MPLX 10-Q Quarterly Report Sept. 30, 2025

MPLX LP

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mplx-20250930

Table of Contents

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

_____________________________________________

FORM 10-Q

____________________________________________


(Mark One)
☒			QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended September 30, 2025


☐			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)

_____________________________________________

Delaware

27-0005456

(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 ) 422-2121

(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 Interests	MPLX	New 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 ☑ 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 ☑ 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 filer

☑

Accelerated filer

☐

Non-accelerated filer

☐

Smaller reporting company

☐

Emerging growth company

☐

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

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

MPLX LP had 1,017,065,152 common units outstanding as of October 31, 2025.

Table of Contents


		Page
PART I – FINANCIAL INFORMATION
Item 1.	Financial Statements:
	Consolidated Statements of Income (Unaudited)	3
	Consolidated Statements of Comprehensive Income (Unaudited)	4
	Consolidated Balance Sheets (Unaudited)	5
	Consolidated Statements of Cash Flows (Unaudited)	6
	Consolidated Statements of Equity and Series A Preferred Units (Unaudited)	7
	Notes to Consolidated Financial Statements (Unaudited)	8
	1. Description of the Business and Basis of Presentation	8
	2. Accounting Standards	8
	3. Acquisitions and Other Transactions	8
	4. Equity Method Investments	12
	5. Related Party Agreements and Transactions	13
	6. Equity	14
	7. Net Income Per Limited Partner Unit	15
	8. Segment Information	16
	9. Property, Plant and Equipment	18
	10. Fair Value Measurements	18
	11. Derivatives	19
	12. Debt	20
	13. Net Interest and Other Financial Costs	21
	14. Revenue	22
	15. Supplemental Cash Flow Information	25
	16. Commitments and Contingencies	25

Item 2.	Management’s Discussion and Analysis of Financial Condition and Results of Operations	27
Item 3.	Quantitative and Qualitative Disclosures about Market Risk	48
Item 4.	Controls and Procedures	49

PART II – OTHER INFORMATION
Item 1.	Legal Proceedings	50
Item 1A.	Risk Factors	50
Item 2.	Unregistered Sales of Equity Securities and Use of Proceeds	50
Item 5.	Other Information	50
Item 6.	Exhibits	51
	Signatures	52

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

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Glossary of Terms

The abbreviations, acronyms and industry terminology used in this report are defined as follows:


ANDX			Andeavor Logistics LLC (formerly known as Andeavor Logistics LP), a wholly-owned subsidiary of the Partnership
ASC			Accounting Standards Codification
ASU			Accounting Standards Update

Barrel			One stock tank barrel, or 42 United States gallons of liquid volume, used in reference to crude oil or other liquid hydrocarbons




DCF (a non-GAAP financial measure)			Distributable Cash Flow

EBITDA (a non-GAAP financial measure)			Earnings Before Interest, Taxes, Depreciation and Amortization


FASB			Financial Accounting Standards Board
FCF (a non-GAAP financial measure)			Free Cash Flow
GAAP			Accounting principles generally accepted in the United States of America



MarkWest			MarkWest Energy Partners, LP., a wholly-owned subsidiary of the Partnership
mbpd			Thousand barrels per day

MMBtu			One million British thermal units, an energy measurement
MMcf/d			One million cubic feet per day
NGL			Natural gas liquids, such as ethane, propane, butanes and natural gasoline





SEC			United States Securities and Exchange Commission
SOFR			Secured Overnight Financing Rate
VIE			Variable interest entity

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PART I—FINANCIAL INFORMATION

Item 1. Financial Statements

MPLX LP

Consolidated Statements of Income (Unaudited)


	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions, except per unit data)	2025		2024		2025		2024
Revenues and other income:
Service revenue	$	750	$	709	$	2,153	$	2,050
Service revenue - related parties	1,094		1,066		3,253		3,102
Service revenue - product related	64		86		233		265
Rental income	68		63		196		187
Rental income - related parties	228		216		655		644
Product sales	525		433		1,510		1,191
Product sales - related parties	26		51		126		164
Sales-type lease revenue	37		34		110		102
Sales-type lease revenue - related parties	113		118		344		359
Income from equity method investments	186		149		542		631
Gain on equity method investments	484		—		484		20
Other income	4		7		19		38
Other income - related parties	40		40		121		117
Total revenues and other income	3,619		2,972		9,746		8,870
Costs and expenses:
Cost of revenues (excludes items below)	395		404		1,153		1,159
Purchased product costs	493		403		1,384		1,148
Rental cost of sales	22		22		61		61
Rental cost of sales - related parties	4		5		12		14
Purchases - related parties	396		402		1,234		1,162
Depreciation and amortization	346		322		996		959
General and administrative expenses	126		107		345		323
Other taxes	36		32		101		99
Total costs and expenses	1,818		1,697		5,286		4,925
Income from operations	1,801		1,275		4,460		3,945
Net interest and other financial costs	243		226		706		692
Income before income taxes	1,558		1,049		3,754		3,253
Provision for income taxes	3		2		5		5
Net income	1,555		1,047		3,749		3,248
Less: Net income attributable to noncontrolling interests	10		10		30		30
Net income attributable to MPLX LP	1,545		1,037		3,719		3,218
Less: Series A preferred unitholders’ interest in net income	—		6		—		21

Limited partners' interest in net income attributable to MPLX LP	$	1,545	$	1,031	$	3,719	$	3,197

Per Unit Data (See Note 7)
Net income attributable to MPLX LP per limited partner unit:
Common - basic	$	1.52	$	1.01	$	3.65	$	3.14
Common - diluted	$	1.52	$	1.01	$	3.65	$	3.14
Weighted average limited partner units outstanding:
Common - basic	1,019		1,020		1,020		1,016
Common - diluted	1,019		1,020		1,020		1,016

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

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MPLX LP

Consolidated Statements of Comprehensive Income (Unaudited)


	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)	2025		2024		2025		2024
Net income	$	1,555	$	1,047	$	3,749	$	3,248
Other comprehensive income, net of tax:
Remeasurements of pension and other postretirement benefits related to equity method investments, net of tax	—		—		8		1
Comprehensive income	1,555		1,047		3,757		3,249
Less comprehensive income attributable to:
Noncontrolling interests	10		10		30		30
Comprehensive income attributable to MPLX LP	$	1,545	$	1,037	$	3,727	$	3,219

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

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MPLX LP

Consolidated Balance Sheets (Unaudited)


(In millions)	September 30, 2025		December 31, 2024
Assets
Cash and cash equivalents	$	1,765	$	1,519

Receivables, less allowance for expected credit loss	729		718
Current assets - related parties	854		830
Inventories	175		180
Assets held for sale	1,034		—
Other current assets	38		29
Total current assets	4,595		3,276
Equity method investments	4,792		4,531
Property, plant and equipment, net	21,348		19,154
Intangibles, net	1,443		518
Goodwill	8,732		7,645
Right of use assets, net	276		273
Noncurrent assets - related parties	983		1,120
Other noncurrent assets	1,058		994
Total assets	43,227		37,511

Liabilities
Accounts payable	131		147
Accrued liabilities	261		295
Current liabilities - related parties	393		396
Accrued property, plant and equipment	400		208

Long-term debt due within one year	1,501		1,693
Accrued interest payable	273		244
Operating lease liabilities	49		45
Liabilities held for sale	230		—
Other current liabilities	264		207
Total current liabilities	3,502		3,235
Long-term deferred revenue	121		317
Long-term liabilities - related parties	339		334
Long-term debt	24,145		19,255
Deferred income taxes	20		18
Long-term operating lease liabilities	220		217
Other long-term liabilities	356		125
Total liabilities	28,703		23,501
Commitments and contingencies (see Note 16)
Series A preferred units ( 0 million and 6 million units outstanding)	—		203

Equity
Common unitholders - public ( 370 million and 370 million units outstanding)	9,513		9,322
Common unitholders - MPC ( 647 million and 647 million units outstanding)	4,778		4,257
Accumulated other comprehensive income (loss)	5		( 3 )
Total MPLX LP partners’ capital	14,296		13,576
Noncontrolling interests	228		231
Total equity	14,524		13,807
Total liabilities, preferred units and equity	$	43,227	$	37,511

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

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MPLX LP

Consolidated Statements of Cash Flows (Unaudited)


	Nine Months Ended September 30,
(In millions)	2025		2024
Operating activities:
Net income	$	3,749	$	3,248
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of deferred financing costs and debt discount	23		41
Depreciation and amortization	996		959
Deferred income taxes	1		—
Gain on equity method investments	( 484 )		( 20 )
(Gain)/loss on disposal of assets	( 1 )		3
Income from equity method investments	( 542 )		( 631 )
Distributions from unconsolidated affiliates	631		596
Change in fair value of derivatives	( 7 )		7
Changes in:
Current receivables	44		138
Inventories	( 19 )		( 11 )
Current liabilities and other current assets	( 38 )		( 54 )
Assets and liabilities - related parties	105		( 23 )

Right of use assets and operating lease liabilities	3		3
Deferred revenue	( 52 )		2
All other, net	4		13
Net cash provided by operating activities	4,413		4,271
Investing activities:
Additions to property, plant and equipment	( 1,094 )		( 748 )
Acquisitions, net of cash acquired	( 3,316 )		( 622 )
Disposal of assets	1		—
Investments - acquisitions and contributions	( 776 )		( 414 )
Investments - redemptions, repayments, return of capital and sales proceeds	143		138
All other, net	108		—
Net cash used in investing activities	( 4,934 )		( 1,646 )
Financing activities:
Long-term debt borrowings	6,541		1,630
Long-term debt repayments	( 2,464 )		( 1 )
Related party debt borrowings	50		—
Related party debt repayments	( 50 )		—
Debt issuance costs	( 62 )		( 15 )
Unit repurchases	( 300 )		( 226 )

Distributions to noncontrolling interests	( 33 )		( 33 )
Distributions to Series A preferred unitholders	( 6 )		( 38 )

Distributions to LP unitholders	( 2,923 )		( 2,585 )
Contributions from MPC	20		26
All other, net	( 6 )		( 5 )
Net cash provided by (used in) financing activities	767		( 1,247 )
Net change in cash, cash equivalents and restricted cash	246		1,378
Cash, cash equivalents and restricted cash at beginning of period	1,519		1,048
Cash, cash equivalents and restricted cash at end of period	$	1,765	$	2,426

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

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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 Income (Loss)		Non-controlling Interests		Total		Series A Preferred Unit-holders
Balance at December 31, 2024	$	9,322	$	4,257	$	( 3 )	$	231	$	13,807	$	203
Net income	410		716		—		10		1,136		—
Unit repurchases	( 100 )		—		—		—		( 100 )		—
Conversion of Series A preferred units	197		—		—		—		197		( 197 )
Distributions	( 353 )		( 619 )		—		( 11 )		( 983 )		( 6 )
Contributions	—		7		—		—		7		—
Other	( 4 )		—		8		—		4		—
Balance at March 31, 2025	$	9,472	$	4,361	$	5	$	230	$	14,068	$	—
Net income	384		664		—		10		1,058		—
Unit repurchases	( 100 )		—		—		—		( 100 )		—
Distributions	( 357 )		( 619 )		—		( 11 )		( 987 )		—
Contributions	—		7		—		—		7		—
Other	3		—		—		—		3		—
Balance at June 30, 2025	$	9,402	$	4,413	$	5	$	229	$	14,049	$	—
Net income	563		982		—		10		1,555		—
Unit repurchases	( 100 )		—		—		—		( 100 )		—
Distributions	( 355 )		( 620 )		—		( 11 )		( 986 )		—
Contributions	—		2		—		—		2		—
Other	3		1		—		—		4		—
Balance at September 30, 2025	$	9,513	$	4,778	$	5	$	228	$	14,524	$	—


	Partnership
	Common Unit-holders Public		Common Unit-holder MPC		Accumulated Other Comprehensive Loss		Non-controlling Interests		Total		Series A Preferred Unit-holders
Balance at December 31, 2023	$	8,700	$	3,758	$	( 4 )	$	235	$	12,689	$	895
Net income	355		640		—		10		1,005		10
Unit repurchases	( 75 )		—		—		—		( 75 )		—
Conversion of Series A preferred units	321		—		—		—		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 income	425		746		—		10		1,181		5
Unit repurchases	( 75 )		—		—		—		( 75 )		—
Conversion of Series A preferred units	354		—		—		—		354		( 354 )
Distributions	( 314 )		( 550 )		—		( 11 )		( 875 )		( 10 )
Contributions	—		8		—		—		8		—
Other	5		—		—		—		5		—
Balance at June 30, 2024	$	9,392	$	4,062	$	( 3 )	$	233	$	13,684	$	202
Net income	377		654		—		10		1,041		6
Unit repurchases	( 76 )		—		—		—		( 76 )		—
Distributions	( 317 )		( 551 )		—		( 11 )		( 879 )		( 5 )
Contributions	—		7		—		—		7		—
Other	2		—		—		—		2		—
Balance at September 30, 2024	$	9,378	$	4,172	$	( 3 )	$	232	$	13,779	$	203

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. 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.

MPLX’s business consists of two segments based upon the product-based value chain each supports. The Crude Oil and Products Logistics segment includes the gathering, transportation, storage and distribution of crude oil, refined products, other hydrocarbon-based products and renewables. The Natural Gas and NGL Services segment gathers, processes and transports natural gas and transports, fractionates, stores and markets 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, 2024. The results of operations for the three and nine months ended September 30, 2025 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.

In the fourth quarter of 2024, we renamed and modified the composition of our segments to better reflect the product-based value chains and growth strategy of MPLX’s operations. Certain prior period financial statement amounts have been reclassified to conform to current period presentation.

2. Accounting Standards

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 in this ASU 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.

3. Acquisitions and Other Transactions

Northwind Midstream Acquisition

On August 29, 2025, MPLX completed the acquisition of 100 percent of Northwind Delaware Holdings LLC (“Northwind Midstream”) for $ 2.4 billion in cash (the “Northwind Midstream Acquisition”). Northwind Midstream provides sour gas gathering and treating services in Lea County, New Mexico, which enhances MPLX’s Permian natural gas and NGL value chain. The

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Northwind Midstream Acquisition was financed with the net proceeds from MPLX's $ 4.5 billion senior notes issued in August 2025.

Northwind Midstream consists of over 200,000 dedicated acres, more than 200 miles of gathering pipelines, two in-service acid gas injection wells at 20 MMcf/d and a third permitted well that will bring its total capacity to 37 MMcf/d. At the time of acquisition, the system had 150 MMcf/d of sour gas treating capacity, with in-process expansion projects expected to increase capacity to over 400 MMcf/d by the second half of 2026. The system is supported by minimum volume commitments by regional producers.

The Northwind Midstream Acquisition was accounted for as a business combination requiring all Northwind Midstream assets and liabilities to be remeasured to fair value. The fair value of property, plant and equipment was based primarily on the cost approach. The fair value of the identifiable intangible assets was primarily based on the multi-period excess earnings method, which is an income approach. The intangible assets acquired are related to various commercial contracts with a weighted average amortization period of 15 years. The following table reflects our preliminary allocation of the $ 2.4 billion purchase price to the Northwind Midstream assets and liabilities:


(In millions)	August 29, 2025
Assets acquired:
Cash and cash equivalents	$	17
Receivables	11
Other current assets	1
Property, plant and equipment	1,182
Intangibles	951
Other noncurrent assets	2
Total assets acquired	2,164
Liabilities assumed:
Accounts payable	15
Accrued property, plant and equipment	84
Accrued liabilities	6
Other current liabilities	1
Long-term operating lease liabilities	1
Total liabilities assumed	107
Total identifiable net assets	2,057
Goodwill	356
Fair value of net assets acquired	$	2,413

The allocation is subject to revision, as certain data necessary to complete the purchase price allocation is not yet available, including, but not limited to, the final valuation of property, plant and equipment and intangible assets acquired, which may impact the amount of goodwill recognized. The final valuation will be completed no later than one year from the acquisition date. The results for the acquired business are reported within our Natural Gas and NGL Services segment.

The purchase price allocation resulted in the recognition of $ 356 million in goodwill by our Natural Gas and NGL Services segment, all of which is deductible for tax purposes. Goodwill represents the accelerated growth opportunities in the Permian using Northwind Midstream's asset base, which is complementary and adjacent to MPLX's existing Delaware basin natural gas system and offers optionality to direct volumes through our integrated system.

Pro forma financial information assuming the Northwind Midstream Acquisition had occurred as of the beginning of the calendar year prior to the year of the acquisition, as well as the revenues and earnings generated during the period since the acquisition date, were not material for disclosure purposes.

Announced Divestiture of Rockies Operations

On August 26, 2025, MPLX entered into a definitive agreement to divest its Rockies gathering and processing operations (the “Rockies”) to a subsidiary of Harvest Midstream (“Harvest”) for $ 1.0 billion in cash, subject to customary purchase price adjustments.

The assets and liabilities to be sold as part of this transaction are shown on the Consolidated Balance Sheet as Assets held for sale and Liabilities held for sale, respectively, as of September 30, 2025. Upon classification as held for sale, depreciation and amortization of the assets ceased. Since the sale of these assets does not represent a strategic shift that has or will have a material effect on our operations or financial results, the planned divestiture is not considered to be a discontinued operation. The Rockies operations are currently reported within the Natural Gas and NGL Services segment.

The transaction is expected to close in the fourth quarter of 2025, subject to customary closing conditions, and is expected to result in an estimated gain in excess of $ 150 million upon closing.

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The following table presents the carrying value of assets and liabilities as presented within assets and liabilities held for sale on our Consolidated Balance Sheets as of September 30, 2025:


(In millions)	September 30, 2025
Assets
Receivables, less allowance for expected credit loss	$	28

Inventories	25
Equity method investments	123
Property, plant and equipment, net of accumulated depreciation of $ 340	788
Intangibles, net of accumulated amortization of $ 178	68
Right of use assets, net	2

Total assets classified as held for sale	1,034

Liabilities
Accounts payable	20
Accrued liabilities	7

Operating lease liabilities	1
Other current liabilities	19
Long-term deferred revenue	182

Other long-term liabilities	1
Total liabilities classified as held for sale	$	230

BANGL, LLC Acquisitions

BANGL, LLC (“BANGL”) owns and operates an NGL pipeline system that connects production in the Delaware and Midland basins to key demand centers along the Gulf Coast. On July 31, 2024, MPLX exercised its right of first offer under the BANGL joint venture agreement to purchase an additional 20 percent ownership interest in BANGL for $ 210 million in cash, which increased total ownership interest to 45 percent (the “2024 BANGL Transaction”). The purchase price of the additional 20 percent ownership interest in BANGL exceeded our portion of the underlying net assets of the joint venture by approximately $ 156 million. Following the 2024 BANGL Transaction, our investment in BANGL continued to be accounted for as an equity method investment.

On July 1, 2025, MPLX purchased the remaining 55 percent interest in BANGL for $ 703 million in cash, plus an earnout provision of up to $ 275 million based on targeted EBITDA growth from 2026 to 2029 (the “BANGL Acquisition”). We recorded a liability for these contingent payments in the third quarter of 2025. See Note 10 for additional details on the inputs used to measure the fair value of these contingent payments. On July 3, 2025, MPLX used cash on hand to extinguish approximately $ 656 million principal amount of debt outstanding, including interest, related to certain term and revolving loans assumed as part of the BANGL Acquisition (the “BANGL Debt Repayment”).

Upon acquisition of the remaining 55 percent interest in BANGL, our existing equity investment was remeasured to fair value resulting in the recognition of a $ 484 million gain, which is included in Gain on equity method investments within the accompanying Consolidated Statements of Income. The fair value of the previously held equity method investment was estimated using an income approach, with significant valuation inputs including forecasted cash flows and discount rates ranging from 11 to 12 percent . As a result of the BANGL Acquisition, we now own 100 percent of BANGL and its results are reflected in our Natural Gas and NGL Services segment within our consolidated financial results.

The following table summarizes the purchase price consideration in connection with the BANGL Acquisition:


Total cash paid	$	703
Fair value of contingent consideration as of acquisition date	234
Total consideration	937
Fair value of previously held equity interest	766
Fair value of net assets acquired	$	1,703

The BANGL Acquisition was accounted for as a business combination requiring all BANGL assets and liabilities to be remeasured to fair value. The fair value of property, plant and equipment was determined using a combination of both the cost and income approach. The fair value of the identifiable intangible assets was primarily based on the multi-period excess earnings

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method, which is an income approach. The intangible asset acquired is related to a customer relationship with an amortization period of 11 years. The following table reflects our preliminary determination of the fair value of the BANGL assets and liabilities:


(In millions)	July 1, 2025
Assets acquired:
Cash and cash equivalents	$	18
Other current assets	4
Property, plant and equipment	1,550
Intangibles	77
Other noncurrent assets	22
Total assets acquired	1,671
Liabilities assumed:
Long-term debt due within one year	46
Other current liabilities	42
Long-term debt	610
Other long-term liabilities	1
Total liabilities assumed	699
Total identifiable net assets	972
Goodwill	731
Fair value of net assets acquired	$	1,703

The purchase price allocation resulted in the recognition of $ 731 million in goodwill by our Natural Gas and NGL Services segment, 55 percent of which is deductible for tax purposes. Goodwill represents the advancement of our wellhead-to-water strategy by securing full ownership of a strategically located NGL transport asset which further integrates our midstream infrastructure connecting the Permian and Gulf Coast regions.

Pro forma financial information assuming the BANGL Acquisition had occurred as of the beginning of the calendar year prior to the year of the acquisition, as well as the revenues and earnings generated during the period since the acquisition date, were not material for disclosure purposes.

Matterhorn Express Pipeline Acquisition

On June 16, 2025, MPLX purchased an additional five percent ownership interest in the joint venture that owns and operates the Matterhorn Express pipeline for $ 151 million, bringing our total interest to 10 percent. The pipeline is designed to transport natural gas from the Permian basin to the Katy area near Houston. The purchase price of the additional five percent ownership interest in the joint venture exceeded the amount of the claim to the underlying net assets of the joint venture by approximately $ 124 million, with $ 63 million of this difference attributed to property, plant and equipment and $ 61 million attributed to customer-related intangibles. The amounts attributed to property, plant and equipment and customer-related intangibles will be amortized to net income over the remaining useful lives of the assets and the weighted average remaining term of the customer contracts, respectively. Our investment in the joint venture that owns and operates the Matterhorn Express pipeline continues to be accounted for as an equity method investment within our Natural Gas and NGL Services segment.

Whiptail Midstream Acquisition

On March 11, 2025, MPLX acquired gathering businesses from Whiptail Midstream, LLC for $ 237 million in cash. These San Juan basin assets consist primarily of crude and natural gas gathering systems in the Four Corners region, and enhance our strategic relationship with MPC. The acquisition was accounted for as a business combination, which requires all the identifiable assets acquired and liabilities assumed to be remeasured to fair value at the date of acquisition. The preliminary determination of the fair value includes $ 172 million of property, plant and equipment, $ 41 million of intangibles and $ 24 million of net working capital. The allocation is subject to revision, as certain data necessary to complete the purchase price allocation is not yet available, including, but not limited to, the final valuation of assets acquired and liabilities assumed. The final valuation will be completed no later than one year from the acquisition date. The results for the acquired business are allocated between our two segments based on the product-based value chain the underlying assets support.

Whistler Joint Venture Transaction

On May 29, 2024, MPLX and its joint venture partner contributed their respective membership interests 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 (collectively, the “Whistler Joint Venture Transaction”). As a result of the transaction, MPLX’s voting interest in the joint venture was reduced from 37.5 percent to 30.4

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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 to purchase additional ownership interests 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”). After giving effect to the acquisition, MPLX owns a combined direct and indirect 73 percent interest in OGC and a 100 percent interest in OCC. In addition, MPLX acquired 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 $ 75 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 Natural Gas and NGL Services 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 $ 507 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 Gain on equity method investments within the accompanying Consolidated Statements of Income. The fair value of equity method investments was based on a discounted cash flow model.

4. Equity Method Investments

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


		Ownership as of	Carrying value at
		September 30,	September 30,		December 31,
(In millions, except ownership percentages)	VIE	2025	2025		2024
Crude Oil and Products Logistics
Illinois Extension Pipeline Company, L.L.C.		35 %	$	219	$	218
LOOP LLC		41 %	314		310
MarEn Bakken Company LLC (1)		25 %	508		526
Other (2)	X		551		541
Total Crude Oil and Products Logistics			1,592		1,595
Natural Gas and NGL Services
BANGL, LLC (3)		100 %	—		281
MarkWest EMG Jefferson Dry Gas Gathering Company, L.L.C. (4)	X	67 %	410		329
MarkWest Utica EMG, L.L.C.	X	60 %	836		742
Ohio Gathering Company L.L.C. (5)	X	33 %	451		470
Sherwood Midstream LLC	X	50 %	479		488
WPC Parent, LLC		30 %	389		208
Other (2)	X		758		418
Total Natural Gas and NGL Services			3,323		2,936
Total			$	4,915	$	4,531

(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, the “Bakken Pipeline system”).

(2) Included within Other are certain equity method investments that have been deemed to be VIEs, as well as $ 123 million in investments classified as held for sale as part of the Rockies operations divestiture discussed in Note 3.

(3) At December 31, 2024, we owned a 45 percent interest in BANGL. On July 1, 2025, we acquired the remaining 55 percent interest in BANGL. As a result of acquiring the remaining interest, we obtained control of and now consolidate BANGL.

(4) On March 31, 2025, MPLX contributed a 100 percent owned subsidiary with a fair value of $ 125 million to MarkWest EMG Jefferson Dry Gas Gathering Company, L.L.C. As a result of the transaction, MPLX received special distributions of $ 21 million in the first quarter of 2025 and $ 21 million in the third quarter of 2025, which are reflected as a return of capital on the Consolidated Statement of Cash Flows.

(5) MPLX also holds a 40 percent indirect interest in OGC through our ownership interest in MarkWest Utica EMG, L.L.C.

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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, 2025 and September 30, 2024. 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. In addition, MPLX has obligations to MPC for services provided to MPLX by MPC under omnibus and employee services agreements as well as various other agreements. MPLX also had a keep-whole commodity agreement with MPC under which MPC paid us a processing fee for NGLs related to keep-whole agreements and we paid MPC a marketing fee in exchange for assuming the commodity risk. This agreement expired in March 2025.

Related Party Loan

MPLX is party to a loan agreement (the “MPC Loan Agreement”) with MPC. Under the terms of the MPC Loan Agreement, MPC extends loans to MPLX on a revolving basis as requested by MPLX and as agreed to by MPC. The borrowing capacity of the MPC Loan Agreement is $ 1.5 billion aggregate principal amount of all loans outstanding at any one time. The MPC Loan Agreement is scheduled to expire, and borrowings under the loan agreement are scheduled to mature and become due and payable, on July 31, 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.

Activity on the MPC Loan Agreement for the nine months ended September 30, 2025 is summarized in the table below. There was no activity on the MPC Loan Agreement for the nine months ended September 30, 2024.


	Nine Months Ended September 30,
(In millions, except %)	2025
Borrowings	$	50
Weighted average interest rate of borrowings	5.68		%
Repayments	$	50
Outstanding balance at end of period	$	—

Related Party Revenue and Other Income

Related party revenue consists primarily of revenue recognized from commercial agreements with MPC as well as fees charged under operating agreements with MPC and our equity affiliates as discussed above.

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, 2025, these sales totaled $ 151 million and $ 476 million, respectively. For the three and nine months ended September 30, 2024, these sales totaled $ 177 million and $ 561 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”), for certain employee services provided to MPLX under employee services agreements (“ESA charges”) and fees paid under co-location agreements and ground lease agreements.

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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. Additionally, we incur costs under agreements for transportation and processing services with certain of our unconsolidated affiliates.

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, 2025, General and administrative expenses incurred from MPC totaled $ 80 million and $ 236 million, respectively. For the three and nine months ended September 30, 2024, General and administrative expenses incurred from MPC totaled $ 73 million and $ 217 million, respectively.

Some charges incurred under the omnibus and employee service agreements are related to engineering services and are associated with assets under construction. These charges are added to Property, plant and equipment, net on the Consolidated Balance Sheets. For the three and nine months ended September 30, 2025, these charges totaled $ 64 million and $ 159 million, respectively. For the three and nine months ended September 30, 2024, these charges totaled $ 44 million and $ 124 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.


(In millions)	September 30, 2025		December 31, 2024
Current assets - related parties
Receivables	$	592	$	620
Lease receivables	247		204
Prepaid	13		5
Other	2		1
Total	854		830
Noncurrent assets - related parties
Long-term lease receivables	483		677
Right of use assets	223		226
Unguaranteed residual asset	241		189
Long-term receivables	36		28
Total	983		1,120
Current liabilities - related parties
MPC Loan Agreement and other payables (1)	274		288
Deferred revenue	118		106
Operating lease liabilities	1		2
Total	393		396
Long-term liabilities - related parties
Long-term operating lease liabilities	222		224
Long-term deferred revenue	117		110
Total	$	339	$	334

(1) There were no borrowings outstanding on the MPC Loan Agreement as of September 30, 2025 or December 31, 2024.

6. Equity

The changes in the number of common units during the nine months ended September 30, 2025 are summarized below:


(In units)			Common Units
Balance at December 31, 2024			1,017,142,290
Unit-based compensation awards			147,670
Conversion of Series A preferred units			6,166,965
Units redeemed in unit repurchase programs			( 5,858,943 )
Balance at September 30, 2025			1,017,597,982

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Unit Repurchase Program

On August 5, 2025, we announced a board authorization for the repurchase of $ 1.0 billion of MPLX common units held by the public in addition to the $ 1.0 billion common unit repurchase authorization announced on August 2, 2022. These unit repurchase authorizations have 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)	2025		2024		2025		2024
Number of common units repurchased	2		2		6		5
Cash paid for common units repurchased (1)	$	100	$	76	$	300	$	226
Average cost per unit (1)	$	50.86	$	42.89	$	51.20	$	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, 2025, we had $ 1.2 billion remaining under the unit repurchase authorizations.

Series A Redeemable Preferred Unit Conversions

On February 11, 2025, MPLX exercised its right to convert the remaining 6 million outstanding Series A preferred units into common units in accordance with the conversion provision outlined in our Sixth Amended and Restated Agreement of Limited Partnership.

Distributions

Quarterly distributions for 2025 and 2024 are summarized below:


(Per common unit)	2025		2024
March 31,	$	0.9565	$	0.8500
June 30,	0.9565		0.8500
September 30,	1.0765		0.9565

The allocation of total quarterly cash distributions to common and preferred unitholders is as follows for the three and nine months ended September 30, 2025 and September 30, 2024. Distributions are not accrued until declared. MPLX’s distributions are declared for the prior quarter subsequent to the quarter end; therefore, the following table represents total cash distributions applicable to the period for which the distributions relate as opposed to the quarter in which they were declared and paid.


	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)	2025		2024		2025		2024
Common and preferred unit distributions:
Common unitholders, includes common units of general partner	$	1,095	$	974	$	3,046	$	2,706
Series A preferred unit distributions	—		6		—		21

Total cash distributions declared	$	1,095	$	980	$	3,046	$	2,727

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, 2025 and September 30, 2024, MPLX had participating securities consisting of common units, certain equity-based compensation awards and Series A preferred units, and also had dilutive potential common units consisting of certain equity-based compensation awards. Potential common units that were anti-dilutive, and therefore omitted from the diluted earnings per unit calculation for the three and nine months ended September 30, 2025 and September 30, 2024, were less than one million .

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	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions, except per unit data)	2025		2024		2025		2024
Net income attributable to MPLX LP (1) :	$	1,545	$	1,037	$	3,719	$	3,218
Less: Distributions declared on Series A preferred units	—		6		—		21

Distributed and undistributed earnings allocated to other participating securities	1		—		2		7

Net Income available to common unitholders	$	1,544	$	1,031	$	3,717	$	3,190
Weighted average units outstanding:
Basic	1,019		1,020		1,020		1,016
Diluted	1,019		1,020		1,020		1,016
Net income attributable to MPLX LP per limited partner unit:
Basic	$	1.52	$	1.01	$	3.65	$	3.14
Diluted	$	1.52	$	1.01	$	3.65	$	3.14

(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 product-based value chain basis. MPLX has two reportable segments: Crude Oil and Products Logistics and Natural Gas and NGL Services. Each of these segments is organized and managed based upon the product-based value chain each supports.

• Crude Oil and Products Logistics – 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.

• Natural Gas and NGL Services – gathers, processes and transports natural gas; and transports, fractionates, stores and markets NGLs.

The CODM evaluates the performance of our segments using Segment Adjusted EBITDA. The CODM uses Segment Adjusted EBITDA results when making decisions about allocating capital and personnel as a part of the annual business plan process and ongoing monitoring of performance. 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; (vii) transaction-related costs and (viii) other adjustments, as applicable. These items are either: (i) believed to be non-recurring in nature; (ii) not believed to be allocable or controlled by the segment; or (iii) are not tied to the operational performance of the segment. Assets by segment are not a measure used to assess the performance of the Partnership by our CODM and thus are not reported in our disclosures.

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The tables below present information about our reportable segments:


	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)	2025		2024		2025		2024
Crude Oil and Products Logistics
Service revenue	$	1,205	$	1,158	$	3,569	$	3,367
Rental income	239		223		682		666
Product related revenue	4		5		12		14
Sales-type lease revenue	113		118		344		359
Income from equity method investments	71		70		186		213
Other income	28		33		94		113
Total segment revenues and other income (1)	1,660		1,607		4,887		4,732
Operating expenses	553		542		1,613		1,557
Other segment items (2)	( 30 )		( 29 )		( 98 )		( 77 )
Segment Adjusted EBITDA (3)	1,137		1,094		3,372		3,252
Capital expenditures	147		112		391		299
Investments in unconsolidated affiliates (4)	13		1		13		93
Natural Gas and NGL Services
Service revenue	639		617		1,837		1,785
Rental income	57		56		169		165
Product related revenue	611		565		1,857		1,606
Sales-type lease revenue	37		34		110		102
Income from equity method investments	115		79		356		418
Gain on equity method investments (5)	484		—		484		20
Other income	16		14		46		42
Total segment revenues and other income (1)	1,959		1,365		4,859		4,138
Purchased product costs	493		403		1,384		1,148
Operating expenses	426		430		1,293		1,261
Other segment items (2)	411		( 88 )		341		( 21 )
Segment Adjusted EBITDA (3)	629		620		1,841		1,750
Capital expenditures	447		189		812		421
Investments in unconsolidated affiliates (4)	$	227	$	31	$	549	$	93

(1) Within the total segment revenues and other income amounts presented above, third-party revenues for the Crude Oil and Products Logistics segment were $ 201 million and $ 565 million for the three and nine months ended September 30, 2025, respectively, and $ 186 million and $ 563 million for the three and nine months ended September 30, 2024, respectively. Third-party revenues for the Natural Gas and NGL Services segment were $ 1,917 million and $ 4,682 million for the three and nine months ended September 30, 2025, respectively, and $ 1,295 million and $ 3,921 million for the three and nine months ended September 30, 2024, respectively.

(2) Other segment items in the Crude Oil and Products Logistics segment include income from equity method investments, distributions and adjustments related to equity method investments, equity-based compensation and other miscellaneous items. Other segment items in the Natural Gas and NGL Services segment include income from and gain on equity method investments, distributions and adjustments related to equity method investments, transaction-related costs, unrealized derivative gain/loss and other miscellaneous items.

(3) See below for the reconciliation from Segment Adjusted EBITDA to Net income.

(4) Investments in unconsolidated affiliates in the Crude Oil and Products Logistics segment for 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. Investments in unconsolidated affiliates for the three and nine months ended September 30, 2024 exclude $ 18 million related to acquisition of an additional interest in Wink to Webster Pipeline LLC. Investments in unconsolidated affiliates in the Natural Gas and NGL Services segment for the three and nine months ended September 30, 2025 includes cash contributions to several joint ventures to fund current growth capital projects. Investments in unconsolidated affiliates for the nine months ended September 30, 2025 exclude $ 151 million related to the acquisition of an additional interest in the joint venture that owns and operates the Matterhorn Express Pipeline, and the three and nine months ended September 30, 2025 exclude a $ 49 million capital contribution to WPC Parent, LLC to purchase Enbridge’s special membership interest in the Rio Bravo Pipeline project and a $ 13 million payment related to earnout associated with MXP Parent, LLC. Investments in unconsolidated affiliates for the three and nine months ended September 30, 2024 exclude $ 210 million related to the 2024 BANGL Transaction.

(5) The three and nine months ended September 30, 2025 represent the gain on remeasurement of our existing equity investment in BANGL in conjunction with the BANGL Acquisition. The nine months ended September 30, 2024 represents the gain on remeasurement of our existing equity investment in OCC in conjunction with the Utica Midstream Acquisition.

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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)	2025		2024		2025		2024
Reconciliation to Net income:
Crude Oil and Products Logistics Segment Adjusted EBITDA	$	1,137	$	1,094	$	3,372	$	3,252
Natural Gas and NGL Services Segment Adjusted EBITDA	629		620		1,841		1,750
Total reportable segments	1,766		1,714		5,213		5,002
Depreciation and amortization (1)	( 346 )		( 322 )		( 996 )		( 959 )
Gain on equity method investments	484		—		484		—
Net interest and other financial costs	( 243 )		( 226 )		( 706 )		( 692 )
Income from equity method investments	186		149		542		631
Distributions/adjustments related to equity method investments	( 251 )		( 253 )		( 707 )		( 671 )
Transaction-related costs (2)	( 21 )		—		( 21 )		—
Adjusted EBITDA attributable to noncontrolling interests	11		11		33		33
Other (3)	( 31 )		( 26 )		( 93 )		( 96 )
Net income	$	1,555	$	1,047	$	3,749	$	3,248

(1) Depreciation and amortization attributable to Crude Oil and Products Logistics was $ 139 million and $ 407 million for the three and nine months ended September 30, 2025, respectively, and $ 132 million and $ 393 million for the three and nine months ended September 30, 2024, respectively. Depreciation and amortization attributable to Natural Gas and NGL Services was $ 207 million and $ 589 million for the three and nine months ended September 30, 2025, respectively, and $ 190 million and $ 566 million for the three and nine months ended September 30, 2024, respectively.

(2) Transaction-related costs include costs associated with acquisition and divestiture-related activities, including significant transactions discussed in Note 3.

(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, 2025						December 31, 2024
(In millions)	Gross PP&E		Accumulated Depreciation		Net PP&E		Gross PP&E		Accumulated Depreciation		Net PP&E
Crude Oil and Products Logistics	$	13,684	$	4,928	$	8,756	$	13,189	$	4,542	$	8,647
Natural Gas and NGL Services	17,436		4,844		12,592		15,215		4,708		10,507
Total	$	31,120	$	9,772	$	21,348	$	28,404	$	9,250	$	19,154

10. Fair Value Measurements

Fair Values – Recurring

The following table presents the impact on the Consolidated Balance Sheets of MPLX’s Level 3 instruments carried at fair value on a recurring basis as of September 30, 2025 and December 31, 2024 by fair value hierarchy level.


	September 30, 2025				December 31, 2024
(In millions)	Asset		Liability		Asset		Liability


Embedded derivatives in commodity contracts:
Other current assets / Other current liabilities	$	—	$	8	$	—	$	10
Other noncurrent assets / Other long-term liabilities	—		43		—		48
Total embedded derivatives in commodity contracts	—		51		—		58
Contingent consideration / Other long-term liabilities	—		234		—		—
Total carrying value in Consolidated Balance Sheets	$	—	$	285	$	—	$	58

Level 3 instruments include a liability for contingent consideration related to the BANGL Acquisition earnout provision and an embedded derivative liability for a natural gas purchase commitment embedded in a keep-whole processing agreement.

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The fair value calculation for the contingent consideration liability was estimated using discounted cash flows based on a Monte Carlo simulation. Future earnout payments are tied to the achievement of EBITDA growth from 2026 to 2029, which includes the significant unobservable input of forecasted throughput volumes. The earnout payment will continue to be remeasured at fair value each quarter with changes in fair value recognized in earnings until either the EBITDA targets are met or the earnout period ends, with the total payout capped at $ 275 million.

The fair value calculation for the embedded derivative liability for the natural gas purchase commitment used significant unobservable inputs including: (1) NGL prices interpolated and extrapolated due to inactive markets ranging from $ 0.66 to $ 1.30 per gallon with a weighted average of $ 0.79 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)	2025		2024		2025		2024

Beginning balance	$	( 55 )	$	( 69 )	$	( 58 )	$	( 61 )
Contingent consideration (1)	( 234 )		—		( 234 )		—
Unrealized and realized gain/(loss) included in Net Income (2)	2		( 3 )		( 1 )		( 18 )
Settlements	2		3		8		10

Ending balance	$	( 285 )	$	( 69 )	$	( 285 )	$	( 69 )

The amount of total loss for the period included in earnings attributable to the change in unrealized gain/(loss) relating to liabilities still held at end of period	$	2	$	( 3 )	$	( 1 )	$	( 15 )

(1) Liability recorded in the third quarter of 2025 related to the BANGL Acquisition earnout provision.

(2) Gain/(loss) on derivatives embedded in commodity contracts are recorded in Purchased product costs in the Consolidated Statements of Income.

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, historical incurrence of credit losses, and expected insignificance of future credit losses, 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, 2025				December 31, 2024
(In millions)	Fair Value		Carrying Value		Fair Value		Carrying Value
Outstanding debt (1)	$	24,890	$	25,818	$	19,574	$	21,068

(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

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 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

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of Income. For further information regarding the fair value measurement of derivative instruments, see Note 10. As of September 30, 2025 and December 31, 2024, the estimated fair value of this contract was a liability of $ 51 million and $ 58 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, 2025 and December 31, 2024, 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)	2025		2024		2025		2024
Product sales
Realized gain	$	—	$	1	$	—	$	1
Unrealized gain	—		3		—		1
Product sales derivative gain/(loss)	—		4		—		2
Purchased product costs
Realized loss	( 2 )		( 3 )		( 8 )		( 10 )
Unrealized gain/(loss)	4		—		7		( 8 )
Purchased product cost derivative gain/(loss)	2		( 3 )		( 1 )		( 18 )





Total derivative gain/(loss) included in Net income	$	2	$	1	$	( 1 )	$	( 16 )

12. Debt

MPLX’s outstanding borrowings consist of the following:


(In millions)	September 30, 2025		December 31, 2024
MPLX LP:
MPLX Credit Agreement	$	—	$	—

































Fixed rate senior notes	25,969		21,158
Consolidated subsidiaries:
MarkWest	—		11
ANDX	31		31
Finance lease obligations	7		6
Total	26,007		21,206
Unamortized debt issuance costs	( 179 )		( 126 )
Unamortized discount	( 182 )		( 132 )
Amounts due within one year	( 1,501 )		( 1,693 )
Total long-term debt due after one year	$	24,145	$	19,255

Credit Agreement

MPLX’s credit agreement (the “MPLX Credit Agreement”) matures in July 2027 and, among other things, provides for a $ 2.0 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 $ 2.0 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.

During the nine months ended September 30, 2025, MPLX borrowed $ 106 million under the MPLX Credit Agreement, at a weighted average interest rate of 7.740 percent, and repaid $ 106 million of these borrowings. At September 30, 2025, MPLX had no outstanding borrowings and less than $ 1 million in letters of credit outstanding under this facility, resulting in total availability of approximately $ 2.0 billion or approximately 100 percent of the borrowing capacity.

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Fixed Rate Senior Notes

MPLX’s senior notes, including those issued by consolidated subsidiaries, consist of various series of senior notes maturing between 2026 and 2058 with interest rates ranging from 1.750 percent to 6.200 percent. Interest on each series of notes is payable semi-annually in arrears on various dates depending on the series of the notes.

The following table summarizes debt issuances during the nine months ended September 30, 2025, all of which were issued in an underwritten public offering:


Issue Date	Aggregate Principal Amount (in millions)		Note(s)	Coupon (percent)	Price to Public (percent of par)	Interest Payment Dates	Maturity Date
March 10, 2025	$	1,000	(1)	5.400	99.398	April 1 and October 1	April 1, 2035
March 10, 2025	1,000		(1)	5.950	98.331	April 1 and October 1	April 1, 2055
August 11, 2025	1,250		(2)	4.800	99.880	February 15 and August 15	February 15, 2031
August 11, 2025	750		(2)	5.000	98.936	January 15 and July 15	January 15, 2033
August 11, 2025	1,500		(2)	5.400	98.943	March 15 and September 15	September 15, 2035
August 11, 2025	$	1,000	(2)	6.200	98.277	March 15 and September 15	September 15, 2055

(1) On April 9, 2025, MPLX used $ 1.2 billion of the net proceeds from the issuance of senior notes in March 2025 to redeem all of (i) MPLX’s outstanding $ 1,189 million aggregate principal amount of 4.875 percent senior notes due June 2025 and (ii) MarkWest’s outstanding $ 11 million aggregate principal amount of 4.875 percent senior notes due June 2025. MPLX intends to use the remaining net proceeds for general partnership purposes.

(2) We used a portion of the net proceeds from this offering to fund the Northwind Midstream Acquisition, including the payment of related fees and expenses, and to increase cash and cash equivalents following the recently completed BANGL Acquisition and BANGL Debt Repayment. We intend to use the remainder of the net proceeds from this offering for general partnership purposes, which may include capital expenditures and other working capital requirements.

On February 18, 2025, MPLX repaid all of MPLX’s outstanding $ 500 million aggregate principal amount of 4.000 percent senior notes due February 2025 at maturity.

On July 3, 2025, MPLX used cash on hand to extinguish approximately $ 656 million principal amount of debt outstanding, including interest, related to certain term and revolving loans assumed as part of the BANGL Acquisition. See Note 3 for additional information on the BANGL Acquisition.

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)	2025		2024		2025		2024
Interest expense	$	279	$	251	$	767	$	717
Other financial costs	( 9 )		15		14		57
Interest income	( 16 )		( 35 )		( 50 )		( 68 )
Capitalized interest	( 11 )		( 5 )		( 25 )		( 14 )

Net interest and other financial costs	$	243	$	226	$	706	$	692

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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, 2025 and September 30, 2024:


	Three Months Ended September 30, 2025
(In millions)	Crude Oil and Products Logistics		Natural Gas and NGL Services		Total
Revenues and other income:
Service revenue	$	115	$	635	$	750
Service revenue - related parties	1,090		4		1,094
Service revenue - product related	—		64		64
Product sales	1		524		525
Product sales - related parties	3		23		26
Total revenues from contracts with customers	$	1,209	$	1,250	2,459
Non-ASC 606 revenue (1)					1,160
Total revenues and other income					$	3,619


	Three Months Ended September 30, 2024
(In millions)	Crude Oil and Products Logistics		Natural Gas and NGL Services		Total
Revenues and other income:
Service revenue	$	101	$	608	$	709
Service revenue - related parties	1,057		9		1,066
Service revenue - product related	—		86		86
Product sales	1		432		433
Product sales - related parties	4		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


	Nine Months Ended September 30, 2025
(In millions)	Crude Oil and Products Logistics		Natural Gas and NGL Services		Total
Revenues and other income:
Service revenue	$	332	$	1,821	$	2,153
Service revenue - related parties	3,237		16		3,253
Service revenue - product related	—		233		233
Product sales	3		1,507		1,510
Product sales - related parties	9		117		126
Total revenues from contracts with customers	$	3,581	$	3,694	7,275
Non-ASC 606 revenue (1)					2,471
Total revenues and other income					$	9,746

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	Nine Months Ended September 30, 2024
(In millions)	Crude Oil and Products Logistics		Natural Gas and NGL Services		Total
Revenues and other income:
Service revenue	$	286	$	1,764	$	2,050
Service revenue - related parties	3,081		21		3,102
Service revenue - product related	—		265		265
Product sales	4		1,187		1,191
Product sales - related parties	10		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

(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 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 contracts, we receive payments in advance of satisfying our performance obligations, which are recorded as contract liabilities. Contract liabilities, which are presented 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. Breakage related to minimum volume commitments 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.

The tables below reflect the changes in ASC 606 contract balances for the nine months ended September 30, 2025 and September 30, 2024:


(In millions)	Balance at December 31, 2024		Additions/ (Deletions)		Revenue Recognized (1)		Balance at September 30, 2025
Contract assets	$	2	$	10	$	—	$	12
Long-term contract assets	—		4		—		4
Deferred revenue	84		22		( 59 )		47
Deferred revenue - related parties	71		66		( 62 )		75
Long-term deferred revenue	315		( 15 )		—		300
Long-term deferred revenue - related parties	$	44	$	1	$	—	$	45


(In millions)	Balance at December 31, 2023		Additions/ (Deletions)		Revenue Recognized (1)		Balance at September 30, 2024
Contract assets	$	3	$	—	$	( 1 )	$	2
Long-term contract assets	1		( 1 )		—		—
Deferred revenue	59		65		( 42 )		82
Deferred revenue - related parties	47		56		( 50 )		53
Long-term deferred revenue	344		( 22 )		—		322
Long-term deferred revenue - related parties	$	29	$	5	$	—	$	34

(1) No significant revenue was recognized related to past performance obligations in the current periods.

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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, 2025. 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)
2025	$	0.6
2026	2.0
2027	1.8
2028	0.7
2029	0.3
2030 and thereafter	1.0
Total estimated revenue on remaining performance obligations	$	6.4

As of September 30, 2025, unsatisfied performance obligations included in the Consolidated Balance Sheets are $ 467 million and will be recognized as revenue as the obligations are satisfied, which is generally expected to occur over the next 19 years. A portion of this amount is not disclosed in the table above as it is deemed variable consideration due to volume variability.

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15. Supplemental Cash Flow Information


	Nine Months Ended September 30,
(In millions)	2025		2024
Net cash provided by operating activities included:
Interest paid (net of amounts capitalized)	$	705	$	724
Income taxes paid	3		2
Cash paid for amounts included in the measurement of lease liabilities:
Payments on operating leases	47		53

Net cash provided by financing activities included:
Principal payments under finance lease obligations	2		1
Non-cash investing and financing activities:

Transfers of property, plant and equipment to lease receivable	123		108
Contribution of assets (1)	115		—

ROU assets obtained in exchange for new operating lease obligations	30		34
ROU assets obtained in exchange for new finance lease obligations	3		—
Book value of equity method investment (2)	282		—
Contingent consideration (3)	$	234	$	—

(1) Represents the book value of assets contributed by MPLX to a joint venture.

(2) Represents the book value of MPLX’s equity method investment in BANGL, prior to MPLX buying out the remaining interest in the entity. See Note 3 - BANGL, LLC Acquisitions.

(3) See Note 3 - BANGL, LLC Acquisitions.

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)	2025		2024
Additions to property, plant and equipment	$	1,094	$	748
Increase/(Decrease) in capital accruals	131		( 28 )
Other	( 22 )		—
Total capital expenditures	$	1,203	$	720

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 $ 14 million and $ 15 million at September 30, 2025 and December 31, 2024, respectively. 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

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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 seek disgorgement of pipeline profits from June 1, 2013 to present, removal of the pipeline 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

Dakota Access

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, 2025, 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 a $ 109 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 Natural Gas and NGL Services segment. Certain natural gas processing and gathering arrangements require MPLX to construct new 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, 2025, 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.

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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, 2024.

Disclosures Regarding Forward-Looking Statements

This Quarterly Report on Form 10-Q, particularly Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations and Item 3. 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,” “focus,” “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, 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 the federal government shutdown, tariffs, inflation, interest rates, changes in governmental policies relating to refined petroleum products, crude oil, natural gas, NGLs, renewable diesel and other renewable fuels or taxation, including changes in tax regulations or guidance promulgated pursuant to the new legislation implemented in the One Big Beautiful Bill Act;

• 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, if at all, 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, renewable diesel and other renewable fuels 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 renewable diesel and other renewable fuels;

• 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, tariffs, 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 capital investments;

• the financing and distribution decisions of joint ventures we do not control;

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• the availability of desirable strategic alternatives to optimize portfolio assets and our ability to obtain regulatory and other approvals with respect thereto, including MPLX’s ability to successfully divest its Rockies gathering and processing operations (the “Rockies”);

• completion of midstream infrastructure by competitors;

• 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;

• the establishment or increase of tariffs on goods, including crude oil and other feedstocks imported into the United States, other trade protection measures or restrictions or retaliatory actions from foreign governments;

• changes in producer customers’ drilling plans or in volumes of throughput of crude oil, natural gas, NGLs, refined products, other hydrocarbon-based products or renewable diesel and other renewable fuels;

• 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 renewable diesel and other renewable fuels;

• 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 renewable diesel and other renewable fuels;

• 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;

• 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 renewable diesel and other renewable fuels;

• the imposition of windfall profit taxes, maximum margin penalties, minimum inventory requirements or refinery maintenance and turnaround supply plans 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, 2024. 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 product-based value chain each supports: Crude Oil and Products Logistics and Natural Gas and NGL Services.

Our Crude Oil and Products Logistics 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

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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 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 Natural Gas and NGL Services 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. Natural Gas and NGL Services 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, 2025 and September 30, 2024 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.

(1) Non-GAAP measure. See reconciliations that follow for the most directly comparable GAAP measures.

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Other Highlights

• Announced a third quarter 2025 distribution of $1.0765 per common unit, representing a 12.5% increase over the prior quarter’s distribution.

• Returned $1,075 million and $3,229 million of capital to unitholders in the three and nine months ended September 30, 2025, respectively, via distributions and unit repurchases.

• Completed the acquisition of Northwind Delaware Holdings LLC (“Northwind Midstream”) in August 2025 for $2,413 million in cash (the “Northwind Midstream Acquisition”).

• Completed the acquisition of the remaining 55 percent interest in BANGL, LLC (“BANGL”) in July 2025 for $703 million in cash, plus an earnout provision of up to $275 million based on targeted EBITDA growth from 2026 to 2029 (the “BANGL Acquisition”).

• Entered into a definitive agreement in August 2025 to divest its Rockies gathering and processing operations to a subsidiary of Harvest Midstream for $1.0 billion in cash consideration, subject to customary purchase price adjustments.

Current Economic Environment

We continue to see production increases across our key operating regions. In the Marcellus and Utica, rig counts remain steady and volumes remain strong. Producer consolidation further illustrates the value in the liquids-rich acreage of the Utica, where condensate development activity continues to increase. In the Permian, rising gas-oil ratios and the progression of export projects will support growth opportunities for our business. More broadly, we expect natural gas demand will accelerate over the next few years to provide increased electricity generation required for data centers and overall electric grid demand. As demand for natural gas-powered electricity rises, MPLX is well-positioned to support the development plans of its producer-customers. Additionally, MPLX is protected from significant volatility in our Crude Oil and Products Logistics segment and in the Marcellus and Utica regions due to our business model structured around long-term take-or-pay and capacity contracts.

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.

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; (viii) transaction-related costs; and (ix) 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 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

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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.

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)	2025		2024		Variance		2025		2024		Variance
Revenues and other income:
Service revenue	$	1,844	$	1,775	$	69	$	5,406	$	5,152	$	254
Rental income	296		279		17		851		831		20
Product related revenue	615		570		45		1,869		1,620		249
Sales-type lease revenue	150		152		(2)		454		461		(7)
Income from equity method investments	186		149		37		542		631		(89)
Gain on equity method investments	484		—		484		484		20		464
Other income	44		47		(3)		140		155		(15)
Total revenues and other income	3,619		2,972		647		9,746		8,870		876
Costs and expenses:
Cost of revenues (excludes items below)	395		404		(9)		1,153		1,159		(6)
Purchased product costs	493		403		90		1,384		1,148		236
Rental cost of sales	26		27		(1)		73		75		(2)
Purchases - related parties	396		402		(6)		1,234		1,162		72
Depreciation and amortization	346		322		24		996		959		37
General and administrative expenses	126		107		19		345		323		22
Other taxes	36		32		4		101		99		2
Total costs and expenses	1,818		1,697		121		5,286		4,925		361
Income from operations	1,801		1,275		526		4,460		3,945		515
Net interest and other financial costs	243		226		17		706		692		14
Income before income taxes	1,558		1,049		509		3,754		3,253		501
Provision for income taxes	3		2		1		5		5		—
Net income	1,555		1,047		508		3,749		3,248		501
Less: Net income attributable to noncontrolling interests	10		10		—		30		30		—
Net income attributable to MPLX LP	1,545		1,037		508		3,719		3,218		501

Adjusted EBITDA attributable to MPLX LP (1)	1,766		1,714		52		5,213		5,002		211
DCF attributable to MPLX (1)	$	1,468	$	1,446	$	22	$	4,374	$	4,220	$	154

(1) Non-GAAP measure. See reconciliation below to the most directly comparable GAAP measures.

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	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)	2025		2024		2025		2024
Reconciliation of Adjusted EBITDA attributable to MPLX LP and DCF attributable to LP unitholders from Net income:
Net income	$	1,555	$	1,047	$	3,749	$	3,248
Provision for income taxes	3		2		5		5
Net interest and other financial costs	243		226		706		692
Income from operations	1,801		1,275		4,460		3,945
Depreciation and amortization	346		322		996		959
Income from equity method investments	(186)		(149)		(542)		(631)
Distributions/adjustments related to equity method investments	251		253		707		671
Gain on equity method investments	(484)		—		(484)		—
Transaction-related costs (1)	21		—		21		—

Other (2)	28		24		88		91
Adjusted EBITDA	1,777		1,725		5,246		5,035
Adjusted EBITDA attributable to noncontrolling interests	(11)		(11)		(33)		(33)
Adjusted EBITDA attributable to MPLX LP	1,766		1,714		5,213		5,002
Deferred revenue impacts	(6)		(15)		(34)		6
Sales-type lease payments, net of income	21		7		48		20
Adjusted net interest and other financial costs (3)	(236)		(212)		(680)		(651)
Maintenance capital expenditures, net of reimbursements	(70)		(40)		(150)		(120)
Equity method investment maintenance capital expenditures paid out	(4)		(4)		(12)		(11)
Other	(3)		(4)		(11)		(26)
DCF attributable to MPLX LP	1,468		1,446		4,374		4,220
Preferred unit distributions	—		(6)		—		(21)
DCF attributable to LP unitholders	$	1,468	$	1,440	$	4,374	$	4,199

(1) Transaction-related costs include costs associated with acquisition and divestiture-related activities, including significant transactions discussed in Item 1. Financial Statements - Note 3.

(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.

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	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)	2025		2024			2025		2024
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	$	1,431	$	1,415		$	4,413	$	4,271
Changes in working capital items	40		40			(43)		(55)
All other, net	—		(3)			(4)		(13)
Loss on extinguishment of debt	—		—			3		—
Adjusted net interest and other financial costs (1)	236		212			680		651
Other adjustments to equity method investment distributions	15		34			76		75
Transaction-related costs (2)	21		—			21		—

Other	34		27			100		106
Adjusted EBITDA	1,777		1,725			5,246		5,035
Adjusted EBITDA attributable to noncontrolling interests	(11)		(11)			(33)		(33)
Adjusted EBITDA attributable to MPLX LP	1,766		1,714			5,213		5,002
Deferred revenue impacts	(6)		(15)			(34)		6
Sales-type lease payments, net of income	21		7			48		20
Adjusted net interest and other financial costs (1)	(236)		(212)			(680)		(651)
Maintenance capital expenditures, net of reimbursements	(70)		(40)			(150)		(120)
Equity method investment maintenance capital expenditures paid out	(4)		(4)			(12)		(11)
Other	(3)		(4)			(11)		(26)
DCF attributable to MPLX LP	1,468		1,446			4,374		4,220
Preferred unit distributions	—		(6)			—		(21)
DCF attributable to LP unitholders	$	1,468	$	1,440		$	4,374	$	4,199

(1) Represents Net interest and other financial costs excluding gain/loss on extinguishment of debt and amortization of deferred financing costs.

(2) Transaction-related costs include costs associated with acquisition and divestiture-related activities, including significant transactions discussed in Item 1. Financial Statements - Note 3.

Three months ended September 30, 2025 compared to three months ended September 30, 2024

Net income attributable to MPLX increased $508 million in the third quarter of 2025 compared to the third quarter of 2024.

Total revenues and other income increased $647 million in the third quarter of 2025 compared to the third quarter of 2024 primarily due to:

• Increased Service revenue of $69 million primarily due to $32 million of crude oil and products logistics tariff and other fee increases and $28 million from recent acquisitions.

• Increased Product related revenue of $45 million primarily due to higher NGL sales volumes in the Southwest and Marcellus of $89 million, partially offset by lower NGL prices in the Southwest, Marcellus and Southern Appalachia.

• Increased Income from equity method investments of $37 million primarily driven by increased throughput and fee rates in certain processing and pipeline joint ventures. See Supplemental Information on Equity Method Investments for additional information regarding the results of our equity method investments.

• Increased Gain on equity method investments of $484 million from the BANGL Acquisition in the third quarter of 2025.

Total costs and expenses increased by $121 million in the third quarter of 2025 compared to the same period of 2024 primarily due to:

• Decreased Cost of revenues of $9 million primarily due to lower NGL purchases in the Rockies of $29 million, which are now reflected in Purchased product costs due to changes in certain customer contracts, partially offset by $8 million of incremental operating costs as a result of recent acquisitions and $7 million of higher net operating costs and repairs and maintenance costs.

• Increased Purchased product costs of $90 million primarily due to higher NGL volumes in the Southwest of $80 million and higher NGL volumes in the Rockies of $23 million, which were previously recorded in Cost of revenues due to changes in certain customer contracts. The increase was partially offset by lower NGL prices in the Southwest of $10 million.

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• Decreased Purchases - related parties of $6 million primarily due to $17 million of lower related party transportation costs as a result of the BANGL Acquisition, partially offset by increased costs from MPC.

Nine months ended September 30, 2025 compared to nine months ended September 30, 2024

Net income attributable to MPLX increased $501 million in the first nine months of 2025 compared to the same period of 2024.

Total revenues and other income increased $876 million in the first nine months of 2025 compared to the same period of 2024 primarily due to:

• Increased Service revenue of $254 million primarily due to $96 million of crude oil and products logistics tariff and other fee increases and $61 million of higher pipeline throughput. Other increases in the first nine months of 2025 include $46 million from recent acquisitions and $11 million of additional marine equipment.

• Increased Product related revenue of $249 million primarily due to higher NGL sales volumes in the Southwest and Marcellus of $255 million and a $27 million non-recurring benefit associated with a customer agreement.

• Decreased Income from equity method investments of $89 million primarily driven by a $151 million gain in the 2024 period related to the dilution of our ownership interest in connection with the formation of a new joint venture to strategically combine the Whistler Pipeline and the Rio Bravo Pipeline project (the “Whistler Joint Venture Transaction”), partially offset by increased throughput and fee rates in certain processing and pipeline joint ventures and a $25 million gain in the first half of 2025 related to the formation of a new joint venture, Texas City Logistics LLC. See Supplemental Information on Equity Method Investments for additional information regarding the results of our equity method investments.

• Increased Gain on equity method investments of $464 million, primarily driven by a $484 million gain from the BANGL Acquisition, partially offset by a $20 million gain related to the acquisition of additional ownership interest in existing joint ventures and gathering assets in the Utica basin (the “Utica Midstream Acquisition”) in the 2024 period.

• Decreased Other income of $15 million primarily due to higher insurance proceeds of $25 million received in the first nine months of 2024, partially offset by marine services rate increases.

Total costs and expenses increased by $361 million in the first nine months of 2025 compared to the same period of 2024 primarily due to:

• Decreased Cost of revenues of $6 million primarily due to lower NGL purchases in the Rockies of $57 million, which are now reflected in Purchased product costs due to changes in certain customer contracts, and $23 million of lower project-related spending, partially offset by higher net operating costs and repairs and maintenance costs of $57 million and the consolidation of recent acquisitions of $11 million.

• Increased Purchased product costs of $236 million primarily due to higher NGL volumes in the Southwest of $191 million, higher NGL volumes in the Rockies of $46 million, which were previously recorded in Cost of revenues due to changes in certain customer contracts, and higher NGL prices in the Southwest of $16 million. The increases were partially offset by a decrease in the fair value of an embedded derivative in a natural gas purchase commitment of $14 million.

• Increased Purchases - related parties of $72 million primarily due to $69 million of higher employee costs from MPC.

Segment Results

In the fourth quarter of 2024, we renamed and modified the composition of our segments to better reflect the product-based value chains and growth strategy of MPLX’s operations. Certain prior period segment information has been recast for comparability.

We classify our business in the following reportable segments: Crude Oil and Products Logistics and Natural Gas and NGL Services. 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; (vii) transaction-related costs; and (viii) other adjustments, as applicable. These items are either: (i) believed to be non-recurring in nature; (ii) not believed to be allocable or controlled by the segment; or (iii) are not tied to the operational performance of the segment.

The tables below present additional financial information about our reported segments for the three and nine months ended September 30, 2025 and September 30, 2024.

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Crude Oil and Products Logistics Segment

Third Quarter Crude Oil and Products Logistics Segment Financial Highlights (in millions)


	Three Months Ended September 30,						Nine Months Ended September 30,
(In millions)	2025		2024		Variance		2025		2024		Variance






Total segment revenues and other income	$	1,660	$	1,607	$	53	$	4,887	$	4,732	$	155







Segment Adjusted EBITDA	1,137		1,094		43		3,372		3,252		120
Capital expenditures	147		112		35		391		299		92
Investments in unconsolidated affiliates (1)	$	13	$	1	$	12	$	13	$	93	$	(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, 2025 compared to three months ended September 30, 2024

Total segment revenues and other income increased $53 million in the third quarter of 2025 compared to the same period of 2024. This was primarily driven by $39 million of rate increases, $7 million from the March 2025 Whiptail Midstream acquisition and $3 million of additional marine equipment in operation.

Segment Adjusted EBITDA increased $43 million in the third quarter of 2025 compared to the same period of 2024. The increase was driven by $39 million of rate increases, $6 million from the March 2025 Whiptail Midstream acquisition and $3 million of additional marine equipment in operation. These increases were partially offset by higher operating costs of $8 million driven primarily by higher employee costs from MPC and increased energy costs.

Nine months ended September 30, 2025 compared to nine months ended September 30, 2024

Total segment revenues and other income increased $155 million the first nine months of 2025 compared to the same period of 2024. This was primarily driven by $108 million of rate increases, $63 million of increased pipeline throughput, $16 million from the March 2025 Whiptail Midstream acquisition and $11 million of additional marine equipment in operation, partially offset by lower insurance proceeds of $25 million. Income from equity method investments decreased $27 million the first nine months of 2025 compared to the same period of 2024, primarily driven by lower throughputs at certain equity method investments. See Supplemental Information on Equity Method Investments for additional information regarding the results of our equity method investments.

Segment Adjusted EBITDA increased $120 million the first nine months of 2025 compared to the same period of 2024. The increase was driven by $108 million of rate increases, $63 million of increased pipeline throughput, $13 million from the March 2025 Whiptail Midstream acquisition and $11 million of additional marine equipment in operation. These increases were partially offset by higher operating costs of $33 million driven primarily by higher employee costs from MPC and increased energy costs as a result of higher throughputs, as well as lower distributions from equity method investments of $17 million and higher project related spending of $12 million. Additionally, the first nine months of 2025 reflects $25 million of lower insurance proceeds as compared to the first nine months of 2024.

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Crude Oil and Products Logistics Operating Data


	Three Months Ended September 30,				Nine Months Ended September 30,
	2025		2024		2025		2024
Crude Oil and Products Logistics
Pipeline throughput (mbpd)
Crude oil pipelines	3,867		3,895		3,929		3,769
Product pipelines	2,055		2,056		2,056		1,987
Total pipelines	5,922		5,951		5,985		5,756

Average tariff rates ($ per barrel) (1)
Crude oil pipelines	$	1.08	$	1.01	$	1.06	$	1.01
Product pipelines	1.09		1.01		1.08		0.99
Total pipelines	$	1.08	$	1.01	$	1.07	$	1.00

Terminal throughput (mbpd)	3,173		3,268		3,151		3,132



Marine Assets (number in operation) (2)
Barges	320		311		320		311
Towboats	29		28		29		28

(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.

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Natural Gas and NGL Services Segment

Third Quarter Natural Gas and NGL Services Segment Financial Highlights (in millions)


	Three Months Ended September 30,						Nine Months Ended September 30,
(In millions)	2025		2024		Variance		2025		2024		Variance







Total segment revenues and other income	$	1,959	$	1,365	$	594	$	4,859	$	4,138	$	721








Segment Adjusted EBITDA	629		620		9		1,841		1,750		91
Capital expenditures	447		189		258		812		421		391
Investments in unconsolidated affiliates	$	227	$	31	$	196	$	549	$	93	$	456

Three months ended September 30, 2025 compared to three months ended September 30, 2024

Total segment revenues and other income increased $594 million in the third quarter of 2025 compared to the same period of 2024 primarily due to the recognition of a $484 million gain from the BANGL Acquisition. Revenues in the third quarter of 2025 benefited from $89 million of higher NGL sales volumes in the Southwest and Marcellus and $21 million from recent acquisitions, partially offset by lower NGL prices in the Southwest, Marcellus and Southern Appalachia. Income from equity method investments increased $36 million, primarily due to increased throughput and fee rates in certain processing and pipeline joint ventures. See Supplemental Information on Equity Method Investments for additional information regarding the results of our equity method investments.

Segment Adjusted EBITDA increased $9 million in the third quarter of 2025 compared to the same period of 2024. This increase is primarily due to contributions from recent acquisitions of $37 million and higher throughput fee rates of $10 million, partially offset by lower volumes in the Rockies and Bakken of $12 million, higher operating costs of $11 million and lower NGL prices of $8 million.

Nine months ended September 30, 2025 compared to nine months ended September 30, 2024

Total segment revenues and other income increased $721 million in the first nine months of 2025 compared to the same period of 2024 primarily due to the recognition of a $484 million gain from the BANGL Acquisition, $255 million of higher NGL sales volumes in the Southwest and Marcellus, a $34 million non-recurring benefit associated with a customer agreement and $30 million from recent acquisitions. These increases were partially offset by lower income from equity method investments of $62 million, primarily driven by a $151 million gain in the second quarter of 2024 related to the dilution of our ownership interest in connection with the Whistler Joint Venture Transaction.

Additional impacts from equity method investments included increased throughput and fee rates in certain processing and pipeline joint ventures, a $25 million gain in the first nine months of 2025 related to the formation of a new joint venture, Texas City Logistics LLC, and a $6 million benefit from the Utica Midstream Acquisition that was completed in the first quarter of 2024. See Supplemental Information on Equity Method Investments for additional information regarding the results of our equity method investments.

Segment Adjusted EBITDA increased $91 million in the first nine months of 2025 compared to the same period of 2024. This increase is primarily due to $44 million of higher distributions and adjustments from equity method investments, $37 million in contributions from recent acquisitions, a $37 million non-recurring benefit associated with a customer agreement and $30 million of higher throughput fee rates, partially offset by higher operating costs of $34 million and lower volumes in the Rockies and Bakken of $27 million.

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Natural Gas and NGL Services Operating Data

(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,
	2025	2024	2025	2024
Natural Gas and NGL Services
Gathering Throughput (MMcf/d)
Marcellus Operations	1,517	1,527	1,517	1,527
Utica Operations	—	354	2,754	2,616
Southwest Operations (3)	1,882	1,813	1,882	1,813
Bakken Operations	157	181	157	181
Rockies Operations	529	542	596	600
Total gathering throughput	4,085	4,417	6,906	6,737

Natural Gas Processed (MMcf/d)
Marcellus Operations	4,466	4,393	6,180	6,013
Utica Operations	—	—	983	794
Southwest Operations	1,983	1,977	1,983	1,977
Southern Appalachia Operations	168	215	168	215
Bakken Operations	157	179	157	179
Rockies Operations	604	597	604	597
Total natural gas processed	7,378	7,361	10,075	9,775

C2 + NGLs Fractionated (mbpd)
Marcellus Operations (4)	580	550	580	550
Utica Operations (4)	—	—	67	48
Southern Appalachia Operations	11	12	11	12
Bakken Operations	14	20	14	20
Rockies Operations	5	5	5	5
Total C2 + NGLs fractionated (5)	610	587	677	635

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	MPLX LP (1)		MPLX LP Operated (2)
	Nine Months Ended September 30		Nine Months Ended September 30
	2025	2024	2025	2024
Natural Gas and NGL Services
Gathering Throughput (MMcf/d)
Marcellus Operations	1,501	1,515	1,501	1,515
Utica Operations	88	239	2,587	2,522
Southwest Operations (3)	1,801	1,668	1,801	1,668
Bakken Operations	165	183	165	183
Rockies Operations	539	563	609	639
Total gathering throughput	4,094	4,168	6,663	6,527

Natural Gas Processed (MMcf/d)
Marcellus Operations	4,368	4,360	6,059	5,963
Utica Operations	—	—	962	801
Southwest Operations	1,895	1,786	1,895	1,786
Southern Appalachian Operations	187	218	187	218
Bakken Operations	164	182	164	182
Rockies Operations	599	622	599	622
Total natural gas processed	7,213	7,168	9,866	9,572

C2 + NGLs Fractionated (mbpd)
Marcellus Operations (4)	564	558	564	558
Utica Operations (4)	—	—	64	49
Southern Appalachian Operations	10	12	10	12
Bakken Operations	14	20	14	20
Rockies Operations	5	5	5	5
Total C2 + NGLs fractionated (5)	593	595	657	644

(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) In addition to the amounts presented, Northwind Midstream treated volumes during the three and nine months ended September 30, 2025 were 36 MMcf/d and 12 MMcf/d, respectively.

(4) 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.

(5) Purity ethane makes up approximately 279 mbpd and 246 mbpd of MPLX LP consolidated total fractionated products for the three months ended September 30, 2025 and September 30, 2024, respectively, and approximately 267 mbpd and 258 mbpd of total fractionated products for the nine months ended September 30, 2025 and September 30, 2024, respectively. Purity ethane makes up approximately 300 mbpd and 262 mbpd of MPLX LP Operated total fractionated products for the three months ended September 30, 2025 and September 30, 2024, respectively, and approximately 287 mbpd and 273 mbpd of total fractionated products for the nine months ended September 30, 2025 and September 30, 2024, respectively.


	Three Months Ended September 30,				Nine Months Ended September 30,
	2025		2024		2025		2024
Pricing Information
Natural Gas NYMEX HH ($ per MMBtu)	$	3.07	$	2.23	$	3.48	$	2.22
C2 + NGL Pricing ($ per gallon) (1)	$	0.74	$	0.80	$	0.82	$	0.84

(1) C2 + NGL pricing based on Mont Belvieu prices assuming an NGL barrel of approximately 10 percent ethane, 60 percent propane, five percent Iso-Butane, 15 percent normal butane and 10 percent natural gasoline.

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Supplemental Information on Equity Method Investments

The following table presents MPLX’s income from equity method investments for the three and nine months ended September 30, 2025 and September 30, 2024:


	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)	2025		2024			2025		2024
Income from equity method investments:
Crude Oil and Products Logistics
Illinois Extension Pipeline Company, L.L.C.	$	12	$	15		$	39	$	44
LOOP LLC	6		3			9		9
MarEn Bakken Company LLC	17		23			60		76








Other	36		29			78		84
Total Crude Oil and Products Logistics	71		70			186		213
Natural Gas and NGL Services
MarkWest EMG Jefferson Dry Gas Gathering Company, L.L.C.	19		17			55		53
MarkWest Utica EMG, L.L.C.	35		19			94		57
Ohio Gathering Company L.L.C.	10		4			26		7
Sherwood Midstream LLC	29		27			86		81
WPC Parent, LLC (1)	21		16			62		218














Other (2)	1		(4)			33		2
Total Natural Gas and NGL Services	115		79			356		418
Total	$	186	$	149		$	542	$	631

(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 includes a gain of $151 million related to the dilution of our ownership interest in connection with the Whistler Joint Venture Transaction.

(2) Includes a $25 million gain in the first nine months of 2025 related to the formation of a new joint venture, Texas City Logistics LLC.

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, 2025 and September 30, 2024:


	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)	2025		2024			2025		2024
Distributions/adjustments related to equity method investments:
Crude Oil and Products Logistics
Illinois Extension Pipeline Company, L.L.C.	$	16	$	18		$	38	$	41
LOOP LLC	4		5			21		14
MarEn Bakken Company LLC	25		27			78		87








Other	39		37			96		109
Total Crude Oil and Products Logistics	84		87			233		251
Natural Gas and NGL Services
MarkWest EMG Jefferson Dry Gas Gathering Company, L.L.C.	23		22			53		62
MarkWest Utica EMG, L.L.C.	46		32			124		90
Ohio Gathering Company L.L.C.	17		13			47		24
Sherwood Midstream LLC	34		28			95		90
WPC Parent, LLC (1)	29		56			90		123













Other	18		15			65		31
Total Natural Gas and NGL Services	167		166			474		420
Total	$	251	$	253		$	707	$	671

(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.

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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 Crude Oil and Products Logistics segment’s revenues are mitigated through the use of capacity-based agreements and minimum volume commitments.

In our Natural Gas and NGL Services 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.

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Liquidity and Capital Resources

Cash Flows

Our cash and cash equivalents were $1,765 million at September 30, 2025 and $1,519 million at December 31, 2024. 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)	2025		2024
Net cash provided by (used in):
Operating activities	$	4,413	$	4,271
Investing activities	(4,934)		(1,646)
Financing activities	767		(1,247)
Total	$	246	$	1,378

Net cash provided by operating activities increased $142 million in the first nine months of 2025 compared to the same period of 2024, primarily due to improved results from operations and higher cash distributions from equity method investments.

Net cash used in investing activities increased $3,288 million in the first nine months of 2025 compared to the same period of 2024, primarily due to the acquisition of Northwind Midstream for $2,413 million, the purchase of the remaining 55 percent interest in BANGL for $703 million, the purchase of an additional five percent ownership interest in the joint venture that owns and operates the Matterhorn Express pipeline for $151 million, higher capital spending and a $134 million cash distribution received in the second quarter of 2024 in connection with the Whistler Joint Venture Transaction.

Net cash provided by financing activities increased $2,014 million in the first nine months of 2025 compared to the same period of 2024, primarily driven by increased net debt borrowings of $2,448 million, partially offset by higher distributions to unitholders of $306 million as a result of the 12.5 percent increase in our quarterly distribution effective for the third quarter of 2024, and higher unit repurchases of $74 million.

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, 2025 and September 30, 2024.


	Three Months Ended September 30,				Nine Months Ended September 30,
(In millions)	2025		2024		2025		2024
Net cash provided by operating activities (1)	$	1,431	$	1,415	$	4,413	$	4,271
Adjustments to reconcile net cash provided by operating activities to adjusted free cash flow
Net cash used in investing activities (2)	(3,731)		(536)		(4,934)		(1,646)
Contributions from MPC	6		8		20		26
Distributions to noncontrolling interests	(11)		(11)		(33)		(33)
Adjusted FCF	(2,305)		876		(534)		2,618




Distributions paid to common and preferred unitholders	(975)		(873)		(2,929)		(2,623)
Adjusted FCF after distributions	$	(3,280)	$	3	$	(3,463)	$	(5)

(1) The three months ended September 30, 2025 and September 30, 2024 include working capital builds of $40 million and $40 million, respectively. The nine months ended September 30, 2025 and September 30, 2024 include working capital draws of $43 million and $55 million, respectively.

(2) The three and nine months ended September 30, 2025 include $703 million f or the BANGL Acquisition, $2.4 billion for the Northwind Midstream Acquisition, a $49 million capital contribution to WPC Parent, LLC to purchase Enbridge's special membership interest in the Rio Bravo Pipeline project, and a $13 million payment related to an earnout associated with MXP Parent, LLC. The nine months ended September 30, 2025 also includes the Whiptail Midstream acquisition for $237 million and $151 million related to the acquisition of additional interest in the joint venture that owns and operates Matterhorn Express Pipeline. The three and nine months ended September 30, 2024 include $210 million and $18 million related to the acquisition of additional interests in BANGL and Wink to Webster Pipeline, LLC, respectively. The nine months ended September 30, 2024 also includes the Utica Midstream Acquisition for $625 million, a $134 million cash distribution received in connection with the Whistler Joint Venture Transaction, and a contribution of $92 million to Dakota Access to fund our share of a debt repayment by the joint venture.

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Debt and Liquidity Overview

The following table summarizes debt issuances during the nine months ended September 30, 2025, all of which were issued in an underwritten public offering:


Issue Date	Aggregate Principal Amount (in millions)		Note(s)	Coupon (percent)	Price to Public (percent of par)	Interest Payment Dates	Maturity Date
March 10, 2025	$	1,000	(1)	5.400	99.398	April 1 and October 1	April 1, 2035
March 10, 2025	1,000		(1)	5.950	98.331	April 1 and October 1	April 1, 2055
August 11, 2025	1,250		(2)	4.800	99.880	February 15 and August 15	February 15, 2031
August 11, 2025	750		(2)	5.000	98.936	January 15 and July 15	January 15, 2033
August 11, 2025	1,500		(2)	5.400	98.943	March 15 and September 15	September 15, 2035
August 11, 2025	$	1,000	(2)	6.200	98.277	March 15 and September 15	September 15, 2055

(1) On April 9, 2025, MPLX used $1.2 billion of the net proceeds from the issuance of senior notes in March 2025 to redeem all of (i) MPLX’s outstanding $1,189 million aggregate principal amount of 4.875 percent senior notes due June 2025 and (ii) MarkWest’s outstanding $11 million aggregate principal amount of 4.875 percent senior notes due June 2025. MPLX intends to use the remaining net proceeds for general partnership purposes.

(2) We used a portion of the net proceeds from this offering to fund the Northwind Midstream Acquisition, including the payment of related fees and expenses, and to increase cash and cash equivalents following the recently completed BANGL Acquisition and BANGL debt repayment. We intend to use the remainder of the net proceeds from this offering for general partnership purposes, which may include capital expenditures and working capital.

On February 18, 2025, MPLX repaid all of MPLX’s outstanding $500 million aggregate principal amount of 4.000 percent senior notes due February 2025 at maturity.

On July 3, 2025, MPLX used cash on hand to extinguish approximately $656 million principal amount of debt outstanding, including interest, related to certain term and revolving loans assumed as part of the BANGL Acquisition. See Note 3 to the unaudited consolidated financial statements for additional information on the BANGL Acquisition.

Our intention is to maintain an investment-grade credit profile. As of September 30, 2025, the credit ratings on our senior unsecured debt were at or above investment grade level as follows:


Rating Agency						Rating
Fitch						BBB (stable outlook)
Moody’s						Baa2 (stable outlook)
Standard & Poor’s						BBB (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 MPLX’s credit agreement (the “MPLX Credit Agreement”) and may limit our ability to obtain future financing, including refinancing existing indebtedness.

Our liquidity totaled $5.3 billion at September 30, 2025 consisting of:


	September 30, 2025
(In millions)	Total Capacity		Outstanding Borrowings		Available Capacity
MPLX Credit Agreement	$	2,000	$	—	$	2,000

MPC Loan Agreement	1,500		—		1,500
Total	$	3,500	$	—	3,500
Cash and cash equivalents					1,765
Total liquidity					$	5,265

We expect our ongoing sources of liquidity to include cash generated from operations, 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

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obligations, and quarterly cash distributions. Our material future obligations include interest on debt, payments of debt principal, purchase obligations including contracts to acquire property, plant and equipment, and our operating leases and service agreements. We may also, from time to time, repurchase our senior notes 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.

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, 2025, we were in compliance with such covenants.

MPLX is party to a loan agreement with MPC, which is 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.

Equity and Preferred Units Overview

Unit Repurchase Program

On August 5, 2025, we announced a board authorization for the repurchase of up to $1.0 billion of MPLX common units held by the public in addition to the $1.0 billion common unit repurchase authorization announced on August 2, 2022. The common unit repurchase authorizations have 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)	2025		2024		2025		2024
Number of common units repurchased	2		2		6		5
Cash paid for common units repurchased (1)	$	100	$	76	$	300	$	226
Average cost per unit (1)	$	50.86	$	42.89	$	51.20	$	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, 2025, we had $1.2 billion remaining under the unit repurchase authorizations.

Series A Redeemable Preferred Unit Conversions

Distributions

On October 28, 2025, MPLX declared a cash distribution for the third quarter of 2025, totaling $1,095 million, or $1.0765 per common unit. This distribution will be paid on November 14, 2025, to common unitholders of record on November 7, 2025. 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.

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The allocation of total cash distributions is as follows for the three and nine months ended September 30, 2025 and September 30, 2024. 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)	2025		2024		2025		2024
Distribution declared:
Limited partner units - public	$	397	$	355	$	1,110	$	986
Limited partner units - MPC	698		619		1,936		1,720




Total LP distribution declared	1,095		974		3,046		2,706
Series A preferred units	—		6		—		21

Total distribution declared	$	1,095	$	980	$	3,046	$	2,727

Quarterly cash distributions declared per limited partner common unit	$	1.0765	$	0.9565	$	2.9895	$	2.6565

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 income from operations 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 expenditures 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 to maintain existing system volumes and related cash flows.

MPLX’s initial capital investment plan for 2025 is $2.0 billion, net of reimbursements and excluding capitalized interest, acquisitions and any incremental capital project expenditures associated with acquisitions made during the year. The initial capital investment plan includes growth capital of $1.7 billion and maintenance capital of $300 million. Growth capital expenditures and investments in affiliates during the nine months ended September 30, 2025 were primarily for expanding our Permian to Gulf Coast integrated natural gas and NGL value chain, gas processing plants in the Marcellus and Permian basins and gas gathering projects in the Marcellus, Utica and Permian basins. We continuously evaluate our capital plan and make changes as conditions warrant.

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Our capital expenditures are shown in the table below:


	Nine Months Ended September 30,
(In millions)	2025		2024
Capital expenditures:
Growth capital expenditures	$	1,019	$	569
Growth capital reimbursements	(100)		(64)
Investments in unconsolidated affiliates (1)	562		186
Return of capital (2)	(101)		(4)
Capitalized interest	(22)		(12)
Total growth capital expenditures (3)	1,358		675
Maintenance capital expenditures	184		151
Maintenance capital reimbursements	(34)		(31)
Capitalized interest	(3)		(2)
Total maintenance capital expenditures	147		118

Total growth and maintenance capital expenditures	1,505		793
Investments in unconsolidated affiliates (1)	(562)		(186)
Return of capital (2)	101		4
Growth and maintenance capital reimbursements (4)	134		95
(Increase)/Decrease in capital accruals	(131)		28
Capitalized interest	25		14
Other	22		—
Additions to property, plant and equipment	$	1,094	$	748

(1) 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. Investments in unconsolidated affiliates for the nine months ended September 30, 2025 exclude $151 million related to the acquisition of additional interest in the joint venture that owns and operates the Matterhorn Express Pipeline, a $49 million capital contribution to WPC Parent, LLC to purchase Enbridge’s special membership interest in the Rio Bravo Pipeline project, and a $13 million payment related to earnout associated with MXP Parent, LLC. 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 and Wink to Webster Pipeline LLC, respectively.

(2) Return of capital for the nine months ended September 30, 2025 excludes $42 million in special distributions received in exchange for the contribution of assets to a joint venture. Return of capital for the nine months ended September 30, 2024 excludes a $134 million cash distribution in connection with the Whistler Joint Venture Transaction.

(3) Total growth capital expenditures for the nine months ended September 30, 2025 and September 30, 2024 exclude acquisitions of $3,316 million and $622 million, net of cash acquired, respectively.

(4) 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 of our joint ventures fund capital expenditures with project debt financings at the joint venture level or with cash from operations. Growth capital projects funded through debt at the joint venture level or cash from operations of the joint venture do not require capital contributions by us unless otherwise noted. Our pro-rata share of these growth capital projects for our equity method investments that have been funded at the joint venture level for the periods presented are shown in the table below.


	MPLX Ownership		Nine Months Ended September 30,
(In millions, except ownership percentages)		2025			2024
BANGL, LLC (1)	100%		$	60		$	84
MXP Parent, LLC (2)	10%		12			47
WPC Parent, LLC (3)	30%		63			18
All other			6			43
Total			$	141		$	192

(1) The nine months ended September 30, 2025 reflect activity through June 30, 2025, prior to the BANGL Acquisition.

(2) Includes growth capital for Matterhorn Express Pipeline.

(3) Disclosed amounts include growth capital related to WPC Parent, LLC, including the ADCC Pipeline lateral, Rio Bravo Pipeline, Whistler Pipeline, and our indirect and 12.5 percent direct ownership interest in Blackcomb and Traverse Pipeline Holdings, LLC.

Project debt at the joint venture level is typically secured by the assets owned by the joint venture and in certain cases, MPLX’s interest in the joint venture, but unless otherwise noted, is non-recourse to MPLX in excess of the value of MPLX’s investment in the joint venture. At September 30, 2025, debt held by our unconsolidated joint ventures based on our equity ownership

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percentage was $1.6 billion. See Note 16 to the accompanying unaudited consolidated financial statements for more information on MPLX’s guarantees of our joint venture entities’ obligations.

Cash Commitments

As of September 30, 2025, 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, 2025, our debt obligations increased by $4.8 billion due to the issuance of senior notes and the repayment of 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, 2024.

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, 2025, 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,
	2025		2024		2025		2024
Total revenues and other income (1)	47	%	49	%	48	%	50	%
Total costs and expenses	26	%	27	%	26	%	27	%

(1) The three and nine months ended September 30, 2025 exclude the gain on equity method investments related to the BANGL Acquisition. The nine months ended September 30, 2024 excludes the 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, 2024, 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 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, 2024, 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, 2024.

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, 2025, 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, 2024 except as noted below.

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Acquisitions

In accounting for business combinations, acquired assets, assumed liabilities and contingent consideration are recorded based on estimated fair values as of the date of acquisition. The excess or shortfall of the purchase price when compared to the fair value of the net tangible and identifiable intangible assets acquired, if any, is recorded as goodwill or a bargain purchase gain, respectively. A significant amount of judgment is involved in estimating the individual fair values of property, plant and equipment, intangible assets, contingent consideration and other assets and liabilities. We use all available information to make these fair value determinations and, for certain acquisitions, engage third-party consultants for valuation assistance.

The fair value of assets and liabilities, including contingent consideration, as of the acquisition date are often estimated using a combination of approaches, including the income approach, which requires us to project future cash flows and associated volumes, and apply an appropriate discount rate; the cost approach, which requires estimates of replacement costs and depreciation and obsolescence estimates; and the market approach which uses market data and adjusts for entity-specific differences. The estimates used in determining fair values are based on assumptions believed to be reasonable but which are inherently uncertain. Accordingly, actual results may differ materially from the projected results used to determine fair value.

See Note 3 to the unaudited consolidated financial statements for additional information on our acquisitions. See Note 10 to the unaudited consolidated financial statements for additional information on fair value measurements.

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, 2025, we did not have any open financial or commodity derivative instruments to hedge the economic risks related to interest rate fluctuations or the volatility of commodity prices, respectively; 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, 2025 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, 2024.

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, 2025 (1)		Change in Fair Value (2)		Change in Income Before Income Taxes for the Nine Months Ended September 30, 2025 (3)
Outstanding debt
Fixed-rate	$	24,890	$	2,054	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, 2025.

(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, 2025.

(4) MPLX had no outstanding borrowings on the MPLX Credit Agreement as of September 30, 2025.

At September 30, 2025, 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

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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 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, 2025, 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, 2025, 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.

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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.

Except as described below, 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, 2024.

On August 29, 2025, MPLX acquired Northwind Midstream, including its subsidiary Northwind Midstream Partners LLC, which owns and operates a sour gas treating facility in Lea County, New Mexico. We have disclosed to the New Mexico Environment Department (“NMED”) excess air emissions from the facility flares and have initiated discussions with NMED to resolve this matter. We do not believe any civil penalty will have a material impact on our consolidated results of operations, financial position or cash flows.

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, 2024.

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, 2025, of equity securities that are registered by MPLX pursuant to Section 12 of the Exchange Act.


					Millions of Dollars
Period	Total 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)
7/1/2025-7/31/2025	518,089	$	50.96	518,089	$	294
8/1/2025-8/31/2025	250,050	51.19		250,050	1,281
9/1/2025-9/30/2025	1,197,987	50.75		1,197,987	1,220
Total	1,966,126	50.86		1,966,126

(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 a board authorization for the repurchase of up to $1.0 billion of MPLX common units held by the public. On August 5, 2025, we announced a board authorization for the repurchase of up to an incremental $1.0 billion of MPLX common units held by the public. These unit repurchase authorizations have no expiration date.

(3) T he maximum dollar value remaining has been reduced by the amount of any commissions paid to brokers.

Item 5. Other Information

During the quarter ended September 30, 2025, 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).

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Item 6. Exhibits

Incorporated by Reference From

Exhibit
Number

Exhibit Description

Form

Exhibit

Filing Date

SEC File No.

Filed
Herewith

Furnished
Herewith

3.1

Certificate of Limited Partnership of MPLX LP

S-1

3.1

7/2/2012

333-182500

3.2

Amendment to the Certificate of Limited Partnership of MPLX LP

S-1/A

3.2

10/9/2012

333-182500

3.3

Sixth Amended and Restated Agreement of Limited Partnership of MPLX LP, dated as of February 1, 2021

8-K

3.1

2/3/2021

001-35714

Pursuant to Item 601(b)(4) of Regulation S-K, certain instruments with respect to long-term debt issues have been omitted where the amount of securities authorized under such instruments does not exceed 10 percent of the total consolidated assets of the Registrant. The Registrant hereby agrees to furnish a copy of any such instrument to the Securities and Exchange Commission upon its request.

10.1

Tenth Amendment to the Third Amended and Restated Terminal Services Agreement, dated March 1, 2017, between MPLX Terminals LLC and Marathon Petroleum Company LP

10.2

MPLX LP 2018 Incentive Compensation Plan MPC Non-Employee Director Phantom Unit Award Policy, as amended and restated effective August 25, 2025

10.3

MPLX GP LLC Non-Management Director Compensation Policy, as amended and restated effective August 25, 2025

31.1

Certification of Chief Executive Officer pursuant to Rule 13a-14 and 15d-14 under the Securities Exchange Act of 1934

31.2

Certification of Chief Financial Officer pursuant to Rule 13a-14 and 15d-14 under the Securities Exchange Act of 1934

32.1

Certification of Chief Executive Officer pursuant to 18 U.S.C. Section 1350

32.2

Certification of Chief Financial Officer pursuant to 18 U.S.C. Section 1350

101.INS

XBRL 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.SCH

Inline XBRL Taxonomy Extension Schema Document.

101.CAL

Inline XBRL Taxonomy Extension Calculation Linkbase Document.

101.DEF

Inline XBRL Taxonomy Extension Definition Linkbase Document.

101.LAB

Inline XBRL Taxonomy Extension Label Linkbase Document.

101.PRE

Inline XBRL Taxonomy Extension Presentation Linkbase Document.

104

Cover Page Interactive Data File (formatted as Inline XBRL and contained in Exhibit 101).

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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 4, 2025	By:	/s/ Rebecca L. Iten
		Rebecca L. Iten
		Vice President and Controller of MPLX GP LLC (the general partner of MPLX LP)

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Part I Financial Information Item 1. Financial Statements Item 2. Management S Discussion and Analysis Of Financial Condition and Results Of Operations Item 3. Quantitative and Qualitative Disclosures About Market Risk Item 4. Controls and Procedures Part II Other Information Item 1. Legal Proceedings Item 1A. Risk Factors Item 2. Unregistered Sales Of Equity Securities and Use Of Proceeds Item 5. Other Information Item 6. Exhibits

Exhibits

3.1 Certificate of Limited Partnership of MPLX LP S-1 3.1 7/2/2012 333-182500 3.2 Amendment to the Certificate of Limited Partnership of MPLX LP S-1/A 3.2 10/9/2012 333-182500 3.3 Sixth Amended and Restated Agreement of Limited Partnership of MPLX LP, dated as of February 1, 2021 8-K 3.1 2/3/2021 001-35714 10.1 Tenth Amendment to the Third Amended and Restated Terminal Services Agreement, dated March 1, 2017, between MPLX Terminals LLC and Marathon Petroleum Company LP 10.2 MPLX LP 2018 Incentive Compensation Plan MPC Non-Employee Director Phantom Unit Award Policy, as amended and restated effective August 25, 2025 10.3 MPLX GP LLC Non-Management Director Compensation Policy, as amended and restated effective August 25, 2025 31.1 Certification of Chief Executive Officer pursuant to Rule 13a-14 and 15d-14 under the Securities Exchange Act of 1934 31.2 Certification of Chief Financial Officer pursuant to Rule 13a-14 and 15d-14 under the Securities Exchange Act of 1934 32.1 Certification of Chief Executive Officer pursuant to 18 U.S.C. Section 1350 32.2 Certification of Chief Financial Officer pursuant to 18 U.S.C. Section 1350

MPLX 10-Q Quarter ended Sept. 30, 2025

Exhibits