember2023-01-012023-09-300001552000us-gaap:FairValueInputsLevel2Memberus-gaap:CommodityContractMemberus-gaap:OtherCurrentAssetsMember2024-09-300001552000us-gaap:FairValueInputsLevel2Memberus-gaap:CommodityContractMemberus-gaap:OtherCurrentLiabilitiesMember2024-09-300001552000us-gaap:FairValueInputsLevel2Memberus-gaap:CommodityContractMemberus-gaap:OtherCurrentAssetsMember2023-12-310001552000us-gaap:FairValueInputsLevel2Memberus-gaap:CommodityContractMemberus-gaap:OtherCurrentLiabilitiesMember2023-12-310001552000us-gaap:FairValueInputsLevel3Memberus-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:OtherCurrentAssetsMember2024-09-300001552000us-gaap:FairValueInputsLevel3Memberus-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:OtherCurrentLiabilitiesMember2024-09-300001552000us-gaap:FairValueInputsLevel3Memberus-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:OtherCurrentAssetsMember2023-12-310001552000us-gaap:FairValueInputsLevel3Memberus-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:OtherCurrentLiabilitiesMember2023-12-310001552000us-gaap:FairValueInputsLevel3Memberus-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:OtherNoncurrentAssetsMember2024-09-300001552000us-gaap:FairValueInputsLevel3Memberus-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:OtherNoncurrentLiabilitiesMember2024-09-300001552000us-gaap:FairValueInputsLevel3Memberus-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:OtherNoncurrentAssetsMember2023-12-310001552000us-gaap:FairValueInputsLevel3Memberus-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:OtherNoncurrentLiabilitiesMember2023-12-310001552000us-gaap:FairValueInputsLevel3Memberus-gaap:EmbeddedDerivativeFinancialInstrumentsMembersrt:MinimumMember2024-09-300001552000us-gaap:FairValueInputsLevel3Memberus-gaap:EmbeddedDerivativeFinancialInstrumentsMembersrt:MaximumMember2024-09-300001552000us-gaap:FairValueInputsLevel3Memberus-gaap:EmbeddedDerivativeFinancialInstrumentsMember2024-09-300001552000us-gaap:FairValueInputsLevel3Memberus-gaap:EmbeddedDerivativeFinancialInstrumentsMember2024-01-012024-09-300001552000mplx:NaturalGasMemberus-gaap:EmbeddedDerivativeFinancialInstrumentsMember2024-01-012024-09-300001552000us-gaap:EstimateOfFairValueFairValueDisclosureMember2024-09-300001552000us-gaap:CarryingReportedAmountFairValueDisclosureMember2024-09-300001552000us-gaap:EstimateOfFairValueFairValueDisclosureMember2023-12-310001552000us-gaap:CarryingReportedAmountFairValueDisclosureMember2023-12-310001552000us-gaap:PublicUtilitiesInventoryPropaneMemberus-gaap:ShortMemberus-gaap:OverTheCounterMember2024-09-300001552000mplx:NaturalGasMemberus-gaap:EmbeddedDerivativeFinancialInstrumentsMember2024-09-300001552000us-gaap:FairValueInputsLevel3Memberus-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:FairValueMeasurementsRecurringMember2024-09-300001552000us-gaap:FairValueInputsLevel3Memberus-gaap:EmbeddedDerivativeFinancialInstrumentsMemberus-gaap:FairValueMeasurementsRecurringMember2023-12-310001552000mplx:ProductSalesMember2024-07-012024-09-300001552000mplx:ProductSalesMember2023-07-012023-09-300001552000mplx:ProductSalesMember2024-01-012024-09-300001552000mplx:ProductSalesMember2023-01-012023-09-300001552000mplx:PurchasedproductcostsMember2024-07-012024-09-300001552000mplx:PurchasedproductcostsMember2023-07-012023-09-300001552000mplx:PurchasedproductcostsMember2024-01-012024-09-300001552000mplx:PurchasedproductcostsMember2023-01-012023-09-300001552000mplx:MPLXLPMember2024-09-300001552000mplx:MPLXLPMember2023-12-310001552000mplx:MarkWestMember2024-09-300001552000mplx:MarkWestMember2023-12-310001552000mplx:ANDXLPMember2024-09-300001552000mplx:ANDXLPMember2023-12-310001552000mplx:MPLXRevolvingCreditFacilityDueJuly2027Member2024-09-300001552000mplx:MPLXRevolvingCreditFacilityDueJuly2027Member2024-01-012024-09-300001552000srt:MinimumMemberus-gaap:SeniorNotesMember2024-09-300001552000srt:MaximumMemberus-gaap:SeniorNotesMember2024-09-300001552000mplx:SeniorNoteDueJune2034Domainus-gaap:SeniorNotesMember2024-05-202024-05-200001552000mplx:SeniorNoteDueJune2034Domainus-gaap:SeniorNotesMember2024-05-200001552000mplx:SeniorNotesDueDecember2024Membermplx:MPLXLPMemberus-gaap:SeniorNotesMember2024-09-300001552000mplx:SeniorNotesDueDecember2024Membermplx:MarkWestMemberus-gaap:SeniorNotesMember2024-09-300001552000mplx:SeniorNotesDueFebruary2025Membermplx:MPLXLPMemberus-gaap:SeniorNotesMember2024-09-300001552000us-gaap:ServiceMembermplx:LogisticsandStorageMember2024-07-012024-09-300001552000us-gaap:ServiceMembermplx:GatheringandProcessingMember2024-07-012024-09-300001552000us-gaap:ServiceOtherMembermplx:LogisticsandStorageMember2024-07-012024-09-300001552000us-gaap:ServiceOtherMembermplx:GatheringandProcessingMember2024-07-012024-09-300001552000us-gaap:ProductMembermplx:LogisticsandStorageMember2024-07-012024-09-300001552000us-gaap:ProductMembermplx:GatheringandProcessingMember2024-07-012024-09-300001552000us-gaap:ServiceMembermplx:LogisticsandStorageMember2023-07-012023-09-300001552000us-gaap:ServiceMembermplx:GatheringandProcessingMember2023-07-012023-09-300001552000us-gaap:ServiceOtherMembermplx:LogisticsandStorageMember2023-07-012023-09-300001552000us-gaap:ServiceOtherMembermplx:GatheringandProcessingMember2023-07-012023-09-300001552000us-gaap:ProductMembermplx:LogisticsandStorageMember2023-07-012023-09-300001552000us-gaap:ProductMembermplx:GatheringandProcessingMember2023-07-012023-09-300001552000us-gaap:ServiceMembermplx:LogisticsandStorageMember2024-01-012024-09-300001552000us-gaap:ServiceMembermplx:GatheringandProcessingMember2024-01-012024-09-300001552000us-gaap:ServiceOtherMembermplx:LogisticsandStorageMember2024-01-012024-09-300001552000us-gaap:ServiceOtherMembermplx:GatheringandProcessingMember2024-01-012024-09-300001552000us-gaap:ProductMembermplx:LogisticsandStorageMember2024-01-012024-09-300001552000us-gaap:ProductMembermplx:GatheringandProcessingMember2024-01-012024-09-300001552000us-gaap:ServiceMembermplx:LogisticsandStorageMember2023-01-012023-09-300001552000us-gaap:ServiceMembermplx:GatheringandProcessingMember2023-01-012023-09-300001552000us-gaap:ServiceOtherMembermplx:LogisticsandStorageMember2023-01-012023-09-300001552000us-gaap:ServiceOtherMembermplx:GatheringandProcessingMember2023-01-012023-09-300001552000us-gaap:ProductMembermplx:LogisticsandStorageMember2023-01-012023-09-300001552000us-gaap:ProductMembermplx:GatheringandProcessingMember2023-01-012023-09-300001552000us-gaap:NonrelatedPartyMember2022-12-310001552000us-gaap:NonrelatedPartyMember2023-09-300001552000us-gaap:RelatedPartyMember2022-12-310001552000us-gaap:RelatedPartyMember2023-09-3000015520002024-10-012024-09-3000015520002025-01-012024-09-3000015520002026-01-012024-09-3000015520002027-01-012024-09-3000015520002028-01-012024-09-3000015520002029-01-012024-09-300001552000srt:MaximumMember2024-09-3000015520002020-07-012020-07-3100015520002020-12-152020-12-150001552000mplx:BakkenPipelineSystemMemberus-gaap:GuaranteeOfIndebtednessOfOthersMemberus-gaap:FinancialGuaranteeMember2024-09-300001552000mplx:WPCParentLLCMemberus-gaap:PerformanceGuaranteeMember2024-09-30
目錄
美國
證券交易委員會
華盛頓特區20549
 _____________________________________________
表格 10-Q
 ____________________________________________
(標記一)
根據1934年證券交易法第13或15(d)節的季度報告
截至季度結束日期的財務報告2024年9月30日
OR
根據1934年證券交易法第13或15(d)節的轉型報告書
過渡期從                                        
佣金文件號 001-35714
_____________________________________________ 
MPLX LP
(根據其章程規定的註冊人準確名稱)
 _____________________________________________
特拉華州27-0005456
(國家或其他管轄區的
公司成立或組織)
 (IRS僱主
唯一識別號碼)
200 E. Hardin Street,Findlay,俄亥俄州 45840
,(主要行政辦公地址)(郵政編碼)
(419) 422-2121
(註冊人電話號碼,包括區號)
 _____________________________________________
根據法案第12(b)條註冊證券
每一類的名稱交易標的在其上註冊的交易所的名稱
普通單位代表有限合夥權益MPLX請使用moomoo賬號登錄查看New York Stock Exchange
請在以下方框內打勾,表示報告人(1)在過去12個月內(或報告人所需被要求提交這些報告的較短期間內,如果有)已經提交了所有根據1934年證券交易法第13或15(d)節規定所需提交的報告, 並且(2)在過去90天內一直受到此類提交要求的約束。  

請在以下勾選方框表示註冊人是否已在Regulation S-T Rule 405規定的前12個月(或在註冊人需要提交此類文件的較短期間內)提交了每個互動數據文件。      否  

√ 大型快速歸檔人   √加速歸檔人   √非加速歸檔人   ¨較小報告公司   ¨新興成長型公司 請參見《交易所法》第12億.2條中對「大型快速歸檔人」、「加速歸檔人」、「較小的報告公司」和「新興成長型公司」的定義。
大型加速報告人加速文件申報人未加速的報告人
更小的報告公司
新興成長公司

如果新興成長公司,根據交易所法案13(a)條款,表明是否選擇不使用延長過渡期來遵守任何新的或修訂的財務會計準則。

請勾選:註冊人是否爲外殼公司(根據《交易所法案》120億.2規定定義)。是     否  

截至2024年7月31日,mplx lp共有1,020,584,538個普通單位。 1,018,812,097 截至2024年10月31日,普通單位未償還


目錄
項目2.
 
項目1。
項目4.
項目1.
項目2.
除非另有說明或上下文另有說明,否則本10-Q表單中對「馬拉松原油」,「MPLX」,「合夥企業」,「我們」,「我們的」“我們,或類似術語的所有參考均指MPLX LP及其合併子公司。對我們的贊助商和客戶「MPC」的引用,除了合夥企業外,還指其子公司馬拉松石油公司。
1A項目。
本報告中使用的縮寫,首字母縮略詞和行業術語的定義如下:
項目5。
項目6。
一桶原油,或42美加侖的液體體積,用於原油或其他液態碳氫化合物的參考。
1

目錄
術語表
本報告中使用的縮略語、首字母縮寫和行業術語定義如下:
ASC會計準則編纂
ASU會計準則更新
一個儲罐桶,即 42 美國加侖的液體容量,用於表示原油或其他液態碳氫化合物
DCF(非公認會計准則財務指標)可分配現金流
息稅折舊攤銷前利潤(非公認會計准則財務指標)扣除利息、稅項、折舊和攤銷前的收益
FASB財務會計準則委員會
GAAP美利堅合衆國普遍接受的會計原則
G&P收集和處理部分
L&S物流和倉儲部門
mbpd每天一千桶
mmBTU一百萬英制熱單位,能量測量
mmcf/D每天一百萬立方英尺
NGL液態天然氣,例如乙烷、丙烷、丁烷和天然汽油
美國證券交易委員會
軟弱有擔保的隔夜融資利率
競爭可變利益實體

2

目錄
第一部分——財務信息
項目1:基本報表
mplx lp
綜合損益表(未經審計)
截至2022年1月31日三個月的期間結束
September 30,
九個月截至
September 30,
(以百萬美元爲單位,除每單位數據外)2024202320242023
收入和其他收入:
服務收入$709 $641 $2,050 $1,881 
服務收入 - 關聯方1,066 1,038 3,102 2,962 
服務收入 - 產品相關86 75 265 214 
租賃收入63 61 187 181 
出租收入 - 關聯方216 207 644 612 
產品銷售433 478 1,191 1,274 
產品銷售 - 關聯方51 51 164 155 
銷售型租賃收入34 34 102 101 
銷售類型租賃收入 - 關聯方118 129 359 379 
股權法下投資收益149 159 631 438 
其他收入7 7 58 28 
其他收入 - 關聯方40 32 117 90 
總收入和其他收入2,972 2,912 8,870 8,315 
成本和費用:
營業成本(不包括以下項目)404 367 1,159 1,023 
購買產品成本403 474 1,148 1,234 
租賃成本銷售額22 20 61 60 
銷售租賃成本-關聯方5 8 14 24 
採購-關聯方402 442 1,162 1,160 
折舊和攤銷322 301 959 907 
一般及管理費用107 102 323 280 
其他稅費32 44 99 102 
總成本和費用1,697 1,758 4,925 4,790 
營業利潤1,275 1,154 3,945 3,525 
淨利息及其他金融成本226 225 692 701 
稅前收入1,049 929 3,253 2,824 
所得稅費用2 1 5 2 
淨收入1,047 928 3,248 2,822 
淨利潤歸屬於非控制權益10 10 30 28 
歸屬於mplx lp的淨利潤1,037 918 3,218 2,794 
減:A級優先單位持有人的淨利潤權益6 25 21 71 
減:B級優先單位持有人的淨利潤權益   5 
有限合夥人持有的歸屬於mplx lp的淨利潤權益$1,031 $893 $3,197 $2,718 
單位數據(見注7)
歸屬於mplx lp的淨利潤每個有限合夥人單位:
普通-基本$1.01 $0.89 $3.14 $2.70 
普通-攤薄$1.01 $0.89 $3.14 $2.70 
加權平均持股有限合夥人單位數:
普通股-基本1,020 1,001 1,016 1,001 
普通股-稀釋1,020 1,001 1,016 1,001 
The accompanying notes are an integral part of these consolidated financial statements.
3

Table of Contents
MPLX LP
Consolidated Statements of Comprehensive Income (Unaudited)
Three Months Ended 
September 30,
Nine Months Ended 
September 30,
(In millions)2024202320242023
Net income$1,047 $928 $3,248 $2,822 
Other comprehensive income, net of tax:
Remeasurements of pension and other postretirement benefits related to equity method investments, net of tax  1 4 
Comprehensive income1,047 928 3,249 2,826 
Less comprehensive income attributable to:
Noncontrolling interests10 10 30 28 
Comprehensive income attributable to MPLX LP$1,037 $918 $3,219 $2,798 
The accompanying notes are an integral part of these consolidated financial statements.
4

Table of Contents
MPLX LP
Consolidated Balance Sheets (Unaudited)
(In millions)September 30,
2024
December 31,
2023
Assets
Cash and cash equivalents$2,426 $1,048 
Receivables, net742 823 
Current assets - related parties842 748 
Inventories171 159 
Other current assets37 30 
Total current assets4,218 2,808 
Equity method investments4,558 3,743 
Property, plant and equipment, net19,153 19,264 
Intangibles, net551 654 
Goodwill7,645 7,645 
Right of use assets, net271 264 
Noncurrent assets - related parties1,135 1,161 
Other noncurrent assets984 990 
Total assets38,515 36,529 
Liabilities
Accounts payable120 153 
Accrued liabilities271 300 
Current liabilities - related parties354 360 
Accrued property, plant and equipment190 216 
Long-term debt due within one year2,836 1,135 
Accrued interest payable220 242 
Operating lease liabilities49 45 
Other current liabilities227 173 
Total current liabilities4,267 2,624 
Long-term deferred revenue326 347 
Long-term liabilities - related parties320 325 
Long-term debt19,250 19,296 
Deferred income taxes16 16 
Long-term operating lease liabilities217 211 
Other long-term liabilities137 126 
Total liabilities24,533 22,945 
Commitments and contingencies (see Note 16)
Series A preferred units (6 million and 27 million units outstanding)
203 895 
Equity
Common unitholders - public (372 million and 356 million units outstanding)
9,378 8,700 
Common unitholders - MPC (647 million and 647 million units outstanding)
4,172 3,758 
Accumulated other comprehensive loss(3)(4)
Total MPLX LP partners’ capital13,547 12,454 
Noncontrolling interests232 235 
Total equity13,779 12,689 
Total liabilities, preferred units and equity$38,515 $36,529 
The accompanying notes are an integral part of these consolidated financial statements.
5

Table of Contents
MPLX LP
Consolidated Statements of Cash Flows (Unaudited)
Nine Months Ended 
September 30,
(In millions)20242023
Operating activities:
Net income$3,248 $2,822 
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of deferred financing costs41 42 
Depreciation and amortization959 907 
Deferred income taxes (1)
Gain on sales-type leases and equity method investments(20) 
Loss/(gain) on disposal of assets3 (15)
Income from equity method investments(631)(438)
Distributions from unconsolidated affiliates596 526 
Change in fair value of derivatives7 (3)
Changes in:
Receivables138 (31)
Inventories(11)(15)
Current accounts payable and other current assets and liabilities(54)(36)
Assets and liabilities - related parties(23)89 
Right of use assets and operating lease liabilities3 4 
Deferred revenue2 65 
All other, net13 (8)
Net cash provided by operating activities4,271 3,908 
Investing activities:
Additions to property, plant and equipment(748)(662)
Acquisitions, net of cash acquired(622) 
Disposal of assets 25 
Investments - acquisitions and contributions(414)(90)
- redemptions, repayments, return of capital and sales proceeds138  
Net cash used in investing activities(1,646)(727)
Financing activities:
Long-term debt borrowings1,630 1,589 
Long-term debt repayments(1)(1,001)
Debt issuance costs(15)(15)
Unit repurchases(226) 
Redemption of Series B preferred units (600)
Distributions to noncontrolling interests(33)(30)
Distributions to Series A preferred unitholders(38)(69)
Distributions to Series B preferred unitholders (21)
Distributions to unitholders and general partner(2,585)(2,329)
Contributions from MPC26 20 
All other, net(5)(3)
Net cash used in financing activities(1,247)(2,459)
Net change in cash, cash equivalents and restricted cash1,378 722 
Cash, cash equivalents and restricted cash at beginning of period1,048 238 
Cash, cash equivalents and restricted cash at end of period$2,426 $960 
The accompanying notes are an integral part of these consolidated financial statements.
6

Table of Contents
MPLX LP
Consolidated Statements of Equity and Series A Preferred Units (Unaudited)
 Partnership  
(In millions)Common
Unit-holders
Public
Common
Unit-holder
MPC
Accumulated Other Comprehensive LossNon-controlling
Interests
TotalSeries A Preferred Unit-holders
Balance at December 31, 2023$8,700 $3,758 $(4)$235 $12,689 $895 
Net income355 640  10 1,005 10 
Unit repurchases(75)   (75)— 
Conversion of Series A preferred units321    321 (321)
Distributions(303)(550) (11)(864)(23)
Contributions 10   10 — 
Other(1) 1   — 
Balance at March 31, 2024$8,997 $3,858 $(3)$234 $13,086 $561 
Net income425 746  10 1,181 5 
Unit repurchases(75)   (75)— 
Conversion of Series A preferred units354    354 (354)
Distributions(314)(550) (11)(875)(10)
Contributions 8   8 — 
Other5    5 — 
Balance at June 30, 2024$9,392 $4,062 $(3)$233 $13,684 $202 
Net income377 654  10 1,041 6 
Unit repurchases(76)   (76)— 
Distributions(317)(551) (11)(879)(5)
Contributions 7   7 — 
Other2    2 — 
Balance at September 30, 2024$9,378 $4,172 $(3)$232 $13,779 $203 
Partnership
Common
Unit-holders
Public
Common
Unit-holder
MPC
Series B Preferred Unit-holdersAccumulated Other Comprehensive LossNon-controlling
Interests
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 
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 
The accompanying notes are an integral part of these consolidated financial statements.
7

Table of Contents
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 8 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, 2023. The results of operations for the three and nine months ended September 30, 2024 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.
Certain prior period financial statement amounts have been reclassified to conform to current period presentation.
2. Accounting Standards and Disclosure Rules
Recently Adopted
During the first quarter of 2024, we adopted ASU 2023-01, Leases (Topic 842): Common Control Arrangements. The adoption of this ASU did not have a material impact on our financial statements or disclosures.
Not Yet Adopted
ASU 2024-03, Income Statement – Reporting Comprehensive Income – Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses
In November 2024, the FASB issued an ASU to require more detailed information about specified categories of expenses (purchases of inventory, employee compensation, depreciation, amortization, and depletion) included in certain expense captions presented on the face of the income statement. This ASU is effective for fiscal years beginning after December 15, 2026, and for interim periods within fiscal years beginning after December 15, 2027. Early adoption is permitted. The amendments may be applied either (1) prospectively to financial statements issued for reporting periods after the effective date of this ASU or (2) retrospectively to all prior periods presented in the financial statements. We are currently evaluating the impact this ASU will have on our disclosures.

SEC Release No. 33-11275, The Enhancement and Standardization of Climate-Related Disclosures for Investors
In March 2024, the SEC adopted rules under SEC Release No. 33-11275, The Enhancement and Standardization of Climate-Related Disclosures for Investors, which requires registrants to provide certain climate-related information in their annual reports. As part of the disclosures, material impacts from severe weather events and other natural conditions will be required in the audited financial statements. In April 2024, the SEC voluntarily stayed the rules pending judicial review. Pending the results of
8

Table of Contents
the judicial review, the disclosure requirements are effective for the Partnership’s Annual Report on Form 10-K for the fiscal year ending December 31, 2025. We are evaluating the impact these rules will have on our disclosures and monitoring the status of the judicial review.
ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures
In November 2023, the FASB issued an ASU to update reportable segment disclosure requirements primarily by requiring enhanced disclosures about significant segment expenses. This ASU is effective for fiscal years beginning after December 15, 2023, and for interim periods within fiscal years beginning after December 15, 2024. Early adoption is permitted. The amendments should be applied retrospectively to all prior periods presented in the financial statements. This standard will have no impact on the Partnership’s financial statements, but will result in additional disclosure.
3. Acquisitions and Other Transactions
BANGL, LLC Acquisition
On July 31, 2024, MPLX exercised its right of first offer under the BANGL, LLC joint venture agreement to purchase an additional 20 percent ownership interest in BANGL, LLC, for $210 million cash, increasing total ownership interest to 45 percent (the “BANGL Transaction”). BANGL is a natural gas liquids pipeline system connecting the Delaware and Midland basins to the fractionation market in Sweeny, Texas. The purchase price of the additional 20 percent ownership interest in BANGL, LLC exceeded our portion of the underlying net assets of the joint venture by approximately $156 million. This basis difference is being amortized into net income over the remaining estimated useful lives of the underlying net assets. Following the BANGL Transaction, our investment in BANGL, LLC continues to be accounted for as an equity method investment.
Whistler Joint Venture Transaction
On May 29, 2024, MPLX and its joint venture partner contributed their respective membership interest in Whistler Pipeline, LLC to a newly formed joint venture, WPC Parent, LLC, and issued a 19 percent voting interest in WPC Parent, LLC to an affiliate of Enbridge Inc. in exchange for the contribution of cash and the Rio Bravo Pipeline project. As a result of the transaction, MPLX’s voting interest in the joint venture was reduced from 37.5 percent to 30.4 percent. MPLX recognized a gain of $151 million and received a cash distribution of $134 million, recorded as a return of capital, related to the dilution of the ownership interest. The gain is included in Income from equity method investments on the accompanying consolidated statements of income and the return of capital is included in Investments - redemptions, repayments, return of capital and sales proceeds within the investing section of the accompanying consolidated statements of cash flows.
Utica Midstream Acquisition
On March 22, 2024, MPLX used $625 million of cash on hand to purchase additional ownership interest in existing joint ventures and gathering assets (the “Utica Midstream Acquisition”), which will enhance our position in the Utica basin. Prior to the acquisition, we owned an indirect interest in Ohio Gathering Company L.L.C. (“OGC”) and a direct interest in Ohio Condensate Company L.L.C. (“OCC”) and now own a combined 73 percent interest in OGC, a 100 percent interest in OCC, and a 100 percent interest in a dry gas gathering system in the Utica basin, including 53 miles of gathering pipeline and three dehydration units with a combined capacity of approximately 620 MMcf/d. OGC continues to be accounted for as an equity method investment, as MPLX did not obtain control of OGC as a result of the transaction. The acquisition date fair value of our investment in OGC exceeded our portion of the underlying net assets of the joint venture by approximately $86 million. This basis difference is being amortized into net income over the remaining estimated useful lives of the underlying net assets. OCC was previously accounted for as an equity method investment, and it is now reflected as a consolidated subsidiary within our consolidated financial results. The results for the acquired business are reported within our G&P segment.
The Utica Midstream Acquisition was accounted for as a business combination requiring all the acquired assets and liabilities to be remeasured to fair value resulting in a consolidated fair value of net assets and liabilities of $625 million. The fair value includes $518 million related to acquired interests in the joint ventures and the remaining balance related to other acquired assets and liabilities. The revaluation of MPLX’s existing 62 percent equity method investment in OCC resulted in a $20 million gain, which is included in Other income within the accompanying consolidated statements of income. The fair value of equity method investments was based on a discounted cash flow model.
9

Table of Contents
4. 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)VIE202420242023
L&S
BANGL, LLC(1)
45%$275 $63 
Illinois Extension Pipeline Company, L.L.C.35%231 228 
LOOP LLC41%313 314 
MarEn Bakken Company LLC(2)
25%530 449 
WPC Parent, LLC(3)
30%206 214 
Other(4)
X593 564 
Total L&S2,148 1,832 
G&P
MarkWest EMG Jefferson Dry Gas Gathering Company, L.L.CX67%335 336 
MarkWest Utica EMG, L.L.C.X59%717 676 
Ohio Gathering Company L.L.C.(5)
X35%488  
Sherwood Midstream LLCX50%492 500 
Other(4)
X378 399 
Total G&P2,410 1,911 
Total$4,558 $3,743 
(1)    In July 2024, we purchased an additional 20 percent ownership interest in BANGL, LLC, increasing our ownership interest to 45 percent, as discussed in Note 3.
(2)    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, the “Bakken Pipeline system”).    
(3)    Reflects the dilution of MPLX’s ownership interest in Whistler Pipeline, LLC and the formation of a new entity, WPC Parent, LLC, as discussed in Note 3. The carrying value at September 30, 2024 represents our ownership in WPC Parent, LLC, and the carrying value at December 31, 2023 represents our ownership interest in Whistler Pipeline, LLC.
(4)    Some investments included within Other have also been deemed to be VIEs.
(5)    We acquired a 36 percent direct interest in OGC in the Utica Midstream Acquisition discussed in Note 3. We also hold a 38 percent indirect interest in OGC through our ownership interest in MarkWest Utica EMG, L.L.C.
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 generally 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, 2024 and September 30, 2023. See Note 16 for information on our guarantees related to equity method investees.
5. 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 agreements. 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 we pay MPC a marketing fee in exchange for assuming the commodity risk. In addition, MPLX has obligations to MPC for services provided to MPLX by MPC under omnibus and employee services type agreements as well as various other agreements.
10

Table of Contents
During the second quarter of 2024, MPC exercised a five-year renewal option pursuant to the terms of an existing terminal services agreement with an initial term ending on March 31, 2026, with the term of the agreement now extending to 2031.The agreement includes both revenue and lease components. At the time of renewal, minimum future rental payments on non-cancellable operating leases increased $696 million, and minimum future undiscounted lease payment receipts under sales-type leases increased $90 million. Future performance obligations for the revenue component of the agreement include variable consideration that is not required to be estimated.
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 was renewed on July 31, 2024 and is now scheduled to expire, and borrowings under the loan agreement are scheduled to mature and become due and payable, on July 31, 2029, 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 12.
There was no activity on the MPC Loan Agreement for the nine months ended September 30, 2024.
Related Party Revenue
Related party sales to MPC primarily consist of crude oil and refined products pipeline services 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, 2024, these sales totaled $177 million and $561 million, respectively. For the three and nine months ended September 30, 2023, these sales totaled $192 million and $540 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, 2024, General and administrative expenses incurred from MPC totaled $73 million and $217 million, respectively. For the three and nine months ended September 30, 2023, General and administrative expenses incurred from MPC totaled $72 million and $197 million, respectively.
Some charges incurred under the omnibus, employee service and co-location agreements are related to engineering and construction 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, 2024, these charges totaled $44 million and $124 million, respectively. For the three and nine months ended September 30, 2023, these charges totaled $28 million and $56 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. If MPC fails to meet its minimum committed volumes, MPC will pay MPLX a deficiency payment based on the terms of the applicable 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
11

Table of Contents
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,
2024
December 31,
2023
Current assets - related parties
Receivables$625 $587 
Lease receivables203 149 
Prepaid14 5 
Other 7 
Total842 748 
Noncurrent assets - related parties
Long-term lease receivables711 789 
Right of use assets226 227 
Unguaranteed residual asset172 126 
Long-term receivables26 19 
Total1,135 1,161 
Current liabilities - related parties
MPC Loan Agreement and other payables(1)
264 278 
Deferred revenue89 81 
Operating lease liabilities1 1 
Total354 360 
Long-term liabilities - related parties
Long-term operating lease liabilities225 226 
Long-term deferred revenue95 99 
Total$320 $325 
(1)    There were no borrowings outstanding on the MPC Loan Agreement as of September 30, 2024 or December 31, 2023.
6. Equity
The changes in the number of common units during the nine months ended September 30, 2024 are summarized below:
(In units)Common Units
Balance at December 31, 20231,003,498,875 
Unit-based compensation awards141,985 
Conversion of Series A preferred units21,078,998 
Units redeemed in unit repurchase program(5,473,621)
Balance at September 30, 20241,019,246,237 
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 suspended, discontinued or restarted at any time.
Total unit repurchases were as follows for the respective periods:
Three Months Ended 
September 30,
Nine Months Ended 
September 30,
(In millions, except per unit data)2024202320242023
Number of common units repurchased1.8  5.5  
Cash paid for common units repurchased(1)
$76 $ $226 $ 
Average cost per unit(1)
$42.89 $ $41.32 $ 
(1)    Cash paid for common units repurchased and average cost per unit includes commissions paid to brokers during the period.
12

Table of Contents
As of September 30, 2024, we had $620 million remaining under the unit repurchase authorization.
Series A Redeemable Preferred Unit Conversions
During the nine months ended September 30, 2024, certain Series A preferred unitholders exercised their rights to convert their Series A preferred units into approximately 21 million common units. Approximately 6 million Series A preferred units remain outstanding as of September 30, 2024.
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. MPLX made a final cash distribution of $21 million to Series B preferred unitholders on February 15, 2023, in conjunction with the redemption.
Distributions
On October 29, 2024, MPLX declared a cash distribution for the third quarter of 2024, totaling $974 million, or $0.9565 per common unit. This distribution will be paid on November 15, 2024 to common unitholders of record on November 8, 2024. This rate will also be received by Series A preferred unitholders.
Quarterly distributions for 2024 and 2023 are summarized below:
(Per common unit)20242023
March 31,$0.8500 $0.7750 
June 30,0.8500 0.7750 
September 30,$0.9565 $0.8500 
The allocation of total quarterly cash distributions to common and preferred unitholders is as follows for the three and nine months ended September 30, 2024 and September 30, 2023. 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)2024202320242023
Common and preferred unit distributions:
Common unitholders, includes common units of general partner$974 $851 $2,706 $2,403 
Series A preferred unit distributions6 25 21 71 
Series B preferred unit distributions(1)
   5 
Total cash distributions declared$980 $876 $2,727 $2,479 
(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.
7. 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, 2024 and September 30, 2023, 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, 2024 and September 30, 2023 were less than 1 million.
13

Table of Contents
Three Months Ended 
September 30,
Nine Months Ended 
September 30,
(In millions, except per unit data)2024202320242023
Net income attributable to MPLX LP(1):
$1,037 $918 $3,218 $2,794 
Less: Distributions declared on Series A preferred units6 25 21 71 
Distributions declared on Series B preferred units   5 
Undistributed earnings allocated to participating securities 1 7 9 
Impact of redemption of Series B preferred units   5 
Net Income available to common unitholders$1,031 $892 $3,190 $2,704 
Weighted average units outstanding:
Basic1,020 1,001 1,016 1,001 
Diluted1,020 1,001 1,016 1,001 
Net income attributable to MPLX LP per limited partner unit:
Basic$1.01 $0.89 $3.14 $2.70 
Diluted$1.01 $0.89 $3.14 $2.70 
(1)    Allocation of net income attributable to MPLX LP assumes all earnings for the period have been distributed based on the distribution priorities applicable to the period.
8. 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) net interest and other financial costs; (iii) income/(loss) from equity method investments; (iv) distributions and adjustments related to equity method investments; (v) impairment expense; (vi) noncontrolling interests; and (vii) 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.
14

Table of Contents
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)2024202320242023
L&S
Service revenue$1,158 $1,130 $3,367 $3,223 
Rental income223 216 666 638 
Product related revenue5 6 14 14 
Sales-type lease revenue118 129 359 379 
Income from equity method investments80 95 429 248 
Other income33 15 113 47 
Total segment revenues and other income(1)
1,617 1,591 4,948 4,549 
Segment Adjusted EBITDA(2)
1,157 1,091 3,384 3,139 
Capital expenditures112 73 299 251 
Investments in unconsolidated affiliates(3)
10 7 103 23 
G&P
Service revenue617 549 1,785 1,620 
Rental income56 52 165 155 
Product related revenue565 598 1,606 1,629 
Sales-type lease revenue 34 34 102 101 
Income from equity method investments69 64 202 190 
Other income14 24 62 71 
Total segment revenues and other income(1)
1,355 1,321 3,922 3,766 
Segment Adjusted EBITDA(2)
557 505 1,618 1,507 
Capital expenditures189 151 421 417 
Investments in unconsolidated affiliates$22 $6 $83 $67 
(1)    Within the total segment revenues and other income amounts presented above, third party revenues for the L&S segment were $196 million and $779 million for the three and nine months ended September 30, 2024, respectively, and $207 million and $564 million for the three and nine months ended September 30, 2023, respectively. Third party revenues for the G&P segment were $1,285 million and $3,705 million for the three and nine months ended September 30, 2024, respectively, and $1,248 million and $3,553 million for the three and nine months ended September 30, 2023, respectively.
(2)    See below for the reconciliation from Segment Adjusted EBITDA to Net income.
(3)    The nine months ended September 30, 2024 includes a contribution of $92 million to Dakota Access to fund our share of a debt repayment by the joint venture.
15

Table of Contents
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)2024202320242023
Reconciliation to Net income:
L&S Segment Adjusted EBITDA$1,157 $1,091 $3,384 $3,139 
G&P Segment Adjusted EBITDA557 505 1,618 1,507 
Total reportable segments1,714 1,596 5,002 4,646 
Depreciation and amortization(1)
(322)(301)(959)(907)
Net interest and other financial costs(226)(225)(692)(701)
Income from equity method investments149 159 631 438 
Distributions/adjustments related to equity method investments(253)(208)(671)(551)
Adjusted EBITDA attributable to noncontrolling interests11 11 33 31 
Garyville incident response costs(2)
 (63) (63)
Other(3)
(26)(41)(96)(71)
Net income$1,047 $928 $3,248 $2,822 
(1)    Depreciation and amortization attributable to L&S was $132 million and $393 million for the three and nine months ended September 30, 2024, respectively, and $130 million and $399 million for the three and nine months ended September 30, 2023, respectively. Depreciation and amortization attributable to G&P was $190 million and $566 million for the three and nine months ended September 30, 2024, respectively, and $171 million and $508 million for the three and nine months ended September 30, 2023, 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), equity-based compensation, provision for income taxes, and other miscellaneous items.
9. Property, Plant and Equipment
Property, plant and equipment with associated accumulated depreciation is shown below:
September 30, 2024December 31, 2023
(In millions)Gross PP&EAccumulated DepreciationNet PP&EGross PP&EAccumulated DepreciationNet PP&E
L&S $13,037 $4,421 $8,616 $12,779 $4,037 $8,742 
G&P 15,087 4,550 10,537 14,606 4,084 10,522 
Total$28,124 $8,971 $19,153 $27,385 $8,121 $19,264 
10. 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, 2024 and December 31, 2023 by fair value hierarchy level.
September 30, 2024December 31, 2023
(In millions)AssetLiabilityAssetLiability
Commodity contracts (Level 2)
Other current assets / Other current liabilities$1 $ $ $ 
Embedded derivatives in commodity contracts (Level 3)
Other current assets / Other current liabilities 10  11 
Other noncurrent assets / Other long-term liabilities 59  50 
Total carrying value in Consolidated Balance Sheets$1 $69 $ $61 
Level 2 instruments include over-the-counter fixed swaps to mitigate the price risk from our sales of propane under certain percent-of-proceeds and keep-whole arrangements. The swap valuations are based on observable inputs in the form of forward prices based on Mont Belvieu propane forward spot prices and contain no significant unobservable inputs.
Level 3 instruments relate to an embedded derivative liability for a natural gas purchase commitment embedded in a keep-whole processing agreement. The fair value calculation for these Level 3 instruments used significant unobservable inputs including: (1) NGL prices interpolated and extrapolated due to inactive markets ranging from $0.67 to $1.45 per gallon with a weighted average
16

Table of Contents
of $0.85 per gallon and (2) a 100 percent probability of renewal for the five-year renewal term of the gas purchase commitment and related keep-whole processing agreement. Increases or decreases in the fractionation spread result in an increase or decrease in the fair value of the embedded derivative liability, respectively.
Changes in Level 3 Fair Value Measurements
The following table is a reconciliation of the net beginning and ending balances recorded for net liabilities classified as Level 3 in the fair value hierarchy.
Three Months Ended 
September 30,
Nine Months Ended 
September 30,
(In millions)2024202320242023
Beginning balance $(69)$(53)$(61)$(61)
Unrealized and realized (loss)/gain included in Net Income(1)
(3)(10)(18)(7)
Settlements3 3 10 8 
Ending balance$(69)$(60)$(69)$(60)
The amount of total loss for the period included in earnings attributable to the change in unrealized (loss)/gain relating to liabilities still held at end of period$(3)$(9)$(15)$(6)
(1)    (Loss)/gain on derivatives embedded in commodity contracts are recorded in Purchased product costs in the Consolidated Statements of Income.
Fair Values – Non-recurring
Non-recurring fair value measurements and disclosures in 2024 relate to acquisitions and other transactions as discussed in Note 3.
Fair Values – Reported
We believe the carrying value of our other financial instruments, including cash and cash equivalents, receivables, receivables from related parties, lease receivables, lease receivables from related parties, accounts payable, and payables to related parties, approximate fair value. MPLX’s fair value assessment incorporates a variety of considerations, including the duration of the instruments, MPC’s investment-grade credit rating, and the historical incurrence of and expected future insignificance of bad debt expense, which includes an evaluation of counterparty credit risk. The recorded value of the amounts outstanding under the bank revolving credit facility, if any, approximates fair value due to the variable interest rate that approximates current market rates. Derivative instruments are recorded at fair value, based on available market information (see Note 11).
The fair value of MPLX’s debt is estimated based on prices from recent trade activity and is categorized in Level 3 of the fair value hierarchy. The following table summarizes the fair value and carrying value of our third-party debt, excluding finance leases and unamortized debt issuance costs:
September 30, 2024December 31, 2023
(In millions)Fair ValueCarrying ValueFair ValueCarrying Value
Outstanding debt(1)
$21,494 $22,209 $19,377 $20,547 
(1)    Any amounts outstanding under the MPC Loan Agreement are not included in the table above, as the carrying value approximates fair value. This balance is reflected in Current liabilities - related parties in the Consolidated Balance Sheets.
11. Derivatives
As of September 30, 2024, MPLX had the following outstanding commodity contracts that were executed to manage the price risk associated with sales of propane under certain percent-of-proceeds and keep-whole arrangements during 2024. Any gains or losses on these contracts are recorded in earnings through Product sales in the Consolidated Statements of Income:
Derivative contracts not designated as hedging instrumentsFinancial PositionNotional Quantity
Propane (gal)Short14,427,000 
Embedded Derivative - MPLX has a natural gas purchase commitment embedded in a keep-whole processing agreement with a producer customer in the Southern Appalachia region expiring in December 2027. The customer has the unilateral option to extend the agreement for one five-year term through December 2032. For accounting purposes, the natural gas purchase commitment and the term extending option have been aggregated into a single compound embedded derivative. The probability of the customer exercising its option is determined based on assumptions about the customer’s potential business strategy decision points that may exist at the time they would elect whether to renew the contract. The changes in fair value of this
17

Table of Contents
compound embedded derivative are based on the difference between the contractual and index pricing, the probability of the producer customer exercising its option to extend, and the estimated favorability of these contracts compared to current market conditions. The changes in fair value are recorded in earnings through Purchased product costs in the Consolidated Statements of Income. For further information regarding the fair value measurement of derivative instruments, see Note 10. As of September 30, 2024 and December 31, 2023, the estimated fair value of this contract was a liability of $69 million and $61 million, respectively.
Certain derivative positions are subject to master netting agreements; therefore, MPLX has elected to offset derivative assets and liabilities that are legally permissible to be offset. As of September 30, 2024 and December 31, 2023, there were no derivative assets or liabilities that were offset in the Consolidated Balance Sheets.
We make a distinction between realized or unrealized gains and losses on derivatives. During the period when a derivative contract is outstanding, changes in the fair value of the derivative are recorded as an unrealized gain or loss. When a derivative contract matures or is settled, the previously recorded unrealized gain or loss is reversed, and the realized gain or loss of the contract is recorded. The impact of MPLX’s derivative contracts not designated as hedging instruments and the location of gains and losses recognized in the Consolidated Statements of Income is summarized below:
Three Months Ended 
September 30,
Nine Months Ended 
September 30,
(In millions)2024202320242023
Product sales:
Realized gain$1 $3 $1 $3 
Unrealized gain/(loss)3 (8)1 2 
Product sales derivative gain/(loss)4 (5)2 5 
Purchased product costs:
Realized loss(3)(3)(10)(8)
Unrealized (loss)/gain (7)(8)1 
Purchased product cost derivative loss(3)(10)(18)(7)
Total derivative gain/(loss) included in Net income$1 $(15)$(16)$(2)
12. Debt
MPLX’s outstanding borrowings consist of the following:
(In millions)September 30,
2024
December 31,
2023
MPLX LP:
MPLX Credit Agreement$ $ 
Fixed rate senior notes22,307 20,657 
Consolidated subsidiaries:
MarkWest12 12 
ANDX31 31 
Finance lease obligations6 6 
Total22,356 20,706 
Unamortized debt issuance costs(129)(122)
Unamortized discount(141)(153)
Amounts due within one year(2,836)(1,135)
Total long-term debt due after one year$19,250 $19,296 
Credit Agreement
MPLX’s credit agreement (the “MPLX Credit Agreement”) matures in July 2027 and, among other things, provides for a $2 billion unsecured revolving credit facility and letter of credit issuing capacity under the facility of up to $150 million. Letter of credit issuing capacity is included in, not in addition to, the $2 billion borrowing capacity. Borrowings under the MPLX Credit Agreement bear interest, at MPLX’s election, at either the Adjusted Term SOFR or the Alternate Base Rate, both as defined in the MPLX Credit Agreement, plus an applicable margin.
There was no activity on the MPLX Credit Agreement during the nine months ended September 30, 2024.
18

Table of Contents
Fixed Rate Senior Notes
MPLX’s senior notes, including those issued by consolidated subsidiaries, consist of various series of senior notes maturing between 2024 and 2058 with interest rates ranging from 1.750 percent to 5.650 percent. Interest on each series of notes is payable semi-annually in arrears on various dates depending on the series of the notes.
On May 20, 2024, MPLX issued $1.65 billion aggregate principal amount of 5.50 percent senior notes due 2034 (the “2034 Senior Notes”) in an underwritten public offering. The 2034 Senior Notes were offered at a price to the public of 98.778 percent of par, with interest payable semi-annually in arrears, commencing on December 1, 2024. MPLX intends to use the net proceeds from the issuance of the 2034 Senior Notes to repay, redeem, or otherwise retire some or all of (i) MPLX’s outstanding $1,149 million aggregate principal amount of 4.875 percent senior notes due December 2024, (ii) MarkWest’s outstanding $1 million aggregate principal amount of 4.875 percent senior notes due December 2024 and (iii) MPLX’s outstanding $500 million aggregate principal amount of 4.000 percent senior notes due February 2025, and in the interim may use such net proceeds for general partnership purposes.
13. Net Interest and Other Financial Costs
Net interest and other financial costs were as follows:
Three Months Ended 
September 30,
Nine Months Ended 
September 30,
(In millions)2024202320242023
Interest expense$251 $227 $717 $684 
Other financial costs15 14 57 55 
Interest income(35)(12)(68)(27)
Capitalized interest(5)(4)(14)(11)
Net interest and other financial costs$226 $225 $692 $701 
14. Revenue
Disaggregation of Revenue
The following tables represent a disaggregation of revenue for each reportable segment for the three and nine months ended September 30, 2024 and September 30, 2023:
Three Months Ended September 30, 2024
(In millions)L&SG&PTotal
Revenues and other income:
Service revenue$101 $608 $709 
Service revenue - related parties1,057 9 1,066 
Service revenue - product related 86 86 
Product sales1 432 433 
Product sales - related parties4 47 51 
Total revenues from contracts with customers$1,163 $1,182 2,345 
Non-ASC 606 revenue(1)
627 
Total revenues and other income$2,972 
Three Months Ended September 30, 2023
(In millions)L&SG&PTotal
Revenues and other income:
Service revenue$97 $544 $641 
Service revenue - related parties1,033 5 1,038 
Service revenue - product related 75 75 
Product sales2 476 478 
Product sales - related parties4 47 51 
Total revenues from contracts with customers$1,136 $1,147 2,283 
Non-ASC 606 revenue(1)
629 
Total revenues and other income$2,912 
19

Table of Contents
Nine Months Ended September 30, 2024
(In millions)L&SG&PTotal
Revenues and other income:
Service revenue$286 $1,764 $2,050 
Service revenue - related parties3,081 21 3,102 
Service revenue - product related 265 265 
Product sales4 1,187 1,191 
Product sales - related parties10 154 164 
Total revenues from contracts with customers$3,381 $3,391 6,772 
Non-ASC 606 revenue(1)
2,098 
Total revenues and other income$8,870 
Nine Months Ended September 30, 2023
(In millions)L&SG&PTotal
Revenues and other income:
Service revenue$272 $1,609 $1,881 
Service revenue - related parties2,951 11 2,962 
Service revenue - product related 214 214 
Product sales4 1,270 1,274 
Product sales - related parties10 145 155 
Total revenues from contracts with customers$3,237 $3,249 6,486 
Non-ASC 606 revenue(1)
1,829 
Total revenues and other income$8,315 
(1)    Non-ASC 606 Revenue includes rental income, sales-type lease revenue, income from equity method investments, and other income.
Contract Balances
Our receivables are primarily associated with customer contracts. Payment terms vary by product or service type; however, the period between invoicing and payment is not significant. Included within the receivables are balances related to commodity sales on behalf of our producer customers, for which we remit the net sales price back to the producer customers upon completion of the sale.
Under certain of our contracts, we recognize revenues in excess of billings which we present as contract assets. Contract assets typically relate to deficiency payments related to minimum volume commitments and aid in construction agreements where the revenue recognized and MPLX’s rights to consideration for work completed exceeds the amount billed to the customer. Contract assets are included in Other current assets and Other noncurrent assets on the Consolidated Balance Sheets.
Under certain of our contracts, we receive payments in advance of satisfying our performance obligations, which are recorded as contract liabilities. Contract liabilities, which we present as Deferred revenue and Long-term deferred revenue, typically relate to advance payments for aid in construction agreements and deferred customer credits associated with makeup rights and minimum volume commitments. Related to minimum volume commitments, breakage is estimated and recognized into service revenue in instances where it is probable the customer will not use the credit in future periods. We classify contract liabilities as current or long-term based on the timing of when we expect to recognize revenue.
20

Table of Contents
The tables below reflect the changes in ASC 606 contract balances for the nine months ended September 30, 2024 and September 30, 2023:
(In millions)Balance at December 31, 2023Additions/ (Deletions)
Revenue Recognized(1)
Balance at September 30, 2024
Contract assets$3 $ $(1)$2 
Long-term contract assets1 (1)  
Deferred revenue59 65 (42)82 
Deferred revenue - related parties47 56 (50)53 
Long-term deferred revenue344 (22) 322 
Long-term deferred revenue - related parties$29 $5 $ $34 
(In millions)Balance at December 31, 2022Additions/ (Deletions)
Revenue Recognized(1)
Balance at September 30, 2023
Contract assets$21 $(19)$ $2 
Long-term contract assets1   1 
Deferred revenue57 24 (31)50 
Deferred revenue - related parties63 63 (72)54 
Long-term deferred revenue216 76  292 
Long-term deferred revenue - related parties25 5  30 
Long-term contract liabilities$2 $(2)$ $ 
(1)    No significant revenue was recognized related to past performance obligations in the current periods.
Remaining Performance Obligations
The table below includes estimated revenue expected to be recognized in the future related to performance obligations that are unsatisfied (or partially unsatisfied) as of September 30, 2024. The amounts presented below are generally limited to fixed consideration from contracts with customers that contain minimum volume commitments.
A significant portion of our future contracted revenue is excluded from the amounts presented below in accordance with ASC 606. Variable consideration that is constrained or not required to be estimated as it reflects our efforts to perform is excluded from this disclosure. Additionally, we do not disclose information on the future performance obligations for any contract with an original expected duration of one year or less, or that are terminable by our customer with little or no termination penalties. Potential future performance obligations related to renewals that have not yet been exercised or are not certain of exercise are excluded from the amounts presented below. Revenues classified as Rental income and Sales-type lease revenue are also excluded from this table.
(In billions)
2024$0.6 
20252.1 
20261.9 
20271.8 
20280.6 
2029 and thereafter0.8 
Total estimated revenue on remaining performance obligations$7.8 
As of September 30, 2024, unsatisfied performance obligations included in the Consolidated Balance Sheets are $491 million and will be recognized as revenue as the obligations are satisfied, which is generally expected to occur over the next 20 years. A portion of this amount is not disclosed in the table above as it is deemed variable consideration due to volume variability.
21

Table of Contents
15. Supplemental Cash Flow Information
 Nine Months Ended 
September 30,
(In millions)20242023
Net cash provided by operating activities included:
Interest paid (net of amounts capitalized)$724 $724 
Income taxes paid2 4 
Cash paid for amounts included in the measurement of lease liabilities:
Payments on operating leases53 53 
Net cash provided by financing activities included:
Principal payments under finance lease obligations1 1 
Non-cash investing and financing activities:
Net transfers of property, plant and equipment (to)/from materials and supplies inventory 8 
Net transfers of property, plant and equipment to lease receivable108 86 
ROU assets obtained in exchange for new operating lease obligations$34 $19 
The Consolidated Statements of Cash Flows exclude changes to the Consolidated Balance Sheets that do not affect cash. The following is a reconciliation of additions to property, plant and equipment to total capital expenditures:
 Nine Months Ended 
September 30,
(In millions)20242023
Additions to property, plant and equipment$748 $662 
(Decrease)/Increase in capital accruals(28)6 
Total capital expenditures$720 $668 
16. Commitments and Contingencies
MPLX is the subject of, or a party to, a number of pending or threatened legal actions, contingencies and commitments involving a variety of matters, including laws and regulations relating to the environment. Some of these matters are discussed below. For matters for which MPLX has not recorded a liability, MPLX is unable to estimate a range of possible loss because the issues involved have not been fully developed through pleadings, discovery or court proceedings. However, the ultimate resolution of some of these contingencies could, individually or in the aggregate, be material.
Environmental Matters
MPLX is subject to federal, state and local laws and regulations relating to the environment. These laws generally provide for control of pollutants released into the environment and require responsible parties to undertake remediation of hazardous waste disposal sites. Penalties may be imposed for non-compliance.
Accrued liabilities for remediation totaled $15 million at September 30, 2024 and $19 million December 31, 2023. It is not presently possible to estimate the ultimate amount of all remediation costs that might be incurred or the penalties, if any, that may be imposed.
MPLX is involved in environmental enforcement matters arising in the ordinary course of business. While the outcome and impact to MPLX cannot be predicted with certainty, management believes the resolution of these environmental matters will not, individually or collectively, have a material adverse effect on its consolidated results of operations, financial position or cash flows.
Other Legal Proceedings
In July 2020, Tesoro High Plains Pipeline Company, LLC (“THPP”), a subsidiary of MPLX, received a Notification of Trespass Determination from the Bureau of Indian Affairs (“BIA”) relating to a portion of the Tesoro High Plains Pipeline that crosses the Fort Berthold Reservation in North Dakota. The notification demanded the immediate cessation of pipeline operations and assessed trespass damages of approximately $187 million. After subsequent appeal proceedings and in compliance with a new order issued by the BIA, in December 2020, THPP paid approximately $4 million in assessed trespass damages and ceased use of the portion of the pipeline that crosses the property at issue. In March 2021, the BIA issued an order purporting to vacate the BIA's prior orders related to THPP’s alleged trespass and direct the Regional Director of the BIA to reconsider the issue of THPP’s alleged trespass and issue a new order. In April 2021, THPP filed a lawsuit in the District of North Dakota against the United States of America, the U.S. Department of the Interior and the BIA (collectively, the “U.S. Government Parties”) challenging the March 2021 order purporting to vacate all previous orders related to THPP’s alleged trespass. On February 8, 2022, the U.S. Government Parties filed their answer and counterclaims to THPP’s suit claiming THPP is in continued trespass with respect to the pipeline and seeking disgorgement of pipeline profits from June 1, 2013 to present, removal of the pipeline
22

Table of Contents
and remediation. On November 8, 2023, the District Court of North Dakota granted THPP’s motion to sever and stay the U.S. Government Parties’ counterclaims. The case will proceed on the merits of THPP’s challenge to the March 2021 order purporting to vacate all previous orders related to THPP’s alleged trespass. THPP continues not to operate that portion of the pipeline that crosses the property at issue.
MPLX is also a party to a number of other lawsuits and other proceedings arising in the ordinary course of business. While the ultimate outcome and impact to MPLX cannot be predicted with certainty, management believes the resolution of these other lawsuits and proceedings will not, individually or collectively, have a material adverse effect on its consolidated financial position, results of operations or cash flows.
Guarantees related to indebtedness of equity method investees
We hold a 9.19 percent indirect interest in Dakota Access, which owns and operates the Bakken Pipeline system. In 2020, the U.S. District Court for the District of Columbia (the “D.D.C.”) ordered the United States Army Corps of Engineers (“Army Corps”), which granted permits and an easement for the Bakken Pipeline system, to prepare an environmental impact statement (“EIS”) relating to an easement under Lake Oahe in North Dakota. The D.D.C. later vacated the easement. The Army Corps issued a draft EIS in September 2023 detailing various options for the easement going forward, including denying the easement, approving the easement with additional measures, rerouting the easement, or approving the easement with no changes. The Army Corps has not selected a preferred alternative, but will make a decision in its final review, after considering input from the public and other agencies. The pipeline remains operational while the Army Corps finalizes its decision which will follow the issuance of the final EIS. According to public statements from Army Corps officials, the EIS is now expected to be issued in 2025.
We have entered into a Contingent Equity Contribution Agreement whereby MPLX LP, along with the other joint venture owners in the Bakken Pipeline system, has agreed to make equity contributions to the joint venture upon certain events occurring to allow the entities that own and operate the Bakken Pipeline system to satisfy their senior note payment obligations. The senior notes were issued to repay amounts owed by the pipeline companies to fund the cost of construction of the Bakken Pipeline system.
If the vacatur of the easement results in a temporary shutdown of the pipeline, MPLX would have to contribute its 9.19 percent pro rata share of funds required to pay interest accruing on the notes and any portion of the principal that matures while the pipeline is shut down. MPLX also expects to contribute its 9.19 percent pro rata share of any costs to remediate any deficiencies to reinstate the easement and/or return the pipeline into operation. If the vacatur of the easement results in a permanent shutdown of the pipeline, MPLX would have to contribute its 9.19 percent pro rata share of the cost to redeem the bonds (including the one percent redemption premium required pursuant to the indenture governing the notes) and any accrued and unpaid interest. As of September 30, 2024, our maximum potential undiscounted payments under the Contingent Equity Contribution Agreement were approximately $78 million.
Other guarantees
MPLX’s maximum exposure to loss for WPC Parent, LLC includes an $82 million commitment to indemnify a joint venture member for our pro rata share of any payments made under a performance guarantee for construction of a pipeline by an equity method investee.
Contractual Commitments and Contingencies
From time to time and in the ordinary course of business, MPLX and its affiliates provide guarantees of MPLX’s subsidiaries payment and performance obligations in the G&P segment. Certain natural gas processing and gathering arrangements require MPLX to construct natural gas processing plants, natural gas gathering pipelines and NGL pipelines and contain certain fees and charges if specified construction milestones are not achieved for reasons other than force majeure. In certain cases, certain producers may have the right to cancel the processing arrangements if there are significant delays that are not due to force majeure. As of September 30, 2024, management does not believe there are any indications that MPLX will not be able to meet the construction milestones, that force majeure does not apply or that such fees and charges will otherwise be triggered.
23

Table of Contents
Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations
Management’s Discussion and Analysis of Financial Condition and Results of Operations should also be read in conjunction with the unaudited consolidated financial statements and accompanying footnotes included under Item 1. Financial Statements and in conjunction with our Annual Report on Form 10-K for the year ended December 31, 2023.
Disclosures Regarding Forward-Looking Statements
This Quarterly Report on Form 10-Q, particularly Management’s Discussion and Analysis of Financial Condition and Results of Operations and Quantitative and Qualitative Disclosures about Market Risk, includes forward-looking statements that are subject to risks, contingencies or uncertainties. You can identify forward-looking statements by words such as “anticipate,” “believe,” “commitment,” “could,” “design,” “estimate,” “expect,” “forecast,” “goal,” “guidance,” “intend,” “may,” “objective,” “opportunity,” “outlook,” “plan,” “policy,” “position,” “potential,” “predict,” “priority,” “project,” “prospective,” “pursue,” “seek,” “should,” “strategy,” “target,” “will,” “would” or other similar expressions that convey the uncertainty of future events or outcomes.
Forward-looking statements include, among other things, statements regarding:
future financial and operating results;
environmental, social and governance (“ESG”) plans and goals, including those related to greenhouse gas emissions and intensity, biodiversity, diversity, equity and inclusion and ESG reporting;
future levels of capital, environmental or maintenance expenditures, general and administrative and other expenses;
the success or timing of completion of ongoing or anticipated capital or maintenance projects;
business strategies, growth opportunities and expected investments, including plans to grow stable cash flows, lower costs and return capital to unitholders;
the timing and amount of future distributions or unit repurchases; and
the anticipated effects of actions of third parties such as competitors, activist investors, federal, foreign, state or local regulatory authorities, or plaintiffs in litigation.
Our forward-looking statements are not guarantees of future performance and you should not rely unduly on them, as they involve risks, uncertainties and assumptions that we cannot predict. Forward-looking and other statements regarding our ESG plans and goals are not an indication that these statements are material to investors or required to be disclosed in our filings with the SEC. In addition, historical, current, and forward-looking ESG-related statements may be based on standards for measuring progress that are still developing, internal controls and processes that continue to evolve, and assumptions that are subject to change in the future. Material differences between actual results and any future performance suggested in our forward-looking statements could result from a variety of factors, including the following:
general economic, political or regulatory developments, including inflation, interest rates, changes in governmental policies relating to refined petroleum products, crude oil, natural gas, NGLs, renewables, or taxation;
the ability of MPC to achieve its strategic objectives and the effects of those strategic decisions on us;
further impairments;
negative capital market conditions, including an increase of the current yield on common units;
the ability to achieve strategic and financial objectives, including with respect to distribution coverage, future distribution levels, proposed projects and completed transactions;
the success of MPC’s portfolio optimization, including the ability to complete any divestitures on commercially reasonable terms and/or within the expected timeframe, and the effects of any such divestitures on our business, financial condition, results of operations and cash flows;
consumer demand for refined products, natural gas, renewables and NGLs;
the adequacy of capital resources and liquidity, including the availability of sufficient cash flow to pay distributions and access to debt on commercially reasonable terms, and the ability to successfully execute business plans, growth strategies and self-funding models;
the timing and extent of changes in commodity prices and demand for crude oil, refined products, feedstocks or other hydrocarbon-based products, or renewables;
volatility in or degradation of general economic, market, industry or business conditions, including as a result of pandemics, other infectious disease outbreaks, natural hazards, extreme weather events, regional conflicts such as hostilities in the Middle East and Ukraine, inflation, or rising interest rates;
changes to the expected construction costs and timing of projects and planned investments, and the ability to obtain regulatory and other approvals with respect thereto;
the inability or failure of our joint venture partners to fund their share of operations and development activities;
the financing and distribution decisions of joint ventures we do not control;
the availability of desirable strategic alternatives to optimize portfolio assets and our ability to obtain regulatory and other approvals with respect thereto;
completion of midstream infrastructure by competitors;
24

Table of Contents
disruptions due to equipment interruption or failure, including electrical shortages and power grid failures;
the suspension, reduction or termination of MPC’s obligations under MPLX’s commercial agreements;
modifications to financial policies, capital budgets, and earnings and distributions;
the ability to manage disruptions in credit markets or changes to credit ratings;
our ability to comply with federal and state environmental, economic, health and safety, energy and other policies and regulations or enforcement actions initiated thereunder;
adverse results in litigation;
the effect of restructuring or reorganization of business components;
the potential effects of changes in tariff rates on our business, financial condition, results of operations and cash flows;
foreign imports and exports of crude oil, refined products, natural gas and NGLs;
changes in producer customers’ drilling plans or in volumes of throughput of crude oil, natural gas, NGLs, refined products, other hydrocarbon-based products, or renewables;
changes in the cost or availability of third-party vessels, pipelines, railcars and other means of transportation for crude oil, natural gas, NGLs, feedstocks, refined products, or renewables;
the price, availability and acceptance of alternative fuels and alternative-fuel vehicles and laws mandating such fuels or vehicles;
actions taken by our competitors, including pricing adjustments and the expansion and retirement of pipeline capacity, processing, fractionation and treating facilities in response to market conditions;
expectations regarding joint venture arrangements and other acquisitions or divestitures of assets;
midstream and refining industry overcapacity or undercapacity;
industrial incidents or other unscheduled shutdowns affecting our machinery, pipelines, processing, fractionation and treating facilities or equipment, means of transportation, or those of our suppliers or customers;
acts of war, terrorism or civil unrest that could impair our ability to gather, process, fractionate or transport crude oil, natural gas, NGLs, refined products, or renewables;
labor and material shortages;
the timing and ability to obtain necessary regulatory approvals and permits and to satisfy other conditions necessary to complete planned projects or to consummate planned transactions within the expected timeframe, if at all;
the availability of desirable strategic alternatives to optimize portfolio assets and the ability to obtain regulatory and other approvals with respect thereto;
political pressure and influence of environmental groups and other stakeholders that are adverse to the production, gathering, refining, processing, fractionation, transportation and marketing of crude oil or other feedstocks, refined products, natural gas, NGLs, other hydrocarbon-based products, or renewables;
the imposition of windfall profit taxes, maximum margin penalties or minimum inventory requirements on companies operating in the energy industry in California or other jurisdictions; and
our ability to successfully implement our sustainable energy strategy and principles and achieve our ESG goals and targets within the expected timeframe, if at all.
For additional risk factors affecting our business, see the risk factors described in our Annual Report on Form 10-K for the year ended December 31, 2023. We undertake no obligation to update any forward-looking statements except to the extent required by applicable law.
MPLX Overview
We are a diversified, large-cap master limited partnership formed by MPC in 2012 that owns and operates midstream energy infrastructure and logistics assets, and provides fuels distribution services. The business consists of two segments based on the nature of services it offers: Logistics and Storage (“L&S”) and Gathering and Processing (“G&P”).
Our L&S segment gathers, transports, stores and distributes crude oil, refined products, including renewable diesel, and other hydrocarbon-based products. Additionally, the segment markets refined products. The profitability of pipeline transportation operations primarily depends on tariff rates and the volumes shipped through the pipelines. The profitability of marine operations primarily depends on the quantity and availability of our vessels and barges. The profitability of our terminal operations primarily depends on the throughput volumes at our terminals. The profitability of our fuels distribution services primarily depends on the sales volumes of certain refined products. The profitability of our refining logistics operations depends on the quantity and availability of our refining logistics assets. A majority of the crude oil and refined product shipments on our pipelines and marine vessels, the throughput at our terminals and refining logistics assets serve MPC and our fuels distribution services are used solely by MPC. We have various long-term, fee-based commercial agreements related to services provided to MPC. Under these agreements, we receive various commitments of minimum throughput, storage and distribution volumes as well as commitments to pay for all available capacity of certain assets. The volume of crude oil that we transport is directly affected by the supply of, and refiner demand for, crude oil in the markets served directly by our crude oil pipelines, terminals and marine operations. Key factors in this supply and demand balance are the production levels of crude oil by producers in various regions or fields, the
25

Table of Contents
availability and cost of alternative modes of transportation, the volumes of crude oil processed at refineries and refinery and transportation system maintenance levels. The volume of refined products that we transport, store, distribute and market is directly affected by the production levels of, and user demand for, refined products in the markets served by our refined product pipelines and marine operations. In most of our markets, demand for gasoline and distillate peaks during the summer driving season, which extends from May through September of each year, and declines during the fall and winter months. As with crude oil, other transportation alternatives and system maintenance levels influence refined product movements.
Our G&P segment gathers, processes and transports natural gas and transports, fractionates, stores and markets NGLs. NGL and natural gas prices are volatile and are impacted by changes in fundamental supply and demand, as well as market uncertainty, availability of NGL transportation and fractionation capacity and a variety of additional factors that are beyond our control. G&P segment profitability is affected by prevailing commodity prices primarily as a result of processing at our own or third‑party processing plants, purchasing and selling or gathering and transporting volumes of natural gas at index‑related prices and the cost of third‑party transportation and fractionation services. To the extent that commodity prices influence the level of natural gas drilling by our producer customers, such prices also affect profitability.
Significant Financial and Other Highlights
Significant financial highlights for the three months ended September 30, 2024 and September 30, 2023 are shown in the chart below. Refer to the Non-GAAP Financial Information, the Results of Operations and the Liquidity and Capital Resources sections for further information.
12663
(1)     Non-GAAP measure. See reconciliations that follow for the most directly comparable GAAP measures.
Other Highlights
Returned $949 million and $2,849 million of capital to unitholders in the three and nine months ended September 30, 2024, via distributions and unit repurchases.
Announced a third quarter 2024 distribution of $0.9565 per common unit, representing a 12.5% increase over the prior quarter’s distribution.
Acquired an additional 20 percent interest in the BANGL natural gas liquids pipeline, bringing our interest in the pipeline to 45 percent.
Our 200 MMcf/d Preakness II processing plant began operations in July.
Executing our growth strategy in the Northeast with the addition of Harmon Creek III, a 300 MMcf/d processing plant and 40 mbpd de-ethanizer; expected to bring total Northeast processing and fractionation capacity to 8.1 billion cubic feet per day and 800 mbpd, respectively, in the second half of 2026.
Non-GAAP Financial Information
Our management uses a variety of financial and operating metrics to analyze our performance. These metrics are significant factors in assessing our operating results and profitability and include the non-GAAP financial measures of Adjusted EBITDA, DCF, adjusted free cash flow (“Adjusted FCF”), and Adjusted FCF after distributions.
26

Table of Contents
Adjusted EBITDA is a financial performance measure used by management, industry analysts, investors, lenders, and rating agencies to assess the financial performance and operating results of our ongoing business operations. Additionally, we believe adjusted EBITDA provides useful information to investors for trending, analyzing and benchmarking our operating results from period to period as compared to other companies that may have different financing and capital structures. We define Adjusted EBITDA as net income adjusted for: (i) provision for income taxes; (ii) net interest and other financial costs; (iii) depreciation and amortization; (iv) income/(loss) from equity method investments; (v) distributions and adjustments related to equity method investments; (vi) impairment expense; (vii) noncontrolling interests; and (viii) other adjustments, as applicable.
DCF is a financial performance and liquidity measure used by management and by the board of directors of our general partner as a key component in the determination of cash distributions paid to unitholders. We believe DCF is an important financial measure for unitholders as an indicator of cash return on investment and to evaluate whether the partnership is generating sufficient cash flow to support quarterly distributions. In addition, DCF is commonly used by the investment community because the market value of publicly traded partnerships is based, in part, on DCF and cash distributions paid to unitholders. We define DCF as Adjusted EBITDA adjusted for: (i) deferred revenue impacts; (ii) sales-type lease payments, net of income; (iii) adjusted net interest and other financial costs; (iv) net maintenance capital expenditures; (v) equity method investment capital expenditures paid out; and (vi) other adjustments as deemed necessary.
Adjusted FCF and Adjusted FCF after distributions are financial liquidity measures used by management in the allocation of capital and to assess financial performance. We believe that unitholders may use this metric to analyze our ability to manage leverage and return capital. We define Adjusted FCF as net cash provided by operating activities adjusted for: (i) net cash used in investing activities; (ii) cash contributions from MPC; and (iii) cash distributions to noncontrolling interests. We define Adjusted FCF after distributions as Adjusted FCF less base distributions to common and preferred unitholders.
We believe that the presentation of Adjusted EBITDA, DCF, Adjusted FCF and Adjusted FCF after distributions provides useful information to investors in assessing our financial condition and results of operations. The GAAP measures most directly comparable to Adjusted EBITDA and DCF are net income and net cash provided by operating activities while the GAAP measure most directly comparable to Adjusted FCF and Adjusted FCF after distributions is net cash provided by operating activities. These non-GAAP financial measures should not be considered alternatives to net income or net cash provided by operating activities as they have important limitations as analytical tools because they exclude some but not all items that affect net income and net cash provided by operating activities or any other measure of financial performance or liquidity presented in accordance with GAAP. These non-GAAP financial measures should not be considered in isolation or as substitutes for analysis of our results as reported under GAAP. Additionally, because non-GAAP financial measures may be defined differently by other companies in our industry, our definitions may not be comparable to similarly titled measures of other companies, thereby diminishing their utility. For a reconciliation of Adjusted EBITDA and DCF to their most directly comparable measures calculated and presented in accordance with GAAP, see Results of Operations. For a reconciliation of Adjusted FCF and Adjusted FCF after distributions to their most directly comparable measure calculated and presented in accordance with GAAP, see Liquidity and Capital Resources.
27

Table of Contents
Results of Operations
The following tables and discussion summarize our results of operations, including a reconciliation of Adjusted EBITDA and DCF from Net income and Net cash provided by operating activities, the most directly comparable GAAP financial measures. This discussion should be read in conjunction with Item 1. Financial Statements and is intended to provide investors with a reasonable basis for assessing our historical operations, but should not serve as the only criteria for predicting our future performance.
 Three Months Ended September 30,Nine Months Ended September 30,
(In millions)20242023Variance20242023Variance
Revenues and other income:
Total revenues and other income$2,972 $2,912 $60 $8,870 $8,315 $555 
Costs and expenses:
Cost of revenues (excludes items below)404 367 37 1,159 1,023 136 
Purchased product costs403 474 (71)1,148 1,234 (86)
Rental cost of sales22 20 61 60 
Rental cost of sales - related parties(3)14 24 (10)
Purchases - related parties402 442 (40)1,162 1,160 
Depreciation and amortization322 301 21 959 907 52 
General and administrative expenses107 102 323 280 43 
Other taxes32 44 (12)99 102 (3)
Total costs and expenses1,697 1,758 (61)4,925 4,790 135 
Income from operations1,275 1,154 121 3,945 3,525 420 
Net interest and other financial costs226 225 692 701 (9)
Income before income taxes1,049 929 120 3,253 2,824 429 
Provision for income taxes
Net income1,047 928 119 3,248 2,822 426 
Less: Net income attributable to noncontrolling interests10 10 — 30 28 
Net income attributable to MPLX LP1,037 918 119 3,218 2,794 424 
Adjusted EBITDA attributable to MPLX LP(1)
1,714 1,596 118 5,002 4,646 356 
DCF attributable to MPLX(1)
$1,446 $1,373 $73 $4,220 $3,956 $264 
(1)     Non-GAAP measure. See reconciliation below to the most directly comparable GAAP measures.
28

Table of Contents

 Three Months Ended September 30,Nine Months Ended September 30,
(In millions)20242023Variance20242023Variance
Reconciliation of Adjusted EBITDA attributable to MPLX LP and DCF attributable to LP unitholders from Net income:
Net income$1,047 $928 $119 $3,248 $2,822 $426 
Provision for income taxes
Net interest and other financial costs226 225 692 701 (9)
Income from operations1,275 1,154 121 3,945 3,525 420 
Depreciation and amortization322 301 21 959 907 52 
Income from equity method investments(149)(159)10 (631)(438)(193)
Distributions/adjustments related to equity method investments253 208 45 671 551 120 
Garyville incident response costs(1)
— 63 (63)— 63 (63)
Other(2)
24 40 (16)91 69 22 
Adjusted EBITDA1,725 1,607 118 5,035 4,677 358 
Adjusted EBITDA attributable to noncontrolling interests(11)(11)— (33)(31)(2)
Adjusted EBITDA attributable to MPLX LP1,714 1,596 118 5,002 4,646 356 
Deferred revenue impacts(15)25 (40)65 (59)
Sales-type lease payments, net of income20 11 
Adjusted net interest and other financial costs(3)
(212)(212)— (651)(650)(1)
Maintenance capital expenditures, net of reimbursements(40)(28)(12)(120)(93)(27)
Equity method investment maintenance capital expenditures paid out(4)(4)— (11)(11)— 
Other(4)(7)(26)(10)(16)
DCF attributable to MPLX LP1,446 1,373 73 4,220 3,956 264 
Preferred unit distributions(6)(25)19 (21)(76)55 
DCF attributable to LP unitholders$1,440 $1,348 $92 $4,199 $3,880 $319 
(1)    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 (“Garyville Incident”). We incurred $63 million of incident response costs during the three and nine months ended September 30, 2023.
(2)    Includes unrealized derivative gain/(loss), equity-based compensation and other miscellaneous items.
(3)    Represents Net interest and other financial costs excluding gain/loss on extinguishment of debt and amortization of deferred financing costs.

29

Table of Contents
 Three Months Ended September 30,Nine Months Ended September 30,
(In millions)20242023Variance20242023Variance
Reconciliation of Adjusted EBITDA attributable to MPLX LP and DCF attributable to LP unitholders from Net cash provided by operating activities:
Net cash provided by operating activities$1,415 $1,244 $171 $4,271 $3,908 $363 
Changes in working capital items40 47 (7)(55)(76)21 
All other, net(3)— (3)(13)(21)
Loss on extinguishment of debt— — — — (9)
Adjusted net interest and other financial costs(1)
212 212 — 651 650 
Other adjustments to equity method investment distributions34 13 21 75 25 50 
Garyville incident response costs(2)
— 63 (63)— 63 (63)
Other27 28 (1)106 90 16 
Adjusted EBITDA1,725 1,607 118 5,035 4,677 358 
Adjusted EBITDA attributable to noncontrolling interests(11)(11)— (33)(31)(2)
Adjusted EBITDA attributable to MPLX LP1,714 1,596 118 5,002 4,646 356 
Deferred revenue impacts(15)25 (40)65 (59)
Sales-type lease payments, net of income20 11 
Adjusted net interest and other financial costs(1)
(212)(212)— (651)(650)(1)
Maintenance capital expenditures, net of reimbursements(40)(28)(12)(120)(93)(27)
Equity method investment maintenance capital expenditures paid out(4)(4)— (11)(11)— 
Other(4)(7)(26)(10)(16)
DCF attributable to MPLX LP1,446 1,373 73 4,220 3,956 264 
Preferred unit distributions(6)(25)19 (21)(76)55 
DCF attributable to LP unitholders$1,440 $1,348 $92 $4,199 $3,880 $319 
(1)    Represents Net interest and other financial costs excluding gain/loss on extinguishment of debt and amortization of deferred financing costs.
(2)    We incurred $63 million of Garyville Incident response costs during the three and nine months ended September 30, 2023.
Three months ended September 30, 2024 compared to three months ended September 30, 2023
Total revenues and other income increased $60 million in the third quarter of 2024 compared to the same period of 2023. The increase was driven by higher pipeline tariff rates and other fee escalations, as well as incremental revenues from the consolidation of MarkWest Torñado GP, L.L.C. (“Torñado”) in December 2023 (the “Torñado Acquisition”) and the acquisition of additional ownership interest in existing joint ventures and gathering assets in the Utica basin (the “Utica Midstream Acquisition”) that was completed in the first quarter of 2024. The increases were partially offset with a $33 million decrease in product related revenue as a result of lower NGL prices and sales volumes within the G&P segment.
Cost of revenues increased $37 million in the third quarter of 2024 compared to the same period of 2023. The increase is primarily due to higher volumes and is attributable to costs that are largely offset in revenues. The third quarter of 2024 also includes an increase of $9 million as a result of the consolidation of Torñado in December 2023 as well as higher project-related spending.
Purchased product costs decreased $71 million in the third quarter of 2024 compared to the same period of 2023. This was primarily due to lower NGL volumes of $40 million, lower NGL prices of $24 million and a $7 million decrease in the fair value of an embedded derivative in a natural gas purchase commitment.
Purchases - related parties decreased $40 million in the third quarter of 2024 compared to the same period of 2023. The decrease was driven by $63 million of Garyville Incident response costs recognized in the third quarter of 2023. The decrease was partially offset by changes in presentation driven by modification of an agreement with MPC in the first quarter of 2024 and higher employee costs from MPC.
Depreciation and amortization increased $21 million in the third quarter of 2024 compared to the same period of 2023. This was primarily due to incremental depreciation associated with assets acquired in conjunction with the Torñado Acquisition in December 2023 and the Utica Midstream Acquisition in the first quarter of 2024, as well as other assets placed in service
30

Table of Contents
subsequent to the third quarter of 2023.
Nine months ended September 30, 2024 compared to nine months ended September 30, 2023
Total revenues and other income increased $555 million in the first nine months of 2024 compared to the same period of 2023. This was primarily due to higher pipeline tariff rates within in the L&S segment, higher volumes and throughput fee rates within the G&P segment, and incremental revenues from the consolidation of Torñado in December 2023 and the Utica Midstream Acquisition that was completed in the first quarter of 2024. The increase also includes a $151 million gain related to the strategic transaction combining the Whistler and Rio Bravo natural gas assets that was completed in the second quarter of 2024 (the “Whistler Joint Venture Transaction”), a $25 million benefit from business interruption insurance proceeds and a $20 million gain related to an equity method investment acquisition in the first quarter of 2024. Income from equity method investments also benefited from increased throughput on equity method investment pipeline systems in the 2024 period.
Cost of revenues increased $136 million in the first nine months of 2024 compared to the same period of 2023. The increase is primarily due to higher volumes and is attributable to costs that are largely offset in revenues. The increase also includes $33 million as a result of the consolidation of Torñado in December 2023 as well as higher project-related spending.
Purchased product costs decreased $86 million in the first nine months of 2024 compared to the same period of 2023. This was primarily due to lower NGL volumes of $87 million and lower NGL prices of $8 million, partially offset by a change of $9 million due to changes in the fair value of an embedded derivative in a natural gas purchase commitment.
Purchases - related parties increased $2 million in the first nine months of 2024 compared to the same period of 2023. Higher costs in the first nine months of 2024 related to changes in presentation driven by the modification of an agreement with MPC in the first quarter of 2024 and higher costs from MPC, including employee costs, were largely offset by a decrease related to $63 million of Garyville Incident response costs recognized in the 2023 period.
Depreciation and amortization increased $52 million in the first nine months of 2024 compared to the same period of 2023. This was primarily due to incremental depreciation associated with assets acquired in conjunction with the Torñado Acquisition in December 2023 and the Utica Midstream Acquisition in the first quarter of 2024, as well as other assets placed in service subsequent to the third quarter of 2023.
General and administrative expenses increased $43 million in the first nine months of 2024 compared to the same period of 2023, due to increased contractor service costs and higher employee costs from MPC.
Segment Results
We classify our business in the following reportable segments: L&S and G&P. We evaluate the performance of our segments using Segment Adjusted EBITDA. Segment Adjusted EBITDA represents Adjusted EBITDA attributable to the reportable segments. Amounts included in net income and excluded from Segment Adjusted EBITDA include: (i) depreciation and amortization; (ii) net interest and other financial costs; (iii) income/(loss) from equity method investments; (iv) distributions and adjustments related to equity method investments; (v) impairment expense; (vi) noncontrolling interests; and (vii) 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.
The tables below present information about Segment Adjusted EBITDA for the reported segments for the three and nine months ended September 30, 2024 and September 30, 2023.
31

Table of Contents
L&S Segment
Third Quarter L&S Segment Financial Highlights (in millions)
7879
Three Months Ended September 30,Nine Months Ended September 30,
(In millions)20242023Variance20242023Variance
Service revenue$1,158 $1,130 $28 $3,367 $3,223 $144 
Rental income223 216 666 638 28 
Product related revenue(1)14 14 — 
Sales-type lease revenue118 129 (11)359 379 (20)
Income from equity method investments80 95 (15)429 248 181 
Other income33 15 18 113 47 66 
Total segment revenues and other income1,617 1,591 26 4,948 4,549 399 
Cost of revenues167 158 466 451 15 
Purchases - related parties291 341 (50)840 848 (8)
Depreciation and amortization132 130 393 399 (6)
General and administrative expenses62 60 189 160 29 
Other taxes22 32 (10)62 71 (9)
Total costs and expenses674 721 (47)1,950 1,929 21 
Segment Adjusted EBITDA1,157 1,091 66 3,384 3,139 245 
Capital expenditures112 73 39 299 251 48 
Investments in unconsolidated affiliates(1)
$10 $$$103 $23 $80 
(1)    The nine months ended September 30, 2024 includes a contribution of $92 million to a joint venture (“Dakota Access”) that owns and operates the Dakota Access Pipeline and Energy Transfer Crude Oil Pipeline projects to fund our share of a debt repayment by the joint venture.
Three months ended September 30, 2024 compared to three months ended September 30, 2023
Service revenue increased $28 million in the third quarter of 2024 compared to the same period of 2023. This was primarily driven by $18 million of higher pipeline tariff rates and other fee escalations, in addition to changes in presentation driven by agreement modifications.
Sales-type lease revenue decreased $11 million in the third quarter of 2024 compared to the same period of 2023. This was primarily due to changes in the presentation of lease income between service revenue, rental income and sales-type lease revenue due to modifications of lease contracts.
Income from equity method investments decreased $15 million in the third quarter of 2024 compared to the same period of 2023. This was primarily driven by financing costs incurred at the joint venture level. See Supplemental Information on Equity Method Investments for additional information regarding the results of our equity method investments.
Other income increased $18 million in the third quarter of 2024 compared to the same period of 2023. This was primarily due to changes in presentation driven by modification of an agreement with MPC in the first quarter of 2024.
Purchases - related parties decreased $50 million in the third quarter of 2024 compared to the same period of 2023, primarily due to Garyville Incident response costs of $63 million recognized in the third quarter of 2023, partially offset by changes in presentation driven by modification of an agreement with MPC in the first quarter of 2024 and higher employee costs from MPC.
32

Table of Contents
Nine months ended September 30, 2024 compared to nine months ended September 30, 2023
Service revenue increased $144 million in the first nine months of 2024 compared to the same period of 2023. This was primarily driven by $150 million of higher pipeline tariff rates and other fee escalations, changes in presentation driven by agreement modifications and additional marine equipment, partially offset by $12 million due to lower throughput.
Rental income increased $28 million in the first nine months of 2024 compared to the same period of 2023. This was primarily due to $29 million of fee escalations related to our refining logistics assets, partially offset by changes in presentation driven by agreement modifications.
Sales-type lease revenue decreased $20 million in the first nine months of 2024 compared to the same period of 2023. This was primarily due to changes in the presentation of lease income between service revenue, rental income and sales-type lease revenue due to modifications of lease contracts.
Income from equity methods investments increased $181 million in the first nine months of 2024 compared to the same period of 2023. This was primarily driven by a $151 million gain related to the dilution of our ownership interest in connection with the Whistler Joint Venture Transaction, as well as increased throughput on equity method investment pipeline systems. These increases were partially offset by higher financing costs incurred at the joint venture level. See Supplemental Information on Equity Method Investments for additional information regarding the results of our equity method investments.
Other income increased $66 million in the first nine months of 2024 compared to the same period of 2023. This was primarily due to changes in presentation driven by modification of an agreement with MPC in the first quarter of 2024 and business interruption insurance proceeds.
Cost of revenues increased $15 million in the first nine months of 2024 compared to the same period of 2023. This is primarily due to higher project-related spending. The increase was partially offset by changes in presentation driven by agreement modifications of $10 million.
Purchases - related parties decreased $8 million in the first nine months of 2024 compared to the same period of 2023, primarily due to Garyville Incident response costs of $63 million recognized in the 2023 period, partially offset by changes in presentation driven by agreement modifications and $15 million of higher employee costs from MPC.
General and administrative expenses increased $29 million in the first nine months of 2024 compared to the same period of 2023, primarily due to increased contractor service costs and higher employee costs, including those from MPC.
33

Table of Contents
L&S Operating Data
23
Three Months Ended 
September 30,
Nine Months Ended 
September 30,
2024202320242023
L&S
Pipeline throughput (mbpd)
Crude oil pipelines3,895 3,911 3,769 3,796 
Product pipelines2,056 1,975 1,987 2,027 
Total pipelines5,951 5,886 5,756 5,823 
Average tariff rates ($ per barrel)(1)
Crude oil pipelines$1.01 $0.99 $1.01 $0.95 
Product pipelines1.01 0.99 0.99 0.88 
Total pipelines$1.01 $0.99 $1.00 $0.93 
Terminal throughput (mbpd)3,268 3,228 3,132 3,167 
Marine Assets (number in operation)(2)
Barges311 305 311 305 
Towboats28 27 28 27 
(1)     Average tariff rates calculated using pipeline transportation revenues divided by pipeline throughput barrels. Transportation revenues include tariff and other fees, which may vary by region and nature of services provided.
(2)     Represents total at end of period.
34

Table of Contents
G&P Segment
Third Quarter G&P Segment Financial Highlights (in millions)
78 80
Three Months Ended September 30,Nine Months Ended September 30,
(In millions)20242023Variance20242023Variance
Service revenue$617 $549 $68 $1,785 $1,620 $165 
Rental income56 52 165 155 10 
Product related revenue565 598 (33)1,606 1,629 (23)
Sales-type lease revenue 34 34 — 102 101 
Income from equity method investments69 64 202 190 12 
Other income14 24 (10)62 71 (9)
Total segment revenues and other income1,355 1,321 34 3,922 3,766 156 
Cost of revenues264 237 27 768 656 112 
Purchased product costs403 474 (71)1,148 1,234 (86)
Purchases - related parties111 101 10 322 312 10 
Depreciation and amortization190 171 19 566 508 58 
General and administrative expenses45 42 134 120 14 
Other taxes10 12 (2)37 31 
Total costs and expenses1,023 1,037 (14)2,975 2,861 114 
Segment Adjusted EBITDA557 505 52 1,618 1,507 111 
Capital expenditures189 151 38 421 417 
Investments in unconsolidated affiliates$22 $$16 $83 $67 $16 
Three months ended September 30, 2024 compared to three months ended September 30, 2023
Service revenue increased $68 million in the third quarter of 2024 compared to the same period of 2023. This was primarily due to $39 million of incremental revenues from the consolidation of Torñado in December 2023 and an increase of $15 million from the Utica Midstream Acquisition that was completed in the first quarter of 2024, as well as higher volumes and higher throughput fee rates across the Marcellus, Rockies and Bakken of $21 million. The increases were partially offset by lower volumes in the STACK Shale basin in the Southwest.
Product related revenue decreased $33 million in the third quarter of 2024 compared to the same period of 2023. This was primarily due to lower NGL prices in the Southwest of $31 million and lower NGL sales volumes in the Southwest of $20 million, partially offset by changes in the fair value of our propane contracts of $11 million and higher NGL sales volumes in the Rockies of $7 million.
Cost of revenues increased $27 million in the third quarter of 2024 compared to the same period of 2023. This increase is primarily due to higher volumes across all regions and is attributable to costs that are largely offset in Service revenue and Product related revenue. Cost of revenues also increased $9 million as a result of the consolidation of Torñado in December 2023 and increased $5 million from the Utica Midstream acquisition that was completed in the first quarter of 2024.
Purchased product costs decreased $71 million in the third quarter of 2024 compared to the same period of 2023. This was primarily due to lower NGL volumes in the Southwest of $40 million, lower NGL prices in the Southwest of $24 million and a $7 million decrease in the fair value of an embedded derivative in a natural gas purchase commitment.
Purchases - related parties increased $10 million in the third quarter of 2024 compared to the same period of 2023. The increase includes higher transportation costs in the Southwest and increased employee costs from MPC.
35

Table of Contents
Depreciation and amortization increased $19 million in the third quarter of 2024 compared to the same period of 2023. This was primarily due to incremental depreciation associated with assets acquired in the Torñado Acquisition in December 2023 and the Utica Midstream Acquisition in the first quarter of 2024, as well as other assets placed in service subsequent to the third quarter of 2023.
Nine months ended September 30, 2024 compared to nine months ended September 30, 2023
Service revenue increased $165 million in the first nine months of 2024 compared to the same period of 2023. This was primarily due to $93 million of incremental revenues from the consolidation of Torñado in December 2023, an increase of $30 million from the Utica Midstream Acquisition that was completed in the first quarter of 2024, as well as higher volumes and higher throughput fee rates across the Marcellus, Rockies and Bakken of $78 million. The increases were partially offset by lower volumes in the STACK Shale basin in the Southwest.
Product related revenue decreased $23 million in the first nine months of 2024 compared to the same period of 2023. This was primarily due to lower NGL sales volumes in the Southwest of $51 million and lower NGL prices in the Southwest and Rockies of $33 million, partially offset by higher NGL volumes in the Rockies and Bakken of $63 million.
Income from equity method investments increased $12 million in the first nine months of 2024 compared to the same period of 2023. This was primarily due to higher volumes and higher throughput fee rates in the Utica and Marcellus of $22 million in addition to incremental income from the Utica Midstream Acquisition that was completed in the first quarter of 2024, partially offset by a $26 million decrease from the consolidation of Torñado in December 2023. See Supplemental Information on Equity Method Investments for additional information regarding the results of our equity method investments.
Cost of revenues increased $112 million in the first nine months of 2024 compared to the same period of 2023. This increase is primarily due to higher volumes in the Rockies, Bakken and Marcellus and is attributable to costs that are largely offset in Service revenue and Product related revenue. Cost of revenues also increased $33 million as a result of the consolidation of Torñado in December 2023 and increased $8 million from the Utica Midstream Acquisition that was completed in the first quarter of 2024.
Purchased product costs decreased $86 million in the first nine months of 2024 compared to the same period of 2023. This was primarily due to lower NGL volumes in the Southwest of $87 million and lower NGL prices in the Southwest of $8 million, partially offset by an increase of $9 million due to changes in the fair value of an embedded derivative in a natural gas purchase commitment.
Purchases - related parties increased $10 million in the first nine months of 2024 compared to the same period of 2023. This was primarily due to increased employee costs from MPC and higher transportation costs in the Southwest.
Depreciation and amortization increased $58 million in the first nine months of 2024 compared to the same period of 2023. This was primarily due to incremental depreciation associated with assets acquired in conjunction with the Torñado Acquisition in December 2023 and the Utica Midstream Acquisition in the first quarter of 2024, as well as other assets placed in service subsequent to the third quarter of 2023.
36

Table of Contents
G&P Operating Data
232425
(1)     Other includes Southern Appalachia, Bakken and Rockies Operations.
MPLX LP(1)
MPLX LP Operated(2)
Three Months Ended 
September 30,
Three Months Ended 
September 30,
2024202320242023
G&P
Gathering Throughput (MMcf/d)
Marcellus Operations1,527 1,376 1,527 1,376 
Utica Operations354 — 2,616 2,375 
Southwest Operations1,813 1,302 1,813 1,742 
Bakken Operations181 160 181 160 
Rockies Operations542 490 600 604 
Total gathering throughput4,417 3,328 6,737 6,257 
Natural Gas Processed (MMcf/d)
Marcellus Operations4,393 4,187 6,013 5,803 
Utica Operations— — 794 557 
Southwest Operations1,977 1,405 1,977 1,744 
Southern Appalachia Operations215 207 215 207 
Bakken Operations179 159 179 159 
Rockies Operations597 491 597 491 
Total natural gas processed7,361 6,449 9,775 8,961 
C2 + NGLs Fractionated (mbpd)
Marcellus Operations(3)
550 546 550 546 
Utica Operations(3)
— — 48 34 
Southern Appalachia Operations12 10 12 10 
Bakken Operations20 20 20 20 
Rockies Operations
Total C2 + NGLs fractionated(4)
587 579 635 613 

37

Table of Contents
MPLX LP(1)
MPLX LP Operated(2)
Nine Months Ended 
September 30
Nine Months Ended 
September 30
2024202320242023
G&P
Gathering Throughput (MMcf/d)
Marcellus Operations1,515 1,353 1,515 1,353 
Utica Operations239 — 2,522 2,387 
Southwest Operations1,668 1,345 1,668 1,775 
Bakken Operations183 159 183 159 
Rockies Operations563 463 639 584 
Total gathering throughput4,168 3,320 6,527 6,258 
Natural Gas Processed (MMcf/d)
Marcellus Operations4,360 4,107 5,963 5,683 
Utica Operations— — 801 533 
Southwest Operations1,786 1,442 1,786 1,771 
Southern Appalachian Operations218 219 218 219 
Bakken Operations182 157 182 157 
Rockies Operations622 472 622 472 
Total natural gas processed7,168 6,397 9,572 8,835 
C2 + NGLs Fractionated (mbpd)
Marcellus Operations(3)
558 533 558 533 
Utica Operations(3)
— — 49 31 
Southern Appalachian Operations12 10 12 10 
Bakken Operations20 19 20 19 
Rockies Operations
Total C2 + NGLs fractionated(4)
595 565 644 596 
(1)    This column represents operating data for entities that have been consolidated into the MPLX financial statements.
(2)    This column represents operating data for entities that have been consolidated into the MPLX financial statements as well as operating data for MPLX-operated equity method investments.
(3)    Entities within the Marcellus and Utica Operations jointly own the Hopedale fractionation complex. Hopedale throughput is included in the Marcellus and Utica Operations and represents each region’s utilization of the complex.
(4)    Purity ethane makes up approximately 246 mbpd of MPLX LP consolidated total fractionated products for both of the three months ended September 30, 2024 and September 30, 2023, and approximately 258 mbpd and 240 mbpd of total fractionated products for the nine months ended September 30, 2024 and September 30, 2023, respectively. Purity ethane makes up approximately 262 mbpd and 254 mbpd of MPLX LP Operated total fractionated products for the three months ended September 30, 2024 and September 30, 2023, respectively, and approximately 273 mbpd and 246 mbpd of total fractionated products for the nine months ended September 30, 2024 and September 30, 2023, respectively.
Three Months Ended 
September 30,
Nine Months Ended 
September 30,
2024202320242023
Pricing Information
Natural Gas NYMEX HH ($ per MMBtu)$2.23 $2.66 $2.22 $2.58 
C2 + NGL Pricing ($ per gallon)(1)
$0.67 $0.68 $0.70 $0.69 
(1)    C2 + NGL pricing based on Mont Belvieu prices assuming an NGL barrel of approximately 35 percent ethane, 35 percent propane, six percent Iso-Butane, 12 percent normal butane and 12 percent natural gasoline.
38

Table of Contents
Supplemental Information on Equity Method Investments
The following table presents MPLX’s income (loss) from equity method investments for the three and nine months ended September 30, 2024 and September 30, 2023:
Three Months Ended 
September 30,
Nine Months Ended 
September 30,
(In millions)2024202320242023
Income (loss) from equity method investments:
L&S
BANGL, LLC$(3)$(1)$$— 
Illinois Extension Pipeline Company, L.L.C.15 10 44 35 
LOOP LLC13 
MarEn Bakken Company LLC23 22 76 63 
WPC Parent, LLC(1)
16 26 218 57 
Other26 33 80 80 
Total L&S80 95 429 248 
G&P
MarkWest EMG Jefferson Dry Gas Gathering Company, L.L.C.17 16 53 51 
MarkWest Utica EMG, L.L.C.19 17 57 39 
Ohio Gathering Company L.L.C.— — 
Sherwood Midstream LLC27 27 81 77 
Other23 
Total G&P69 64 202 190 
Total$149 $159 $631 $438 
(1)    In May 2024, MPLX completed the Whistler Joint Venture Transaction, which resulted in the formation of a new entity, WPC Parent, LLC. Results include the equity method investment income of our interest in Whistler Pipeline, LLC, prior to the transaction date, and results of the equity method investment income of our ownership in WPC Parent, LLC, subsequent to the transaction date. The nine months ended September 30, 2024 include a gain of $151 million related to the dilution of our ownership interest in connection with the Whistler Joint Venture Transaction.

The following table presents the impact of equity method investment distributions and other adjustments included in MPLX’s EBITDA for the three and nine months ended September 30, 2024 and September 30, 2023:
Three Months Ended 
September 30,
Nine Months Ended 
September 30,
(In millions)2024202320242023
Distributions/adjustments related to equity method investments:
L&S
BANGL, LLC$$— $$— 
Illinois Extension Pipeline Company, L.L.C.18 13 41 34 
LOOP LLC— 14 
MarEn Bakken Company LLC27 29 87 86 
WPC Parent, LLC(1)
56 36 123 68 
Other37 35 110 86 
Total L&S150 113 382 278 
G&P
MarkWest EMG Jefferson Dry Gas Gathering Company, L.L.C.22 20 62 67 
MarkWest Utica EMG, L.L.C.32 27 90 62 
Ohio Gathering Company L.L.C.13 — 24 — 
Sherwood Midstream LLC28 28 90 83 
Other20 23 61 
Total G&P103 95 289 273 
Total$253 $208 $671 $551 
(1)    In May 2024, MPLX completed the Whistler Joint Venture Transaction, which resulted in the formation of a new entity, WPC Parent, LLC. Results include the equity method investment distributions and adjustments of our interest in Whistler Pipeline, LLC, prior to the transaction date, and results of the equity method investment distributions and adjustments of our ownership in WPC Parent, LLC, subsequent to the transaction date.
39

Table of Contents
Seasonality
The volume of crude oil and refined products transported and stored utilizing our assets is affected by the level of supply and demand for crude oil and refined products in the markets served directly or indirectly by our assets. The majority of effects of seasonality on the L&S segment’s revenues are mitigated through the use of capacity-based agreements and minimum volume commitments.
In our G&P segment, we experience minimal impacts from seasonal fluctuations, which impact the demand for natural gas and NGLs and the related commodity prices caused by various factors including variations in weather patterns from year to year. Overall, our exposure to the seasonality fluctuations is limited due to the nature of our fee-based business.

40

Table of Contents
Liquidity and Capital Resources
Cash Flows
Our cash and cash equivalents were $2,426 million at September 30, 2024 and $1,048 million at December 31, 2023. The change in cash and cash equivalents was due to the factors discussed below. Net cash provided by (used in) operating activities, investing activities and financing activities were as follows:
 Nine Months Ended 
September 30,
(In millions)20242023
Net cash provided by (used in):
Operating activities$4,271 $3,908 
Investing activities(1,646)(727)
Financing activities(1,247)(2,459)
Total$1,378 $722 
Net cash provided by operating activities increased $363 million in the first nine months of 2024 compared to the same period of 2023, primarily due to improved results from operations during the first nine months of 2024 compared to the same period of 2023.
Net cash used in investing activities increased $919 million in the first nine months of 2024 compared to the same period of 2023, primarily due to the Utica Midstream Acquisition in the first quarter of 2024 and higher capital spending. The first nine months of 2024 also reflects the acquisition of additional interest in BANGL, LLC in the third quarter of 2024 as well as higher contributions to equity method investments, including a $92 million contribution to Dakota Access to fund our share of a scheduled debt repayment by the joint venture. The increases were partially offset by a $134 million cash distribution received in the second quarter of 2024, recorded as a return of capital, in connection with the Whistler Joint Venture Transaction.
Net cash used in financing activities decreased $1,212 million in the first nine months of 2024 compared to the same period of 2023. The decrease was primarily due to proceeds from the issuance of $1.65 billion aggregate principal amount of 2034 Senior Notes during the first nine months of 2024. This decrease was partially offset by the return of capital to unitholders through unit repurchases of $226 million, as well as higher distributions paid to unitholders of $204 million during the first nine months of 2024 compared to the same period of 2023, as a result of the 10 percent increase in our base distribution effective for the third quarter of 2023.
Adjusted Free Cash Flow
The following table provides a reconciliation of Adjusted FCF and Adjusted FCF after distributions from net cash provided by operating activities for the three and nine months ended September 30, 2024 and September 30, 2023.
Three Months Ended 
September 30,
Nine Months Ended 
September 30,
(In millions)2024202320242023
Net cash provided by operating activities(1)
$1,415 $1,244 $4,271 $3,908 
Adjustments to reconcile net cash provided by operating activities to adjusted free cash flow
Net cash used in investing activities(2)
(536)(236)(1,646)(727)
Contributions from MPC26 20 
Distributions to noncontrolling interests(11)(11)(33)(30)
Adjusted FCF876 1,004 2,618 3,171 
Distributions paid to common and preferred unitholders(873)(799)(2,623)(2,419)
Adjusted FCF after distributions$$205 $(5)$752 
(1)    The three months ended September 30, 2024 and September 30, 2023 include working capital builds of $40 million and $47 million, respectively. The nine months ended September 30, 2024 and September 30, 2023 include working capital draws of $55 million and $76 million, respectively.
(2)    The three and nine months ended September 30, 2024 include $210 million and $18 million related to the acquisition of additional interests in BANGL, LLC and Wink to Webster Pipeline LLC, respectively. The nine months ended September 30, 2024 include a $134 million cash distribution received in connection with the Whistler Joint Venture Transaction, $622 million, net of cash acquired, related to the Utica Midstream Acquisition and a contribution of $92 million to Dakota Access to fund our share of a debt repayment by the joint venture.
41

Table of Contents
Debt and Liquidity Overview
On May 20, 2024, MPLX issued $1.65 billion aggregate principal amount of the 2034 Senior Notes in an underwritten public offering. The 2034 Senior Notes were offered at a price to the public of 98.778 percent of par, with interest payable semi-annually in arrears, commencing on December 1, 2024. MPLX intends to use the net proceeds from the issuance of the 2034 Senior Notes to repay, redeem, or otherwise retire some or all of (i) MPLX’s outstanding $1,149 million aggregate principal amount of 4.875 percent senior notes due December 2024, (ii) MarkWest’s outstanding $1 million aggregate principal amount of 4.875 percent senior notes due December 2024 and (iii) MPLX’s outstanding $500 million aggregate principal amount of 4.000 percent senior notes due February 2025, and in the interim may use such net proceeds for general partnership purposes.
Our intention is to maintain an investment-grade credit profile. As of September 30, 2024, the credit ratings on our senior unsecured debt were as follows:
Rating AgencyRating
Moody’sBaa2 (stable outlook)
Standard & Poor’sBBB (stable outlook)
FitchBBB (stable outlook)
The ratings reflect the respective views of the rating agencies and should not be interpreted as a recommendation to buy, sell or hold our securities. Although it is our intention to maintain a credit profile that supports an investment grade rating, there is no assurance that these ratings will continue for any given period of time. The ratings may be revised or withdrawn entirely by the rating agencies if, in their respective judgments, circumstances so warrant. A rating from one rating agency should be evaluated independently of ratings from other rating agencies.
The agreements governing our debt obligations do not contain credit rating triggers that would result in the acceleration of interest, principal or other payments solely in the event that our credit ratings are downgraded. However, any downgrades in the credit ratings of our senior unsecured debt ratings to below investment grade ratings could, among other things, increase the applicable interest rates and other fees payable under the MPLX Credit Agreement and may limit our ability to obtain future financing, including refinancing existing indebtedness.
Our liquidity totaled $5.9 billion at September 30, 2024 consisting of:
September 30, 2024
(In millions)Total CapacityOutstanding BorrowingsAvailable
Capacity
MPLX Credit Agreement$2,000 $— $2,000 
MPC Loan Agreement1,500 — 1,500 
Total$3,500 $— 3,500 
Cash and cash equivalents2,426 
Total liquidity$5,926 
We expect our ongoing sources of liquidity to include cash generated from operations and borrowings under our revolving credit facilities and access to capital markets. We believe that cash generated from these sources will be sufficient to meet our short-term and long-term funding requirements, including working capital requirements, capital expenditure requirements, contractual obligations, and quarterly cash distributions. Our material future obligations include interest on debt, payments of debt principal, purchase obligations including contracts to acquire plant, property and equipment, and our operating leases and service agreements. We may also, from time to time, repurchase our senior notes or preferred units in the open market, in tender offers, in privately negotiated transactions or otherwise in such volumes, at market prices and upon such other terms as we deem appropriate and execute unit repurchases under our unit repurchase program.
MPC manages our cash and cash equivalents on our behalf directly with third-party institutions as part of the treasury services that it provides to us under our omnibus agreement. From time to time, we may also utilize other sources of liquidity, including the formation of joint ventures or sales of non-strategic assets.
MPLX’s credit agreement (the “MPLX Credit Agreement”) matures in July 2027 and contains certain representations and warranties, affirmative and restrictive covenants and events of default that we consider to be usual and customary for an agreement of this type. As of September 30, 2024, we were in compliance with such covenants.
MPLX is party to a loan agreement with MPC (the “MPC Loan Agreement”), which was renewed on July 31, 2024. The MPC Loan Agreement is now scheduled to expire, and borrowings under the loan agreement are scheduled to mature and become due and payable, on July 31, 2029, 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.
42

Table of Contents
Equity and Preferred Units Overview
Unit Repurchase Program
On August 2, 2022, we announced the board authorization for the repurchase of up to $1.0 billion of MPLX common units held by the public. The 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 suspended, discontinued, or restarted at any time.
Total unit repurchases were as follows for the respective periods:
Three Months Ended 
September 30,
Nine Months Ended 
September 30,
(In millions, except per unit data)2024202320242023
Number of common units repurchased1.8 — 5.5 — 
Cash paid for common units repurchased(1)
$76 $— $226 $— 
Average cost per unit(1)
$42.89 $— $41.32 $— 
(1)    Cash paid for common units repurchased and average cost per unit includes commissions paid to brokers during the period.
As of September 30, 2024, we had $620 million remaining under the unit repurchase authorization.
Series A Redeemable Preferred Unit Conversions
During the nine months ended September 30, 2024, certain Series A preferred unitholders exercised their rights to convert their Series A preferred units into approximately 21 million common units. Approximately 6 million Series A preferred units remain outstanding as of September 30, 2024.
Distributions
On October 29, 2024, MPLX declared a cash distribution for the third quarter of 2024, totaling $974 million, or $0.9565 per common unit. This distribution will be paid on November 15, 2024, to common unitholders of record on November 8, 2024. Although our partnership agreement requires that we distribute all of our available cash (as defined in the partnership agreement) each quarter, we do not otherwise have a legal obligation to distribute any particular amount per common unit. This rate will also be received by Series A preferred unitholders.
The allocation of total cash distributions is as follows for the three and nine months ended September 30, 2024 and September 30, 2023. 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, except per unit data)2024202320242023
Distribution declared:
Limited partner units - public$355 $301 $986 $849 
Limited partner units - MPC619 550 1,720 1,554 
Total LP distribution declared974 851 2,706 2,403 
Series A preferred units25 21 71 
Series B preferred units(1)
— — — 
Total distribution declared$980 $876 $2,727 $2,479 
Quarterly cash distributions declared per limited partner common unit$0.9565 $0.8500 $2.6565 $2.4000 
(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.
43

Table of Contents
Capital Expenditures
Our operations are capital intensive, requiring investments to expand, upgrade, enhance or maintain existing operations and to meet environmental and operational regulations. Our capital requirements consist of growth capital expenditures and maintenance capital expenditures. Growth capital expenditures are those incurred for acquisitions or capital improvements that we expect will increase our operating capacity for volumes gathered, processed, transported or fractionated or decrease operating expenses within our facilities or increase operating income over the long term. Examples of growth capital expenditures include costs to develop or acquire additional pipeline, terminal, processing or storage capacity. In general, growth capital includes costs that are expected to generate additional or new cash flow for MPLX. In contrast, maintenance capital expenditures are those made to replace partially or fully depreciated assets, to maintain the existing operating capacity of our assets and to extend their useful lives, or other capital expenditures that are incurred in maintaining existing system volumes and related cash flows.
MPLX’s initial capital investment plan for 2024 is $1.1 billion, net of reimbursements, which includes growth capital of $950 million and maintenance capital of $150 million. The capital outlook excludes a $92 million equity method investment contribution made in March 2024 for the repayment of MPLX’s share of the Dakota Access joint venture’s debt, which reduced our maximum potential undiscounted payments under the Contingent Equity Contribution Agreement. Growth capital expenditures and investments in affiliates during the nine months ended September 30, 2024, were primarily for gas processing plants in the Marcellus and Permian basins and gathering projects in the Marcellus, Utica and Permian basins. We continuously evaluate our capital plan and make changes as conditions warrant.
Our capital expenditures are shown in the table below:
 Nine Months Ended 
September 30,
(In millions)20242023
Capital expenditures:
Growth capital expenditures$569 $555 
Growth capital reimbursements(64)(119)
Investments in unconsolidated affiliates(1)
186 90 
Return of capital(4)— 
Capitalized interest(12)(10)
Total growth capital expenditures(2)
675 516 
Maintenance capital expenditures151 113 
Maintenance capital reimbursements(31)(20)
Capitalized interest(2)(1)
Total maintenance capital expenditures118 92 
Total growth and maintenance capital expenditures793 608 
Investments in unconsolidated affiliates(1)
(186)(90)
Return of capital— 
Growth and maintenance capital reimbursements(3)
95 139 
Decrease/(Increase) in capital accruals28 (6)
Capitalized interest14 11 
Additions to property, plant and equipment(1)
$748 $662 
(1)    Investments in unconsolidated affiliates for the nine months ended September 30, 2024, exclude $210 million and $18 million related to the acquisition of additional interests in BANGL, LLC and Wink to Webster Pipeline LLC, respectively. Investments in unconsolidated affiliates and additions to property, plant and equipment are shown as separate lines within investing activities in the Consolidated Statements of Cash Flows.
(2)    Total growth capital expenditures for the nine months ended September 30, 2024, exclude $622 million of acquisitions, net of cash acquired, and a $134 million cash distribution received in connection with the Whistler Joint Venture Transaction.
(3)    Growth capital reimbursements are generally included in changes in deferred revenue within operating activities in the Consolidated Statements of Cash Flows. Maintenance capital reimbursements are included in the Contributions from MPC line within financing activities in the Consolidated Statements of Cash Flows.
We participate in joint ventures, which, in turn, also invest in capital projects. Certain joint ventures require that we fund our proportionate share of capital expenditures through contributions to the joint venture, while others finance the projects at the joint venture level. Capital contributions will depend upon the joint ventures’ capital requirements, including funding capital projects or repayment of long-term obligations.
44

Table of Contents
Growth capital projects funded through debt at the joint venture level or through cash from operations of the joint venture do not require contributions by us. Our pro-rata share of these growth capital projects for our equity method investments are shown in the table below.
MPLX OwnershipNine Months Ended 
September 30,
(In millions, except ownership percentages)20242023
BANGL, LLC45%$84 $
MXP Parent, LLC(1)
5%47 22 
WPC Parent, LLC(2)
30%18 73 
All other43 33 
Total$192 $137 
(1)    Includes growth capital for Matterhorn Express Pipeline.
(2)    Disclosed amounts include growth capital related to WPC Parent, LLC, including the ADCC Pipeline lateral, Rio Bravo Pipeline, Whistler Pipeline, and Blackcomb Pipeline, in addition to MPLX’s 12.5 percent direct ownership interest in the Blackcomb Pipeline.
Debt at the joint venture level is typically secured by the assets owned by the joint venture and, unless otherwise noted, is non-recourse to MPLX other than with respect to our equity method investment. At September 30, 2024, debt held by our unconsolidated joint ventures based on our equity ownership percentage was $1.6 billion.
Cash Commitments
As of September 30, 2024, our material cash commitments included debt, finance and operating lease obligations, purchase obligations for services and to acquire property, plant and equipment, and other liabilities. During the nine months ended September 30, 2024, our debt obligations increased due to the issuance of the $1.65 billion aggregate principal amount of 2034 Senior Notes, described in Liquidity and Capital Resources - Debt and Liquidity Overview. There were no other material changes to our cash commitments outside the ordinary course of business.
Off-Balance Sheet Arrangements
Off-balance sheet arrangements comprise those arrangements that may potentially impact our liquidity, capital resources and results of operations, even though such arrangements are not recorded as liabilities under GAAP. Our off-balance sheet arrangements are limited to guarantees that are described in Note 16 of the unaudited consolidated financial statements and indemnities as disclosed in our Annual Report on Form 10-K for the year ended December 31, 2023.
Although these arrangements serve a variety of our business purposes, we are not dependent on them to maintain our liquidity and capital resources, and we are not aware of any circumstances that are reasonably likely to cause the off-balance sheet arrangements to have a material adverse effect on our liquidity and capital resources.
Transactions with Related Parties
As of September 30, 2024, MPC owned our general partner and an approximate 64 percent limited partner interest in us. We perform a variety of services for MPC related to the transportation of crude and refined products, including renewables, via pipeline or marine, as well as terminal services, storage services and fuels distribution and marketing services, among others. The services that we provide may be based on regulated tariff rates or on contracted rates. In addition, MPC performs certain services for us related to information technology, engineering, legal, accounting, treasury, human resources and other administrative services.
The below table shows the percentage of Total revenues and other income as well as Total costs and expenses with MPC:
Three Months Ended 
September 30,
Nine Months Ended 
September 30,
2024202320242023
Total revenues and other income(1)
49 %49 %50 %50 %
Total costs and expenses27 %29 %27 %28 %
(1)    The nine months ended September 30, 2024 excludes gain on dilution of ownership interest related to the Whistler Joint Venture Transaction.
For further discussion of agreements and activity with MPC and related parties see Item 1. Business in our Annual Report on Form 10-K for the year ended December 31, 2023, and Note 5 to the unaudited consolidated financial statements.
Environmental Matters and Compliance Costs
We have incurred and may continue to incur substantial capital, operating and maintenance, and remediation expenditures as a result of environmental laws and regulations. If these expenditures, as with all costs, are not ultimately reflected in the prices of our products and services, our operating results will be adversely affected. We believe that substantially all of our competitors
45

Table of Contents
must comply with similar environmental laws and regulations. However, the specific impact on each competitor may vary depending on a number of factors, including, but not limited to, the age and location of its operating facilities.
As previously disclosed in our Annual Report on Form 10-K for the year ended December 31, 2023, actual expenditures may vary as the number and scope of environmental projects are revised as a result of improved technology or changes in regulatory requirements. There have been no material changes to our environmental matters and compliance costs since our Annual Report on Form 10-K for the year ended December 31, 2023.
Tax Matters
Our U.S. federal income tax returns for the years 2019 through 2022 are currently under examination by the Internal Revenue Service.
Critical Accounting Estimates
As of September 30, 2024, there have been no significant changes to our critical accounting estimates since our Annual Report on Form 10-K for the year ended December 31, 2023.
Accounting Standards Not Yet Adopted
As discussed in Note 2 to the unaudited consolidated financial statements, certain new financial accounting pronouncements will be effective for our financial statements in the future.
Item 3. Quantitative and Qualitative Disclosures about Market Risk
We are exposed to market risks related to the volatility of commodity prices. We employ various strategies, including the potential use of commodity derivative instruments, to economically hedge the risks related to these price fluctuations. We are also exposed to market risks related to changes in interest rates. As of September 30, 2024, we did not have any open financial or commodity derivative instruments to hedge the economic risks related to interest rate fluctuations; however, we continually monitor the market and our exposure and may enter into these arrangements in the future.
Commodity Price Risk
The information about commodity price risk for the three and nine months ended September 30, 2024 does not differ materially from that discussed in Item 7A. Quantitative and Qualitative Disclosures about Market Risk of our Annual Report on Form 10-K for the year ended December 31, 2023.
Outstanding Derivative Contracts
See Notes 10 and 11 to the unaudited consolidated financial statements for more information about the fair value measurement of our derivative instruments, as well as the amounts recorded in our consolidated balance sheets and statements of income. We do not designate any of our commodity derivative instruments as hedges for accounting purposes.
Interest Rate Risk and Sensitivity Analysis
Sensitivity analysis of the effect of a hypothetical 100-basis-point change in interest rates on outstanding third-party debt, excluding finance leases, is provided in the following table. Fair value of cash and cash equivalents, receivables, accounts payable and accrued interest approximate carrying value and are relatively insensitive to changes in interest rates due to the short-term maturity of the instruments. Accordingly, these instruments are excluded from the table.
(In millions)
Fair Value as of September 30, 2024(1)
Change in Fair Value(2)
Change in Income Before Income Taxes for the Nine Months Ended September 30, 2024(3)
Outstanding debt
Fixed-rate$21,494 $1,649 N/A
Variable-rate(4)
$— $— $— 
(1)    Fair value was based on market prices, where available, or current borrowing rates for financings with similar terms and maturities.
(2)    Assumes a 100-basis-point decrease in the weighted average yield-to-maturity at September 30, 2024.
(3)    Assumes a 100-basis-point change in interest rates. The change to income before income taxes was based on the weighted average balance of all outstanding variable-rate debt for the nine months ended September 30, 2024.
(4)    MPLX had no outstanding borrowings on the MPLX Credit Agreement as of September 30, 2024.
At September 30, 2024, our portfolio of third‑party debt consisted of fixed-rate instruments and outstanding borrowings, if any, under the MPLX Credit Agreement. The fair value of our fixed-rate debt is relatively sensitive to interest rate fluctuations. Our sensitivity to interest rate declines and corresponding increases in the fair value of our debt portfolio unfavorably affects our results of operations and cash flows only when we elect to repurchase or otherwise retire fixed-rate debt at prices above carrying
46

Table of Contents
value. Interest rate fluctuations generally do not impact the fair value of borrowings under our MPLX Credit Agreement, but may affect our results of operations and cash flows.
See Note 10 in the unaudited consolidated financial statements for additional information on the fair value of our debt.
Item 4. Controls and Procedures
Disclosure Controls and Procedures
An evaluation of the effectiveness of the design and operation of our disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended (the “Exchange Act”)), was carried out under the supervision and with the participation of our management, including the chief executive officer and chief financial officer of our general partner. Based upon that evaluation, the chief executive officer and chief financial officer of our general partner concluded that the design and operation of these disclosure controls and procedures were effective as of September 30, 2024, the end of the period covered by this Quarterly Report on Form 10-Q.
Changes in Internal Control over Financial Reporting
During the quarter ended September 30, 2024, there were no changes in our internal control over financial reporting that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.
47

Table of Contents
PART II – OTHER INFORMATION
Item 1. Legal Proceedings
We are the subject of, or a party to, a number of pending or threatened legal actions, contingencies and commitments involving a variety of matters, including laws and regulations relating to the environment. While it is possible that an adverse result in one or more of the lawsuits or proceedings in which we are a defendant could be material to us, based upon current information and our experience as a defendant in other matters, we believe that these lawsuits and proceedings, individually or in the aggregate, will not have a material adverse effect on our consolidated results of operations, financial position or cash flows.
Item 103 of Regulation S-K promulgated by the SEC requires disclosure of certain environmental matters when a governmental authority is a party to the proceedings and such proceedings involve potential monetary sanctions, unless we reasonably believe that the matter will result in no monetary sanctions, or in monetary sanctions, exclusive of interest and costs, of less than a specified threshold. We use a threshold of $1 million for this purpose.
There have been no material changes to the legal matters previously disclosed in our Annual Report on Form 10-K for the year ended December 31, 2023.
Item 1A. Risk Factors
There have been no material changes from the risk factors previously disclosed in our Annual Report on Form 10-K for the year ended December 31, 2023.
Item 2. Unregistered Sales of Equity Securities and Use of Proceeds
The following table sets forth a summary of our purchases during the quarter ended September 30, 2024, of equity securities that are registered by MPLX pursuant to Section 12 of the Exchange Act.
Millions of Dollars
PeriodTotal Number of Common Units Purchased
Average Price
Paid per
Common Unit
(1)
Total Number of Common Units Purchased as Part of Publicly Announced Plans or Programs
Maximum Dollar Value of Common Units that May Yet Be Purchased Under the Plans or Programs(2)(3)
7/1/2024-7/31/2024451,060 $42.67 451,060 $677 
8/1/2024-8/31/2024628,151 42.20 628,151 650 
9/1/2024-9/30/2024696,554 43.66 696,554 $620 
Total1,775,765 $42.89 1,775,765 
(1)Amounts in this column reflect the weighted average price paid for units purchased under our unit repurchase authorization. The weighted average price includes any commissions paid to brokers during the relevant period.
(2)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.
(3)The maximum dollar value remaining has been reduced by the amount of any commissions paid to brokers during the relevant period.
Item 5. Other Information
During the quarter ended September 30, 2024, no director or officer (as defined in Rule 16a-1(f) promulgated under the Exchange Act) of MPLX adopted or terminated a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement” (as each term is defined in Item 408 of Regulation S-K).
48

Table of Contents
Item 6. Exhibits
  Incorporated by Reference From  
Exhibit
Number
Exhibit DescriptionFormExhibitFiling DateSEC File No.Filed
Herewith
Furnished
Herewith
3.1S-13.17/2/2012333-182500
3.2S-1/A3.210/9/2012333-182500
3.38-K3.12/3/2021001-35714
10.110-Q10.28/6/2024001-35714
10.2X
10.3X
10.4*X
31.1X
31.2X
32.1X
32.2X
101.INSXBRL Instance Document: The instance document does not appear in the interactive data file because its XBRL tags are embedded within the Inline XBRL document.
101.SCHInline XBRL Taxonomy Extension Schema Document.X
101.CALInline XBRL Taxonomy Extension Calculation Linkbase Document.X
101.DEFInline XBRL Taxonomy Extension Definition Linkbase Document.X
101.LABInline XBRL Taxonomy Extension Label Linkbase Document.X
101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document.X
104Cover Page Interactive Data File (formatted as Inline XBRL and contained in Exhibit 101).
* Indicates management contract or compensatory plan, contract or arrangement in which one or more directors or executive officers of the Registrant may be participants.
49

Table of Contents
SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.
 
MPLX LP
By:MPLX GP LLC
Its general partner
Date: November 5, 2024By:/s/ Kelly D. Wright
Kelly D. Wright
Vice President and Controller of MPLX GP LLC (the general partner of MPLX LP)

50