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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
 _____________________________________________
FORM 10-Q
 ____________________________________________
(Mark One)
QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the quarterly period ended March 31, 2021
OR
TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the transition period from                      to                     
Commission file number 001-35714
_____________________________________________ 
MPLX LP
(Exact name of registrant as specified in its charter)
 _____________________________________________
Delaware27-0005456
(State or other jurisdiction of
incorporation or organization)
 (I.R.S. Employer
Identification No.)
200 E. Hardin Street,Findlay,Ohio 45840
(Address of principal executive offices)(Zip code)

(419) 421-2414
(Registrant’s telephone number, including area code)
 _____________________________________________
Securities Registered pursuant to Section 12(b) of the Act
Title of each class Trading symbol(s)Name of each exchange on which registered
Common Units Representing Limited Partnership InterestsMPLXNew York Stock Exchange
Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes  x     No  ¨

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

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

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

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

MPLX LP had 1,029,527,052 common units outstanding at April 30, 2021.


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 Page

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

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Table of Contents
Glossary of Terms

The abbreviations, acronyms and industry technology used in this report are defined as follows.
ASCAccounting Standards Codification
ASUAccounting Standards Update
BarrelOne stock tank barrel, or 42 United States gallons of liquid volume, used in reference to crude oil or other liquid hydrocarbons
Bcf/dOne billion cubic feet per day
BtuOne British thermal unit, an energy measurement
CondensateA natural gas liquid with a low vapor pressure mainly composed of propane, butane, pentane and heavier hydrocarbon fractions
DCF (a non-GAAP financial measure)Distributable Cash Flow
EBITDA (a non-GAAP financial measure)Earnings Before Interest, Taxes, Depreciation and Amortization
FASBFinancial Accounting Standards Board
GAAPAccounting principles generally accepted in the United States of America
LIBORLondon Interbank Offered Rate
mbpdThousand barrels per day
MergerMPLX acquisition by merger of Andeavor Logistics LP (“ANDX”) on July 30, 2019
MMBtuOne million British thermal units, an energy measurement
MMcf/dOne million cubic feet of natural gas per day
NGLNatural gas liquids, such as ethane, propane, butanes and natural gasoline
NYSENew York Stock Exchange
Realized derivative gain/lossThe gain or loss recognized when a derivative matures or is settled
SECUnited States Securities and Exchange Commission
Unrealized derivative gain/lossThe gain or loss recognized on a derivative due to changes in fair value prior to the instrument maturing or settling
VIEVariable interest entity
Wholesale ExchangeThe transfer to MPC of the Western wholesale distribution business, which MPLX acquired as a result of its acquisition of ANDX, on July 31, 2020.

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Table of Contents
Part I—Financial Information

Item 1. Financial Statements
MPLX LP
Consolidated Statements of Income (Unaudited)
Three Months Ended 
March 31,
(In millions, except per unit data)20212020
Revenues and other income:
Service revenue$589 $612 
Service revenue - related parties872 928 
Service revenue - product related77 39 
Rental income99 96 
Rental income - related parties242 234 
Product sales282 169 
Product sales - related parties42 33 
Income/(loss) from equity method investments(1)
70 (1,184)
Other income1 1 
Other income - related parties65 64 
Total revenues and other income2,339 992 
Costs and expenses:
Cost of revenues (excludes items below)273 368 
Purchased product costs276 135 
Rental cost of sales32 35 
Rental cost of sales - related parties39 46 
Purchases - related parties298 276 
Depreciation and amortization329 325 
Impairment expense 2,165 
General and administrative expenses86 97 
Other taxes32 31 
Total costs and expenses1,365 3,478 
Income/(loss) from operations974 (2,486)
Related party interest and other financial costs 3 
Interest expense (net of amounts capitalized of $5 million, $13 million, respectively)
198 211 
Other financial costs27 16 
Income/(loss) before income taxes749 (2,716)
Provision for income taxes1  
Net income/(loss)748 (2,716)
Less: Net income attributable to noncontrolling interests9 8 
Net income/(loss) attributable to MPLX LP739 (2,724)
Less: Series A preferred unit distributions20 20 
Less: Series B preferred unit distributions11 11 
Limited partners’ interest in net income/(loss) attributable to MPLX LP$708 $(2,755)
Per Unit Data (See Note 6)
Net income/(loss) attributable to MPLX LP per limited partner unit:
Common - basic$0.68 $(2.60)
Common - diluted$0.68 $(2.60)
Weighted average limited partner units outstanding:
Common - basic1,037 1,058 
Common - diluted1,037 1,058 

(1)     The 2020 period includes $1,264 million of impairment expense. See Note 4.

The accompanying notes are an integral part of these consolidated financial statements.
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Table of Contents
MPLX LP
Consolidated Statements of Comprehensive Income (Unaudited)
Three Months Ended 
March 31,
(In millions)20212020
Net income/(loss)$748 $(2,716)
Other comprehensive income/(loss), net of tax:
Remeasurements of pension and other postretirement benefits related to equity method investments, net of tax(2)(1)
Comprehensive income/(loss)746 (2,717)
Less comprehensive income attributable to:
Noncontrolling interests9 8 
Comprehensive income/(loss) attributable to MPLX LP$737 $(2,725)


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

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MPLX LP
Consolidated Balance Sheets (Unaudited)
 
(In millions)March 31, 2021December 31, 2020
Assets
Current assets:
Cash and cash equivalents$24 $15 
Receivables, net523 452 
Current assets - related parties650 677 
Inventories128 118 
Assets held for sale 188 
Other current assets49 65 
Total current assets1,374 1,515 
Equity method investments4,040 4,036 
Property, plant and equipment, net20,996 21,218 
Intangibles, net927 959 
Goodwill7,657 7,657 
Right of use assets, net296 309 
Noncurrent assets - related parties676 672 
Other noncurrent assets64 48 
Total assets36,030 36,414 
Liabilities
Current liabilities:
Accounts payable162 152 
Accrued liabilities233 194 
Current liabilities - related parties338 356 
Accrued property, plant and equipment58 84 
Long-term debt due within one year2 764 
Accrued interest payable189 222 
Operating lease liabilities63 63 
Liabilities held for sale 101 
Other current liabilities151 150 
Total current liabilities1,196 2,086 
Long-term deferred revenue332 314 
Long-term liabilities - related parties279 283 
Long-term debt20,052 19,375 
Deferred income taxes11 12 
Long-term operating lease liabilities230 244 
Deferred credits and other liabilities112 115 
Total liabilities22,212 22,429 
Commitments and contingencies (see Note 21)
Series A preferred units968 968 
Equity
Common unitholders - public (385 million and 391 million units issued and outstanding)
9,226 9,384 
Common unitholders - MPC (647 million and 647 million units issued and outstanding)
2,796 2,792 
Series B preferred units (.6 million and .6 million units issued and outstanding)
601 611 
Accumulated other comprehensive loss(17)(15)
Total MPLX LP partners’ capital12,606 12,772 
Noncontrolling interests244 245 
Total equity12,850 13,017 
Total liabilities, preferred units and equity$36,030 $36,414 

The accompanying notes are an integral part of these consolidated financial statements.
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MPLX LP
Consolidated Statements of Cash Flows (Unaudited)
Three Months Ended 
March 31,
(In millions)20212020
Increase/(decrease) in cash, cash equivalents and restricted cash
Operating activities:
Net income/(loss)$748 $(2,716)
Adjustments to reconcile net income/(loss) to net cash provided by operating activities:
Amortization of deferred financing costs17 14 
Depreciation and amortization329 325 
Impairment expense 2,165 
(Income)/loss from equity method investments(1)
(70)1,184 
Distributions from unconsolidated affiliates119 119 
Changes in:
Current receivables(67)71 
Inventories(11)3 
Fair value of derivatives3 (15)
Current accounts payable and accrued liabilities26 (142)
Current assets/current liabilities - related parties(8)(52)
Right of use assets/operating lease liabilities(1)(4)
Deferred revenue24 27 
All other, net15 30 
Net cash provided by operating activities1,124 1,009 
Investing activities:
Additions to property, plant and equipment(126)(379)
Disposal of assets70 39 
Investments in unconsolidated affiliates(35)(91)
Distributions from unconsolidated affiliates - return of capital 69 
All other, net1  
Net cash used in investing activities(90)(362)
Financing activities:
Long-term debt - borrowings1,910 1,325 
       - repayments(2,020)(581)
Related party debt - borrowings2,241 1,667 
        - repayments(2,241)(2,261)
Unit repurchases(155) 
Distributions to noncontrolling interests(10)(9)
Distributions to Series A preferred unitholders(20)(20)
Distributions to Series B preferred unitholders(21)(21)
Distributions to unitholders and general partner(713)(717)
Contributions from MPC7 14 
All other, net(3)(2)
Net cash used in financing activities(1,025)(605)
Net increase in cash, cash equivalents and restricted cash9 42 
Cash, cash equivalents and restricted cash at beginning of period15 15 
Cash, cash equivalents and restricted cash at end of period$24 $57 

(1)     The 2020 period includes $1,264 million of impairment expense. See Note 4.

The accompanying notes are an integral part of these consolidated financial statements.
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MPLX LP
Consolidated Statements of Equity (Unaudited)

 Partnership  
(In millions)Common
Unit-holders
Public
Common
Unit-holder
MPC
Series B Preferred Unit-holdersAccumulated Other Comprehensive LossNon-controlling
Interests
Total
Balance at December 31, 2019$10,800 $4,968 $611 $(15)$249 $16,613 
Net (loss)/income (excludes amounts attributable to preferred units)(1,022)(1,733)11  8 (2,736)
Distributions to:
Unitholders(271)(446)(21)  (738)
Noncontrolling interests    (9)(9)
Contributions from:
MPC 225    225 
Other2   (1) 1 
Balance at March 31, 20209,509 3,014 601 (16)248 13,356 
Balance at December 31, 20209,384 2,792 611 (15)245 13,017 
Net income (excludes amounts attributable to preferred units)266 443 11  9 729 
Unit Repurchases(155)    (155)
Distributions to:
Unitholders(269)(445)(21)  (735)
Noncontrolling interests    (10)(10)
Contributions from:
MPC 7    7 
Other (1) (2) (3)
Balance at March 31, 2021$9,226 $2,796 $601 $(17)$244 $12,850 

The accompanying notes are an integral part of these consolidated financial statements.
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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. References in this report to “MPLX LP,” “MPLX,” “the Partnership,” “we,” “ours,” “us,” or like terms refer to MPLX LP and its subsidiaries. References to “MPC” refer collectively to Marathon Petroleum Corporation as our sponsor and its subsidiaries, other than the Partnership. We are engaged in the transportation, storage and distribution of crude oil, asphalt and refined petroleum products; the gathering, processing and transportation of natural gas; and the gathering, transportation, fractionation, storage and marketing of NGLs. MPLX’s principal executive office is located in Findlay, Ohio.

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, asphalt and refined petroleum products; and Gathering and Processing (“G&P”), which relates primarily to natural gas and NGLs. See Note 9 for additional information regarding the operations and results of these segments.

On July 31, 2020, MPLX completed the exchange of Western Refining Wholesale, LLC (“WRW”) to Western Refining Southwest, Inc. (now known as Western Refining Southwest LLC) (“WRSW”), a wholly owned subsidiary of MPC, in exchange for the redemption of 18,582,088 MPLX common units held by WRSW (the “Wholesale Exchange”). See Note 3 for additional information regarding the Wholesale Exchange. These financial statements include the results of WRSW through July 31, 2020.

Impairments – During the first quarter of 2021, we have seen improvement in the environment in which our business operates as COVID-19 impacts are beginning to subside. The increased availability of vaccinations, coupled with an easing of COVID-19 restrictions in certain areas, has been followed by an increase in economic activity, the opening of many businesses and schools and an increase in in-person interaction and associated travel. No additional events or circumstances arose during the first quarter of 2021 that would indicate potential impairment beyond those recognized in 2020 as noted below.

During the first quarter of 2020, the overall deterioration in the economy and the environment in which MPLX and its customers operate, as well as a sustained decrease in unit price, were considered triggering events at that time resulting in impairments of the carrying value of certain assets. We recognized impairments related to goodwill, certain equity method investments and certain long-lived assets (including intangibles), within our G&P segment. Many of our producer customers refined and updated production forecasts in response to the environment at that time, which impacted their expected future demand for our services, including the future utilization of our assets. Additionally, certain of our contracts have commodity price exposure, including NGL prices, which experienced increased volatility as noted above. The table below provides information related to the impairments recognized during the first quarter of 2020 as well as the corresponding footnote where additional information can be found.
(In millions)ImpairmentFootnote Reference
Goodwill$1,814 12
Equity method investments1,264 4
Intangibles, net177 12
Property, plant and equipment, net174 11
Total impairments$3,429 

Basis of PresentationThe accompanying 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.

These interim consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in the Annual Report on Form 10-K for the year ended December 31, 2020. The results of operations for the three months ended March 31, 2021 are not necessarily indicative of the results to be expected for the full year.

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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 investments, 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.

In preparing the Consolidated Statements of Equity, net income attributable to MPLX LP is allocated to Series A and Series B preferred unitholders based on a fixed distribution schedule. Distributions, although earned, are not accrued until declared. The allocation of net income attributable to MPLX LP for purposes of calculating net income per limited partner unit is described in Note 6.

2. Accounting Standards

Recently Adopted

We did not adopt any ASUs during the first three months of 2021 that are expected to have a material impact to our financial statements or financial statement disclosures.
3. Acquisitions and Dispositions

Sale of Javelina Assets and Liabilities

On February 12, 2021, MarkWest Energy Operating Company, L.L.C., (“MarkWest Energy”) a wholly owned subsidiary of MPLX, completed the sale of all of MarkWest Energy’s equity interests in MarkWest Javelina Company L.L.C., MarkWest Javelina Pipeline Company L.L.C., and MarkWest Gas Services L.L.C. (collectively, “Javelina”) pursuant to the terms of an Equity Purchase Agreement entered into with a third party on December 23, 2020. The agreement included adjustments for working capital as well as an earnout provision based on the performance of the assets. No gain or loss was recorded on the sale. The estimated value of the earnout provision was recorded as a contingent asset shown within “Other noncurrent assets” on the Consolidated Balance Sheet as of March 31, 2021. Javelina’s assets and liabilities sold are shown on the Consolidated Balance Sheet as “Assets held for sale” and “Liabilities held for sale” for the year ended December 31, 2020. Prior to the sale, Javelina was reported within the G&P segment.

Wholesale Exchange

On July 31, 2020, MPLX entered into a Redemption Agreement (the “Redemption Agreement”) with WRSW, a wholly owned subsidiary of MPC, pursuant to which MPLX agreed to transfer to WRSW all of the outstanding membership interests in WRW in exchange for the redemption of MPLX common units held by WRSW. The transaction effected the transfer to MPC of the Western wholesale distribution business that MPLX acquired as a result of its acquisition of ANDX. Per the terms of the Redemption Agreement, MPLX redeemed 18,582,088 common units (the “Redeemed Units”) held by WRSW on July 31, 2020. The number of Redeemed Units was calculated by dividing WRW’s aggregate valuation of $340 million by the simple average of the volume weighted average NYSE prices of an MPLX common unit for the ten trading days ending at market close on July 27, 2020. MPLX canceled the Redeemed Units immediately following the Wholesale Exchange. The carrying value of the net assets of WRW transferred to MPC was approximately $90 million as of July 31, 2020, resulting in $250 million being recorded to “Common Unit-holder MPC” within the Consolidated Statements of Equity, netted against the fair value of the redeemed units. Included within the $90 million carrying value of the WRW net assets was approximately $65 million of goodwill.


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4. Investments and Noncontrolling Interests

The following table presents MPLX’s equity method investments at the dates indicated:
Ownership as ofCarrying value at
March 31,March 31,December 31,
(In millions, except ownership percentages)202120212020
L&S
MarEn Bakken Company LLC(1)
25%$462 $465 
Illinois Extension Pipeline Company, L.L.C.35%259 254 
LOOP LLC41%257 252 
Andeavor Logistics Rio Pipeline LLC(2)
67%193 194 
Minnesota Pipe Line Company, LLC17%187 188 
Whistler Pipeline LLC(2)
38%187 185 
Explorer Pipeline Company25%69 72 
W2W Holdings LLC(2)(3)
50%73 72 
Other(2)
105 103 
Total L&S1,792 1,785 
G&P
MarkWest Utica EMG, L.L.C.(2)
57%696 698 
Sherwood Midstream LLC(2)
50%552 557 
MarkWest EMG Jefferson Dry Gas Gathering Company, L.L.C.(2)
67%313 307 
Rendezvous Gas Services, L.L.C.(2)
78%157 159 
Sherwood Midstream Holdings LLC(2)
51%145 148 
Centrahoma Processing LLC40%137 145 
Other(2)
248 237 
Total G&P2,248 2,251 
Total$4,040 $4,036 
(1)    The investment in MarEn Bakken Company LLC includes our 9.19 percent indirect interest in a joint venture (“Dakota Access”) that owns and operates the Dakota Access Pipeline and Energy Transfer Crude Oil Pipeline projects, collectively referred to as the Bakken Pipeline system or DAPL.    
(2)    Investments deemed to be VIEs. Some investments included within “Other” have also been deemed to be VIEs.
(3)    Through our ownership interest in W2W Holdings LLC, we have a 15 percent equity interest Wink to Webster Pipeline LLC.

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 and as such we have determined that these entities should not be consolidated and apply the equity method of accounting with respect to our investments in each entity.

Sherwood Midstream LLC (“Sherwood Midstream”) has been deemed the primary beneficiary of Sherwood Midstream Holdings LLC (Sherwood Midstream Holdings”) due to its controlling financial interest through its authority to manage the joint venture. As a result, Sherwood Midstream consolidates Sherwood Midstream Holdings. Therefore, MPLX also reports its portion of Sherwood Midstream Holdings’ net assets as a component of its investment in Sherwood Midstream. As of March 31, 2021, MPLX has a 24.55 percent indirect ownership interest in Sherwood Midstream Holdings through Sherwood Midstream.

MPLX’s maximum exposure to loss as a result of its involvement with equity method investments includes its equity investment, any additional capital contribution commitments and any operating expenses incurred by the subsidiary operator in excess of its compensation received for the performance of the operating services. MPLX did not provide any financial support to equity method investments that it was not contractually obligated to provide during the three months ended March 31, 2021.


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During the first quarter of 2020, we recorded an other than temporary impairment for three joint ventures in which we have an interest as discussed in Note 1. Impairment of these investments was $1,264 million, of which $1,251 million was related to MarkWest Utica EMG, L.L.C. and its investment in Ohio Gathering Company, L.L.C. The impairment was recorded through “Income from equity method investments.” The impairments were largely due to a reduction in forecasted volumes gathered and processed by the systems operated by the joint ventures. No additional impairments have been recorded since that time.

Summarized financial information for MPLX’s equity method investments for the three months ended March 31, 2021 and 2020 is as follows:
Three Months Ended March 31, 2021
(In millions)VIEsNon-VIEsTotal
Revenues and other income$163 $284 $447 
Costs and expenses107 131 238 
Income from operations56 153 209 
Net income64 140 204 
Income from equity method investments(1)
$39 $31 $70 
(1)    Includes the impact of any basis differential amortization or accretion.
Three Months Ended March 31, 2020
(In millions)VIEsNon-VIEsTotal
Revenues and other income$(217)$337 $120 
Costs and expenses104 132 236 
(Loss)/income from operations(321)205 (116)
Net (loss)/income(337)186 (151)
(Loss)/income from equity method investments(1)
$(1,222)$38 $(1,184)
(1)    Includes the impact of any basis differential amortization or accretion in addition to the impairment of $1,264 million.

Summarized balance sheet information for MPLX’s equity method investments as of March 31, 2021 and December 31, 2020 is as follows:
March 31, 2021
(In millions)VIEsNon-VIEsTotal
Current assets$312 $321 $633 
Noncurrent assets7,266 4,967 12,233 
Current liabilities338 194 532 
Noncurrent liabilities$2,053 $853 $2,906 

December 31, 2020
(In millions)VIEsNon-VIEsTotal
Current assets$530 $318 $848 
Noncurrent assets6,889 4,997 11,886 
Current liabilities323 187 510 
Noncurrent liabilities$1,904 $830 $2,734 

As of March 31, 2021 and December 31, 2020, the underlying net assets of MPLX’s investees in the G&P segment exceeded the carrying value of its equity method investments by approximately $56 million and $57 million, respectively. As of March 31, 2021 and December 31, 2020, the carrying value of MPLX’s equity method investments in the L&S segment exceeded the underlying net assets of its investees by $331 million.

At March 31, 2021 and December 31, 2020, the G&P basis difference was being amortized into net income over the remaining estimated useful lives of the underlying assets, except for $31 million of excess related to goodwill. At March 31, 2021 and December 31, 2020, the L&S basis difference was being amortized into net income over the remaining estimated useful lives of the underlying assets, except for $167 million of excess related to goodwill.

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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, 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; as well as reimbursements for certain direct and indirect costs. MPC has also committed to provide a fixed fee for 100 percent of available capacity for boats, barges and third-party chartered equipment under the marine transportation service agreement. MPLX also has a keep-whole commodity agreement with MPC under which MPC pays us a processing fee for NGLs related to keep-whole agreements and delivers shrink gas to the producers on our behalf. We pay MPC a marketing fee in exchange for assuming the commodity risk. Additionally, MPLX has obligations to MPC for services provided to MPLX by MPC under omnibus and employee services-type agreements as well as other various agreements.

Related Party Loan

MPLX is party to a loan agreement with MPC Investment LLC (“MPC Investment”) (the “MPC Loan Agreement”). Under the terms of the agreement, MPC Investment extends loans to MPLX on a revolving basis as requested by MPLX and as agreed to by MPC Investment. The borrowing capacity of the MPC Loan Agreement is $1.5 billion aggregate principal amount of all loans outstanding at any one time. The loan agreement is scheduled to expire, and borrowings under the loan agreement are scheduled to mature and become due and payable on July 31, 2024, provided that MPC Investment 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 LIBOR plus 1.25 percent or such lower rate as would be applicable to such loans under the MPLX Credit Agreement as discussed in Note 15. Activity on the MPC Loan Agreement was as follows:
(In millions)Three Months Ended March 31, 2021Year Ended December 31, 2020
Borrowings$2,241 $6,264 
Average interest rate of borrowings1.371 %2.278 %
Repayments$2,241 $6,858 
Outstanding balance at end of period(1)
$ $ 
(1)     Included in “Current liabilities - related parties” on the Consolidated Balance Sheets.

Related Party Revenue

Related party sales to MPC consist of crude oil and refined products pipeline and trucking transportation services based on tariff/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.

Revenue received from related parties included on the Consolidated Statements of Income was as follows:
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 Three Months Ended March 31,
(In millions)20212020
Service revenues - related parties
MPC$871 $927 
Other1 1 
Total Service revenue - related parties872 928 
Rental income - related parties
MPC242 234 
Product sales - related parties(1)
MPC42 33 
Other income - related parties
MPC49 48 
Other16 16 
Total Other income - related parties$65 $64 
(1)     There were additional product sales to MPC that 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 months ended March 31, 2021 and March 31, 2020, these sales totaled $168 million and $173 million, respectively.

Related Party Expenses

MPC provides executive management services and certain general and administrative services to MPLX under the terms of our omnibus agreements (“Omnibus charges”). Omnibus charges included in “Rental cost of sales - related parties” primarily relate to services that support MPLX’s rental operations and maintenance of assets available for rent. Omnibus charges included in “Purchases - related parties” primarily relate to services that support MPLX’s operations and maintenance activities, as well as compensation expenses. Omnibus charges included in “General and administrative expenses” primarily relate to services that support MPLX’s executive management, accounting and human resources activities. MPLX also obtains employee services from MPC under employee services agreements (“ESA charges”). ESA charges for personnel directly involved in or supporting operations and maintenance activities related to rental services are classified as “Rental cost of sales - related parties.” ESA charges for personnel directly involved in or supporting operations and maintenance activities related to other services are classified as “Purchases - related parties.” ESA charges for personnel involved in executive management, accounting and human resources activities are classified as “General and administrative expenses.” I