MPLX Mplx LP - 10-K

Item 1A. Risk Factors

You should carefully consider each of the following risks and all the other information contained in this Annual Report on Form 10-K in evaluating us and our common units. Although the risks are organized by headings, and each risk is discussed separately, many are interrelated. Our business, financial condition, results of operations and cash flows could be materially and adversely affected by these risks, and, as a result, the trading price of our common units could decline. We have in the past been adversely affected by certain of, and may in the future be affected by, these risks.

Summary of Risk Factors

We have in the past been adversely affected by certain of, and may in the future be adversely affected by, the following:

• a significant decrease in crude oil and natural gas production in our areas of operation;

• challenges in accurately estimating expected production volumes of our producer customers;

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• our dependence on third parties for the crude oil, natural gas and refined products we gather, transport and store, the natural gas we process, and the NGLs we fractionate and stabilize at our facilities;

• our ability to retain existing customers or acquire new customers;

• our ability to increase fees enough to cover costs incurred under our gathering, treating, processing, transmission, transportation, fractionation, stabilization and storage agreements;

• unplanned maintenance of the United States (“U.S.”) inland waterway infrastructure;

• interruptions in operations at any of our facilities or those of our customers, including MPC;

• inflation;

• problems affecting our information technology systems and those of our third-party business partners and service providers;

• business, compliance and reputational risks associated with increasing regulatory focus on data privacy issues, integrating artificial intelligence into our processes and expanding laws in those areas;

• in our joint ventures, our lack of sole decision-making authority, our reliance on our joint venture partners’ financial condition and disputes between us and our joint venture partners;

• terrorist attacks or other targeted operational disruptions aimed at our facilities or that impact our customers or the markets we serve;

• increases to our maintenance or repair costs;

• severe weather events, other climate conditions and earth movement and other geological hazards;

• insufficient cash from operations after the establishment of cash reserves and payment of our expenses to enable us to pay the intended quarterly distribution to our unitholders;

• our substantial debt and other financial obligations;

• increases in interest rates;

• our exposure to the credit risks of our key customers and derivative counterparties;

• negative effects of our commodity derivative activities;

• uninsured losses;

• future costs relating to evolving environmental or other laws or regulations;

• increased regulation of hydraulic fracturing;

• climate-related and GHG emission regulation;

• climate-related litigation;

• societal and political pressures and other forms of opposition to the future development, transportation and use of carbon-based fuels;

• market deterioration prior to the completion of large capital projects;

• increasing attention to ESG matters;

• goals, targets and disclosures related to ESG matters;

• federal and tribal approvals, regulations and lawsuits relating to our facilities that are located on Native American tribal lands;

• our ability to maintain or obtain real property rights required for our business;

• the consequences resulting from foreign investment in us or our general partner exceeding certain levels;

• federal or state rate and service regulation or rate-making policies;

• costs and liabilities resulting from performance of pipeline integrity programs and related repairs;

• future impairments;

• difficulties in making strategic acquisitions on economically acceptable terms from MPC or third parties;

• integration risks from significant future acquisitions;

• the failure by MPC to satisfy its obligations to us, or a significant reduction in volumes transported through our facilities or stored at our storage assets;

• MPC materially suspending, reducing or terminating its obligations under its agreements with us;

• MPC’s level of indebtedness or credit ratings;

• various tax risks inherent in our master limited partnership structure, including the potential for unexpected tax liabilities for us or our unitholders, more burdensome tax filing requirements and future legislative changes to the expected tax treatment of an investment in us;

• MPC’s conflicts of interest with us, its limited duties to us and our unitholders, and its potential favoring of its interests over our interests and the interests of our unitholders;

• the requirements and restrictions arising under our Sixth Amended and Restated Agreement of Limited Partnership, dated as of February 1, 2021 (“Partnership Agreement”), including the requirement that we distribute all of our available

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cash, limitations on our general partner’s duties, limited unitholder voting rights, and limited unitholder recourse in the event unitholders are dissatisfied with our operations;

• cost reimbursements and fees paid to our general partner and its affiliates, which in certain circumstances are subject to our general partner’s sole discretion;

• control of our general partner being transferred to a third party without unitholder consent;

• the issuance of additional units resulting in the dilution of limited unitholder interests, which issuances may be made without unitholder approval;

• the sale of units - and the adverse impact on the trading price of the common units which might result from such sale - by MPC of the units it holds in public or private markets, and such sales could have an adverse impact on the trading price of the common units;

• affiliates of our general partner, including MPC, competing with us, and neither our general partner nor its affiliates having any obligation to present business opportunities to us;

• our general partner having a limited call right that may require unitholders to sell common units at an undesirable time or price;

• a unitholder’s liability not being limited if a court finds that unitholder action constitutes control of our business;

• unitholders may have to repay distributions that were wrongfully distributed to them;

• the NYSE not requiring a publicly traded limited partnership like us to comply with certain of its corporate governance requirements; and

• the Court of Chancery of the State of Delaware being, to the extent permitted by law, the sole and exclusive forum for substantially all disputes between us and our limited partners.

Business and Operational Risks

A significant decrease in crude oil and natural gas production in our areas of operation may adversely affect our business, financial condition, results of operations and cash available for distribution.

A significant portion of our operations is dependent on the continued availability of natural gas and crude oil production. The production from oil and natural gas reserves and wells owned by our producer customers will naturally decline over time, which means that our cash flows associated with these wells will also decline over time. To maintain or increase throughput levels and the utilization rate of our facilities, we must continually obtain new oil, natural gas, NGL and refined product supplies, which depend in part on the level of successful drilling activity near our facilities, our ability to compete for volumes from successful new wells and our ability to expand our system capacity as needed.

We have no control over the level of drilling activity in the areas of our operations, the amount of reserves associated with the wells or the rate at which production from a well will decline. In addition, we have no control over producers or their production decisions, which are affected by demand, prevailing and projected energy prices, drilling costs, operational challenges, access to downstream markets, the level of reserves, geological considerations, governmental regulations and the availability and cost of capital. Reductions or changes in exploration or production activity in our areas of operations could lead to reduced throughput on our pipelines and utilization rates of our facilities.

Fluctuations in energy prices can negatively affect drilling activity, production rates and investments by third parties in the development of new oil and natural gas reserves. The prices for oil, natural gas and NGLs depend upon factors beyond our control, including global and regional demand, production levels, changes in interstate pipeline gas quality specifications, imports and exports, seasonality and weather conditions, alternative energy sources such as wind, solar and other renewable energy technologies, economic and political conditions domestically and internationally and governmental regulations. Sustained periods of low energy prices could result in producers deciding to limit their oil and gas drilling operations, which could substantially delay the production and delivery of volumes of oil, natural gas and NGLs to our facilities and adversely affect our revenues and cash available for distribution.

This impact may also be exacerbated in circumstances where our compensation for services is commodity-based, which are more directly impacted by changes in natural gas and NGL prices than our fee-based contracts due to frac spread exposure and may result in operating losses when natural gas becomes more expensive on a Btu equivalent basis than NGL products. In addition, our purchase and resale of natural gas and NGLs in the ordinary course exposes us to significant risk of volatility in natural gas or NGL prices due to the potential difference in price at the time of purchase and subsequent sale. The significant volatility in natural gas, NGL and crude oil prices could adversely impact our unit price, thereby increasing our distribution yield and cost of capital. Such impacts could adversely impact our ability to execute our long-term organic growth projects, satisfy our obligations to our customers, and make distributions to unitholders at intended levels, and may also result in non-cash impairments of long-lived assets or goodwill or other-than-temporary non-cash impairments of our equity method investments.

We may not always be able to accurately estimate expected production volumes of our producer customers; therefore, volumes we service in the future could be less than we anticipate.

We may not be able to accurately estimate expected production volumes of our producer customers. Furthermore, we may have only limited crude oil, natural gas, NGL or refined product supplies committed to any new facility prior to its construction. We may

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build new facilities based on expected production growth or market demand. If these expectations are not met, the facilities may be underutilized or may not operate as planned. In order to attract additional crude oil, natural gas, NGL or refined product supplies from a customer, we may be required to order equipment and facilities, obtain rights of way or other land rights or otherwise commence construction activities for facilities that will be required to serve such customer’s additional supplies prior to executing agreements with the customer. If such agreements are not executed, we may be unable to recover such costs and expenses. Additionally, new facilities may not be able to attract enough crude oil, natural gas, NGLs or refined products to achieve our expected investment return. Alternatively, crude oil, natural gas, NGL or refined product supplies committed to facilities under construction may be delivered prior to completion of such facilities. In such event, we may be required to temporarily utilize third-party facilities to offload crude oil, natural gas, NGLs or refined products, which may increase our operating costs and reduce our cash available for distribution.

We depend on third parties for the crude oil, natural gas and refined products we gather, transport and store, the natural gas we process, and the NGLs we fractionate and stabilize at our facilities, and a reduction in these quantities could reduce our revenues and cash flow.

A significant portion of our supply of crude oil, natural gas, NGLs and refined products comes from few key suppliers, who may be under no obligation to deliver a minimum volume. If these or several smaller producers, were to decrease the supply of crude oil, natural gas, NGLs or refined products to our systems and facilities for any reason, we could experience difficulty in replacing those lost volumes. In some cases, the producers or suppliers are responsible for gathering or delivering oil, natural gas, NGLs or refined products to our facilities or we rely on other third parties to deliver volumes to us on behalf of the producers or suppliers. If such producers, suppliers or other third parties are unable, or otherwise fail to, deliver the volumes to our facilities, or if our agreements with any of these third parties terminate or expire such that our facilities are no longer connected to their gathering or transportation systems or the third parties modify the flow of natural gas or NGLs on those systems away from our facilities, the throughput on and utilization of our facilities may be reduced, or we may be required to incur significant capital expenditures to construct and install gathering pipelines or other facilities to be able to receive such volumes. Since most of our operating costs are fixed, a reduction in delivered volumes lowers revenue, net income and cash flow.

We may not be able to retain existing customers, or acquire new customers, which would reduce our revenues and limit our future profitability.

A significant portion of our business comes from a limited number of key customers. The renewal or replacement of existing contracts with our customers at rates sufficient to maintain current revenues and cash flows depends on a number of factors beyond our control, including competition from other gatherers, processors, pipelines and fractionators, and the price of, and demand for, natural gas, NGLs, crude oil and refined products in the markets we serve. Our competitors include large oil, natural gas, refining and petrochemical companies, some of which have greater financial resources, more numerous or greater capacity pipelines, processing and other facilities, greater access to natural gas, crude oil and NGL supplies than we do or other synergies with existing or new customers that we cannot provide. Our competitors may also include our joint venture partners, who in some cases are permitted to compete with us and may have a competitive advantage due to their familiarity with our business arising from our joint venture arrangements, as well as third parties on whom we rely to deliver natural gas, NGLs, crude oil and refined products to our facilities, who may have a competitive advantage due to their ability to modify the flow of natural gas, NGLs, crude oil and refined products on their systems away from our facilities. Additionally, our customers that gather gas through facilities that are not otherwise dedicated to us may develop their own processing and fractionation facilities in lieu of using our services.

As a consequence of the increase in competition in the industry, as well as the volatility of natural gas prices, end-users and utilities are reluctant to enter into long-term purchase contracts. Many customers purchase natural gas from multiple suppliers and can switch providers or even switch to alternative fuels when prices fluctuate. Because we compete with many companies of varying size and resources in the natural gas market, we often rely on price. If management cannot renew contracts or adapt to market changes, our profitability may be impacted.

The fees charged to third parties under our gathering, treating, processing, transmission, transportation, fractionation, stabilization and storage agreements may not escalate sufficiently to cover increases in costs, or the agreements may not be renewed or may be suspended in some circumstances.

Our costs may increase at a rate greater than the fees we charge to third parties. Furthermore, third parties may not renew their contracts with us. Additionally, some third parties’ obligations under their agreements with us may be permanently or temporarily reduced due to certain events, some of which are beyond our control, including force majeure events wherein the supply of natural gas, NGLs, crude oil or refined products are curtailed or cut-off due to events outside our control, and in some cases, certain of those agreements may be terminated in their entirety if the duration of such events exceeds a specified period of time. If the escalation of fees is insufficient to cover increased costs, or if third parties do not renew or extend their contracts with us, or if third parties suspend or terminate their contracts with us, our financial results would suffer.

The U.S. inland waterway infrastructure is aging and may result in increased costs and disruptions to our operations.

Maintenance of the U.S. inland waterway system is vital to our marine transportation operations. The system is composed of over 12,000 miles of commercially navigable waterway, supported by approximately 240 locks and dams designed to provide flood control, maintain pool levels of water in certain areas of the country and facilitate navigation on the inland river system. The U.S. inland waterway infrastructure is aging, with more than half of the locks over 50 years old. As a result, due to the age of the

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locks, planned and unplanned maintenance may create more frequent outages, resulting in delays and additional operating expenses. Part of the costs for new construction and major rehabilitation of locks and dams is funded by marine transportation companies through taxes and the other portion is funded by general federal tax revenues. Failure of the federal government to adequately fund infrastructure maintenance and improvements in the future would have a negative impact on our ability to deliver products to our customers on a timely basis. Furthermore, any additional user taxes that may be imposed in the future to fund infrastructure improvements would increase our operating expenses.

Our operations ar e subject to business interruptions and present inherent hazards and risks, which could adversely impact our results of operations and financial condition.

Our operations are subject to business interruptions, such as unplanned maintenance, explosions, fires, pipeline releases, product quality incidents, power outages, severe weather, labor disputes, acts of terrorism or other natural or man-made disasters. These types of incidents adversely affect us. Our customers’ operations, including MPC’s refining operations, are subject to similar risks.

These types of incidents adversely affect our operations and may result in serious personal injury or loss of human life, significant damage to property and equipment, environmental pollution, impairment of operations and substantial losses. We and our customers have experienced certain of these incidents in the past. For assets located near populated areas, the level of damage resulting from these incidents could be greater. Due to the nature of our operations, certain interruptions could impact operations in other regions.

Our marine transportation business, in particular, is subject to weather conditions. Adverse weather conditions such as high or low water on the inland waterway systems, fog and ice, tropical storms, hurricanes and tsunamis on both the inland waterway systems and throughout the U.S. coastal waters can impair the operating efficiencies of the marine fleet. Such adverse weather conditions can cause a delay, diversion or postponement of shipments of products and are beyond our control.

In addition, we operate in and adjacent to environmentally sensitive waters where tanker, pipeline, rail car and refined product transportation and storage operations are closely regulated by federal, state and local agencies and monitored by environmental interest groups. Transportation and storage of crude oil, other feedstocks and refined products over and adjacent to water involves inherent risk and subjects us to the provisions of the OPA-90 and state laws in U.S. coastal and Great Lakes states and states bordering inland waterways on which we operate. If we are unable to promptly and adequately contain any accident or discharge involving tankers, pipelines, rail cars or above ground storage tanks transporting or storing crude oil, other feedstocks or refined products, we may be subject to substantial liability. In addition, the service providers contracted to aid us in a discharge response may be unavailable due to weather conditions, governmental regulations or other local or global events.

The construction and operation of certain of our facilities may be impacted by surface or subsurface mining operations by one or more third parties, which could adversely impact our construction activities or cause subsidence or other damage to our facilities. In such event, our construction may be prevented or delayed, or the costs and time increased, or our operations at such facilities may be impaired or interrupted, and we may not be able to recover the costs incurred for delays or to relocate or repair our facilities from such third parties.

Damages resulting from an incident involving any of our assets or operations may result in our being named as a defendant in one or more lawsuits asserting potentially substantial claims or in our being assessed potentially substantial fines by governmental authorities.

We may be negatively impacted by inflation.

Increases in inflation may have an adverse effect on us. Such increases in inflation could impact the commodity markets generally, the overall demand for our products and services, our costs for labor, material and services and the margins we are able to realize on our products and services, all of which could have an adverse impact on our business, financial position, results of operations and cash flows. Inflation may also result in higher interest rates, which in turn would result in higher interest expense related to our variable rate indebtedness and any borrowings we undertake to refinance existing fixed rate indebtedness.

We are increasingly dependent on the performance of our information technology systems and those of our third-party business partners and service providers.

We are increasingly dependent on our information technology systems and those of our third-party business partners and service providers for the safe and effective operation of our business. We rely on such systems to process, transmit and store electronic information, including financial records and personal data, and to manage or support a variety of business processes, including our supply chain, pipeline operations, gathering and processing operations, financial transactions, banking and numerous other processes and transactions.

Our information systems (and those of our third-party business partners and service providers), including our cloud computing environments and operational technology environments, are subject to numerous and evolving cybersecurity threats and attacks, including ransomware and other malware, phishing and social engineering schemes, supply chain attacks, and advanced artificial intelligence attacks, which can compromise our ability to operate, and the confidentiality, availability, and integrity of data in our systems or those of our third-party business partners and service providers. These and other cybersecurity threats may

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originate with criminal attackers, advanced persistent threats and nation-state actors, state-sponsored actors, or employee error or malfeasance. Cybersecurity threat actors also may attempt to exploit vulnerabilities in software, including software commonly used by companies in cloud-based services and bundled software. Because the techniques used to obtain unauthorized access, or to disable or degrade systems, continuously evolve and some have become increasingly complex and sophisticated, and can remain undetected for a period of time despite efforts to detect and respond in a timely manner, we (and our third-party business partners and service providers) are subject to the risk of cyberattacks and cybersecurity incidents.

Our cybersecurity and infrastructure protection technologies, disaster recovery plans and systems, employee training and vendor risk management may not be sufficient to defend us against all unauthorized attempts to access our information or impact our systems. We and our third-party vendors and service providers have been and may in the future be subject to cybersecurity events and incidents of varying degrees. To date, the impacts of prior events and incidents have not had a material adverse effect on us.

Cybersecurity incidents involving our information technology systems or those of our third-party business partners and service providers can result in theft, destruction, loss, misappropriation or release of confidential financial data, personal data, intellectual property and other information; give rise to remediation or other expenses; result in litigation, claims and increased regulatory review, investigations, or scrutiny; reduce our customers’ willingness to do business with us; disrupt our operations and the services we provide to customers; and subject us to litigation and legal liability under international, U.S. federal and state laws. Any of such results could have a material adverse effect on our reputation, business, financial condition, results of operations and cash flows.

Increasing regulatory focus on and expanding laws related to data privacy issues could expose us to increased liability, subject us to lawsuits, investigations, reputational harm and increase costs and restrictions on our operations that could significantly and adversely affect our business.

Along with our own data and information collected in the normal course of our business, we, and some of our third-party service providers, collect, use, transfer and retain certain data that is subject to specific laws and regulations. The transfer and use of this data is becoming increasingly complex. This data is subject to governmental regulation at international, federal, state and local levels in many areas of our business, including data privacy and security laws such as the California Consumer Privacy Act, as amended by the California Privacy Rights Act (“CCPA”). To date, comprehensive state privacy laws have been proposed or passed in more than twenty U.S. states. Additionally, the U.S. Federal Trade Commission and multiple state attorneys general are interpreting federal and state consumer protection laws to impose standards for the online collection, use, dissemination and security of data as well as requiring disclosures regarding such practices. Existing and potential future data privacy laws pose increasingly complex compliance, monitoring and control obligations and could potentially elevate our costs and risk exposure. As the implementation, interpretation, and enforcement of such laws continue to progress and evolve, there may also be developments that amplify such costs and risk exposure. Any failure by us, or by a third-party service provider upon which we rely, to comply with these laws and regulations, including as a result of a cybersecurity incident or privacy breach, could expose us to significant penalties and liabilities, including individual claims or consumer class actions, commercial litigation, administrative, and investigations or actions, regulatory intervention and sanctions or fines.

As we integrate artificial intelligence technologies into our processes, these technologies may present business, compliance and reputational risks.

Recent and continuously evolving technological advances in artificial intelligence (“AI”) and machine-learning technology present new opportunities and also pose new risks. Our integration of these technologies, whether developed internally or procured through our third-party service providers, into our processes may result in new or expanded risks and liabilities. Such risks and liabilities include enhanced governmental or regulatory scrutiny, litigation, compliance issues, ethical concerns, confidentiality or security risks, as well as other factors that could adversely affect our business, reputation, and financial results. The utilization of AI could also result in loss of intellectual property and subject us to heightened risks related to intellectual property infringement or misappropriation. The use of AI can lead to unintended consequences, including generating content that is inaccurate, misleading or otherwise flawed, or that results in unintended biases and discriminatory outcomes, which could harm our reputation and expose us to risks related to inaccuracies or errors in the output of such technologies.

Our investments in joint ventures could be adversely affected by our reliance on our joint venture partners and their financial condition, and our joint venture partners may have interests or goals that are inconsistent with ours.

We conduct some of our operations through joint ventures in which we share control over certain economic and business interests with our joint venture partners. Our joint venture partners may have economic, business or legal interests or goals that are inconsistent with our goals and interests or may be unable to meet their obligations. Failure by us, or an entity in which we have an interest, to adequately manage the risks associated with any joint ventures could have a material adverse effect on the financial condition or results of operations of our joint ventures and adversely affect our reputation, business, financial condition, results of operations and cash flows.

Terrorist attacks or other targeted operational disruptions may affect our facilities or those of our customers and suppliers.

Refining, gathering and processing, pipeline and terminal infrastructure, and other energy assets, may be the subject of terrorist attacks or other targeted operational disruptions. Any attack or targeted disruption of our operations, those of our customers or, in

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some cases, those of other energy industry participants, could have a material and adverse effect on our business. Similarly, any similar event that severely disrupts the markets we serve could materially and adversely affect our results of operations, financial position and cash flows.

Many of our assets have been in service for many years and, as a result, our maintenance or repair costs may increase in the future.

Our pipelines, terminals, fractionators, processing facilities and storage assets are generally long-lived assets, and many of them have been in service for many years. The age and condition of our assets could result in increased maintenance or repair expenditures in the future. Any significant increase in these expenditures could adversely affect our results of operations, financial position or cash flows, as well as our ability to make cash distributions to our unitholders.

Severe weather events, other climate conditions and earth movement and other geological hazards may adversely affect our and our customers’ assets and ongoing operations.

Our and our customers’ assets are subject to acute physical risks, such as floods, hurricane-force winds, wildfires, winter storms, and earth movement in variable, steep and rugged terrain and terrain with varied or changing subsurface conditions, and chronic physical risks, such as sea-level rise or water shortages. The occurrence of these and similar events have had, and may in the future have, an adverse effect on our assets and operations. We have incurred and will continue to incur additional costs to protect our assets and operations from such physical risks and employ the evolving technologies and processes available to mitigate such risks. To the extent such severe weather events or other climate conditions increase in frequency and severity, we may be required to modify operations and incur costs that could materially and adversely affect our business, financial condition, results of operations and cash flows.

Financial Risks

We may not have sufficient cash from operations after the establishment of cash reserves and payment of our expenses, including cost reimbursements to MPC and its affiliates, to enable us to pay the intended quarterly distribution to our unitholders.

The amount of cash we can distribute to our common unitholders principally depends on the amount of cash we generate from our operations, which fluctuates from quarter to quarter based on, among other things:

• the volumes of natural gas, crude oil, NGLs and refined products we gather, process, store, transport and fractionate;

• the fees and tariff rates we charge and the margins we realize for our services and sales;

• the prices of, level of production of and demand for crude oil, natural gas, NGLs and refined products;

• the level of our operating costs including repairs and maintenance;

• the relative prices of NGLs and crude oil; and

• prevailing economic conditions.

In addition, the actual amount of cash available for distribution also depends on other factors, some of which are beyond our control, including:

• the amount of our operating expenses and general and administrative expenses, including cost reimbursements to MPC;

• our debt service requirements and other liabilities;

• fluctuations in our working capital needs;

• our ability to borrow funds and access capital markets;

• restrictions in our joint venture agreements or agreements governing our debt;

• the level and timing of capital expenditures we make, including capital expenditures incurred in connection with our growth projects;

• the cost of acquisitions, if any; and

• the amount of cash reserves established by our general partner in its discretion, which may increase in the future and which may in turn further reduce the amount of cash available for distribution.

Furthermore, the amount of cash we have available for distribution depends primarily on our cash flow and not solely on profitability, which is affected by non-cash items. As a result, we may make distributions during periods when we record net losses and may not make distributions during periods when we record net income.

Our substantial debt and other financial obligations could impair our financial condition, results of operations and cash flow, and our ability to fulfill our debt obligations.

We have significant debt obligations, which totaled $26.0 billion as of December 31, 2025, including amounts, if any, outstanding under our loan agreement with MPC. We may incur significant debt obligations in the future. Our indebtedness may impose

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various restrictions and covenants on us that could have, or the incurrence of such debt could otherwise result in, material adverse consequences, including:

• We may have difficulties obtaining additional financing for working capital, capital expenditures, acquisitions, or general business purposes on favorable terms, if at all, or our cost of borrowing may increase.

• We may be at a competitive disadvantage compared to our competitors who have proportionately less debt, or we may be more vulnerable to, and have limited flexibility to respond to, competitive pressures or a downturn in our business or the economy generally.

• If our operating results are not sufficient to service our indebtedness, we may be required to reduce our distributions, reduce or delay our business activities, investments or capital expenditures, sell assets or issue equity, which could materially and adversely affect our financial condition, results of operations, cash flows and ability to make distributions to unitholders, as well as the trading price of our common units.

• The operating and financial restrictions and covenants in our revolving credit facility and any future financing agreements could restrict our ability to finance our operations or capital needs or to expand or pursue our business activities, which may, in turn, limit our ability to make distributions to our unitholders. Our ability to comply with these covenants may be impaired from time to time if the fluctuations in our working capital needs are not consistent with the timing for our receipt of funds from our operations.

• If we fail to comply with our debt obligations and an event of default occurs, our lenders could declare the outstanding principal of that debt, together with accrued interest, to be immediately due and payable, which may trigger defaults under our other debt instruments or other contracts. Our assets may be insufficient to repay such debt in full, and the holders of our units could experience a partial or total loss of their investment.

Increases in interest rates could adversely impact our unit price, our ability to issue equity or incur additional debt for acquisitions or other purposes or refinance existing debt and our ability to make distributions at our intended levels.

Our revolving credit facility and our loan agreement with MPC have variable interest rates. As a result, future interest rates on our debt could be higher than current levels, causing our financing costs to increase accordingly. In addition, we may in the future refinance outstanding borrowings under our revolving credit facility with fixed-rate indebtedness. Interest rates payable on fixed-rate indebtedness typically are higher than the short-term variable interest rates that we pay on borrowings under our revolving credit facility. We also have other fixed-rate indebtedness that we may need or desire to refinance in the future at or prior to the applicable stated maturity. A prolonged rising interest rate environment could have an adverse impact on our ability to issue equity, refinance existing debt or incur additional debt for acquisitions or other purposes on favorable terms, if at all. Accordingly, increases in interest rates could adversely impact our business, financial conditions, results of operations, cash flows and our ability to make distributions at our intended levels.

As with other yield-oriented securities, our unit price will be impacted by our cash distributions and the implied distribution yield. The distribution yield is often used by investors to compare and rank yield-oriented securities for investment decision-making purposes. Therefore, changes in interest rates, either positive or negative, may affect the yield requirements of investors who invest in our units, and a rising interest rate environment could have an adverse impact on our unit price.

We are exposed to the credit risks of our key customers, and any material non-payment or non-performance by our key customers could reduce our ability to make distributions to our unitholders.

We are subject to risks of loss resulting from non-payment or non-performance by our customers, which risks may increase during periods of economic uncertainty. Furthermore, some of our customers may be highly leveraged and subject to their own operating and regulatory risks, which increases the risk that they may default on their obligations to us. This risk is further heightened during sustained periods of declines of natural gas, NGL and crude oil prices. To the extent any of our customers are in financial distress or commence bankruptcy proceedings, our contracts with them, including provisions relating to dedications of production, may be subject to renegotiation or rejection under applicable provisions of the United States Bankruptcy Code. If a contract with a customer is altered or rejected in bankruptcy proceedings, we could lose some or all of the expected revenues associated with that contract. Any such material non-payment or non-performance could have a material adverse effect on our business, financial condition, results of operations and cash flows.

We do not insure against all potential losses, and, therefore, our business, financial condition, results of operations and cash flows could be adversely affected by unexpected liabilities and increased costs.

We maintain insurance coverage in amounts we believe to be prudent against many, but not all, potential liabilities arising from operating hazards. Uninsured liabilities arising from operating hazards such as explosions, fires, pipeline releases, cybersecurity breaches or other incidents involving our assets or operations can reduce the funds available to us for capital and investment spending and could have a material adverse effect on our business, financial condition, results of operations and cash flows. Historically, we also have maintained insurance coverage for physical damage and resulting business interruption to our major facilities, with significant self-insured retentions. In the future, we may not be able to maintain insurance of the types and amounts we desire at reasonable rates.

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We have recorded goodwill and other intangible assets that could become further impaired and result in material non-cash charges to our results of operations.

We accounted for certain acquisitions using the acquisition method of accounting, which requires that the assets and liabilities of the acquired business be recorded to our balance sheet at their respective fair values as of the acquisition date. Any excess of the purchase consideration over the fair value of the acquired net assets is recognized as goodwill.

As of December 31, 2025, our balance sheet reflected $8.8 billion and $1.4 billion of goodwill and other intangible assets, respectively. We have in the past recorded significant impairments of our goodwill. To the extent the value of goodwill or intangible assets becomes further impaired, we may be required to incur additional material non-cash charges relating to such impairment. Our operating results may be significantly impacted from both the impairment and the underlying trends in the business that triggered the impairment.

Large capital projects may be subject to delays, can take years to complete, and market conditions could deteriorate significantly between the project approval date and the project startup date, negatively impacting project returns.

Delays in completing capital projects or making required changes or upgrades to our facilities could subject us to fines or penalties as well as affect our ability to supply certain products we produce. Such delays or cost increases may arise as a result of unpredictable factors, many of which are beyond our control, including:

• denials of, delays in receiving, or revocations of requisite regulatory approvals or permits;

• unplanned increases in the cost of construction materials or labor, whether due to inflation or other factors;

• disruptions in transportation of components or construction materials;

• adverse weather conditions, natural disasters or other events (such as equipment malfunctions, explosions, fires or spills) affecting our facilities, or those of vendors or suppliers;

• shortages of sufficiently skilled labor, or labor disagreements resulting in unplanned work stoppages;

• market-related increases in a project’s debt or equity financing costs;

• global supply chain disruptions;

• nonperformance by, or disputes with, vendors, suppliers, contractors or subcontractors; and

• delays due to citizen, state or local political or activist pressure.

Any one or more of these factors could have a significant impact on our ongoing capital projects. If we were unable to make up the delays associated with such factors or to recover the related costs, or if market conditions change, it could materially and adversely affect our capital project returns and our business, financial condition, results of operations and cash flows.

Legal and Regulatory Risks

We expect to continue to incur substantial capital expenditures and operating costs to meet the requirements of evolving environmental and other laws or regulations. Changes to the federal government’s policies and operations could lead to increased regulatory uncertainty and volatility and increased state regulation, which may impact our business, financial condition and results of operations.

Our business is subject to numerous environmental laws and regulations at the federal, state and local level. These laws and regulations continue to increase in both number and complexity and affect our business. Laws and regulations expected to become more stringent relate to the following:

• the emission or discharge of materials into the environment;

• solid and hazardous waste management;

• the regulatory classification of materials currently or formerly used in our business;

• pollution prevention;

• climate change and GHG emissions;

• the production, importation, use, and disposal of specific chemicals;

• public and employee safety and health;

• permitting;

• inherently safer technology; and

• facility security.

The specific impact of laws and regulations on us and our competitors may vary depending on a number of factors, including the age and location of operating facilities, marketing areas and production processes and subsequent judicial interpretation of such laws and regulations. We have incurred and will continue to incur substantial capital, operating and maintenance, and remediation expenditures to modify operations, install pollution control equipment, perform site cleanups or curtail operations. We have incurred and may in the future incur liability for personal injury, property damage, natural resource damage or clean-up costs due to alleged contamination and/or exposure to chemicals such as benzene and methyl tert-butyl ether (“MTBE”). There is also increased regulatory interest in PFAS, which we expect will lead to increased monitoring and remediation obligations and

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potential liability related thereto. Such expenditures could materially and adversely affect our business, financial condition, results of operations and cash flows.

In 2025, the U.S. presidential administration announced wide-ranging policy changes and issued numerous executive actions. The U.S. EPA and other federal agencies began proposing and promulgating regulations consistent with the administration’s policy changes. If the federal government relaxes or revokes certain environmental regulations, states may pass laws that vary in stringency and scope by state, creating a patchwork of regulation. For example, various states have passed laws regulating the use of materials containing PFAS and setting action levels for the remediation of certain PFAS. We cannot predict the extent to which states will pass such legislation, or the ultimate effect these state laws will have on our business, financial condition and results of operations.

Increased regulation of hydraulic fracturing and other oil and gas production activities could result in reductions or delays in U.S. production of crude oil and natural gas, which could adversely affect our results of operations and financial condition.

While we do not conduct hydraulic fracturing operations, we do provide gathering, treating, processing and fractionation services with respect to natural gas and natural gas liquids produced by our customers as a result of such operations. A range of federal, state and local laws and regulations currently govern or, in some cases, prohibit, hydraulic fracturing in some jurisdictions. Stricter laws, regulations and permitting processes may be enacted in the future. If federal, state and local legislation and regulatory initiatives relating to hydraulic fracturing or other oil and gas production activities are enacted or expanded, such efforts could impede oil and gas production, increase producers’ cost of compliance, and result in reduced volumes available for our midstream assets to gather, treat, process and fractionate.

Climate change and GHG emission regulation could affect our operations, energy consumption patterns and regulatory obligations, any of which could adversely impact our business, results of operations and financial condition.

Currently, multiple legislative and regulatory measures to address GHG and other emissions are in various phases of consideration, promulgation or implementation. These include actions to develop international, federal, regional or statewide programs, which could require reductions in our GHG or other emissions, establish a carbon tax and decrease the demand for refined products. Requiring reductions in these emissions could result in increased costs to (i) operate and maintain our facilities, (ii) install new emission controls at our facilities and (iii) administer and manage any emissions programs, including acquiring emission credits or allotments.

Certain municipalities have also proposed or enacted restrictions on the installation of natural gas appliances and infrastructure in new residential or commercial construction, which could affect demand for the natural gas that we transport and store. Certain jurisdictions have enacted or are considering ordinances that would prohibit construction or expansion of fossil fuel terminals.

Regional and state climate change and air emissions goals and regulatory programs are complex, subject to change and considerable uncertainty due to a number of factors including technological feasibility, legal challenges and potential changes in federal policy. Increasing concerns about climate change and carbon intensity have also resulted in societal concerns and a number of international and national measures to limit GHG emissions. Additional stricter measures and investor pressure can be expected in the future and any of these changes may have a material adverse impact on our business or financial condition.

The scope and magnitude of the changes to U.S. climate change strategy under the current and future administrations, however, remain subject to the passage of legislation and interpretation and action of federal and state regulatory bodies; therefore, the impact to our industry and operations due to GHG regulation is unknown at this time.

Energy companies are subject to increasing environmental and climate-related litigation.

Governmental and other entities in various U.S. states have filed lawsuits against various energy companies, including MPC, alleging damages as a result of climate change, false statements about climate change, and violations of various consumer protection statutes. The plaintiffs are seeking unspecified damages and abatement under various tort theories.

Additionally, private plaintiffs and government parties have undertaken efforts to shut down energy assets by challenging operating permits, the validity of easements or the compliance with easement conditions. For example, the Dakota Access Pipeline, in which we have a minority interest, is subject to, and may in the future be subject to, litigation seeking a permanent shutdown of the pipeline. There remains a high degree of uncertainty regarding the ultimate outcome of these types of proceedings, as well as their potential effect on our business, financial condition, results of operation and cash flows.

We are subject to risks associated with societal and political pressures and other forms of opposition to the development, transportation and use of carbon-based fuels. Such risks could adversely impact our business and our ability to continue to operate or realize certain growth strategies.

We operate and develop our business with the expectation that regulations and societal sentiment will continue to enable the development, transportation and use of carbon-based fuels. However, policy decisions relating to the production, refining, transportation, storage and marketing of carbon-based fuels are subject to political pressures and the influence of public sentiment on GHG emissions, climate change, and climate adaptation. Additionally, societal sentiment regarding carbon-based fuels may adversely impact our reputation and MPC’s ability to attract and retain the employees who provide services to us.

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The approval process for our projects has become increasingly challenging, due in part to state and local concerns related to pipelines, negative public perception regarding the oil and gas industry, and concerns regarding GHG emissions downstream of pipeline operations. Our expansion or construction projects may not be completed on schedule (or at all), or at the budgeted cost. We also may be required to incur additional costs and expenses in connection with the design and installation of our facilities due to their location and the surrounding terrain. We may be required to install additional facilities, incur additional capital and operating expenditures, or experience interruptions in or impairments of our operations to the extent that the facilities are not designed or installed correctly.

Increasing attention to environmental, social and governance matters may impact our business and financial results.

In recent years, increasing attention has been given to corporate activities related to ESG matters in public discourse and the investment community, including climate change, energy transition matters, and inclusion. A number of advocacy groups, both domestically and internationally, have campaigned for governmental and private action to promote ESG-related change at public companies, including, but not limited to, through the investment and voting practices of investment advisers, pension funds, universities and other members of the investing community. These activities include increasing attention and demands for action related to climate change and energy transition matters, such as promoting the use of substitutes to fossil fuel products and encouraging the divestment of fossil fuel equities, as well as pressuring lenders and other financial services companies to limit or curtail activities with fossil fuel companies. If this were to continue, it could have a material adverse effect on our access to capital. Members of the investment community have begun to screen companies such as ours for sustainability performance, including practices related to GHG emission reduction and energy transition strategies. If we are unable to find economically viable, as well as publicly acceptable, solutions that reduce our GHG emissions, reduce GHG intensity for new and existing projects, increase our non-fossil fuel product portfolio, and/or address other ESG-related stakeholder concerns, our business and results of operations could be materially and adversely affected. Further, our reputation could be damaged as a result of our support of, association with or lack of support or disapproval of certain social causes, as well as any decisions we make to continue to conduct, or change, certain of our activities in response to such considerations.

Our goals, targets and disclosures related to ESG matters expose us to numerous risks, including risks to our reputation and unit price.

Companies across all industries are facing increasing scrutiny from stakeholders related to ESG matters, including practices and disclosures regarding climate-related initiatives. MPLX has established a target to reduce methane emissions intensity and MPC, MPLX’s largest customer, has established a target to reduce GHG emissions intensity. These targets reflect our current plans and aspirations and are not guarantees that we will be able to achieve them. We assess progress with these targets on an annual basis. We may modify, discontinue, update or expand targets or adopt new metrics as new information, opportunities, and technologies become available. Further, there are conflicting expectations and priorities from regulatory authorities, investors, voluntary reporting frame works, and other stakeholders surrounding accounting and disclosure of ESG matters and climate related initiatives. Our efforts to accomplish and accurately report on these goals and objectives, which may be, in part, dependent on the actions of suppliers and other third parties, present numerous operational, regulatory, reputational, financial, legal, and other risks, any of which could have a material negative impact, including on our reputation and unit price.

Efforts to achieve goals and targets, such as the foregoing and future internal climate-related initiatives, may increase costs, require purchase of carbon credits, or limit or impact our business plans and financial results, potentially resulting in the reduction to the economic end-of-life of certain assets and an impairment of the associated net book value, among other material adverse impacts. Additionally, as the nature, scope and complexity of ESG reporting, calculation methodologies, voluntary reporting standards and disclosure requirements expand, we may have to undertake additional costs to control, assess and report on ESG metrics. Our failure or perceived failure to pursue or fulfill such goals and targets or to satisfy various reporting standards within the timelines we announce, or at all, could have a negative impact on investor sentiment, ratings outcomes for evaluating our approach to ESG matters, unit price, and cost of capital and expose us to government enforcement actions and private litigation, among other material adverse impacts.

Certain of our facilities are located on Native American tribal lands and are subject to various federal and tribal approvals and regulations, which can increase our costs and delay or prevent our efforts to conduct operations.

Various federal agencies within the U.S. Department of the Interior, particularly the Bureau of Indian Affairs, along with each Native American tribe, regulate natural gas and oil operations on Native American tribal lands. In addition, each Native American tribe is a sovereign nation having the right to enforce laws and regulations and to grant approvals independent from federal, state and local statutes and regulations. These tribal laws and regulations include various taxes, fees, requirements to employ Native American tribal members and other conditions that apply to operators and contractors conducting operations on Native American tribal lands. Persons conducting operations on tribal lands are generally subject to the Native American tribal court system. In addition, if our relationships with any of the relevant Native American tribes were to deteriorate, we could face significant risks to our ability to continue operations on Native American tribal lands. One or more of these factors has in the past and may in the future increase our cost of doing business on Native American tribal lands and impact the viability of, or prevent or delay our ability to conduct our operations on such lands. For example, we are subject to ongoing litigation regarding trespass claims relating to a portion of the Tesoro High Plains Pipeline in North Dakota.

Our operations could be disrupted if we are unable to maintain or obtain real property rights required for our business.

We do not own all of the land on which our assets are located, but rather obtain the rights to construct and operate such assets on land owned by third parties and governmental agencies for a specific period of time. Therefore, we are subject to the

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possibility of more burdensome terms and increased costs to obtain and retain necessary land use if our leases, rights-of-way or other property rights lapse, terminate or are reduced or it is determined that we do not have valid leases, rights-of-way or other property rights. For example, a portion of the Tesoro High Plains Pipeline in North Dakota remains shut down following delays in renewing a right-of-way necessary for the operation of a section of the pipeline. Any loss of or reduction in these rights, including loss or reduction due to legal, governmental or other actions or difficulty renewing leases, right-of-way agreements or permits on satisfactory terms or at all, could have a material adverse effect on our business, results of operations, financial condition and ability to make cash distributions to our unitholders.

If foreign investment in us or our general partner exceeds certain levels, we could be prohibited from operating inland river vessels, which could materially and adversely affect our business, financial condition, results of operations and cash flows.

The Shipping Act of 1916 and Merchant Marine Act of 1920 (together, the “Maritime Laws”), generally require that vessels engaged in U.S. coastwise trade be owned by U.S. citizens. Among other requirements to establish citizenship, entities that own such vessels must be owned at least 75 percent by U.S. citizens. If we fail to maintain compliance with the Maritime Laws, we would be prohibited from operating vessels in the U.S. inland waters. Such a prohibition could materially and adversely affect our business, financial condition, results of operations and cash flows.

Some of our natural gas, NGL, crude oil and refined product pipelines are subject to FERC’s rate-making policies that could have an adverse impact on our ability to establish rates that would allow us to recover the full cost of operating our pipelines, plus a reasonable return.

A number of our pipelines provide interstate service that is subject to regulation by FERC. FERC prescribes rate methodologies for developing regulated tariff rates for these natural gas, interstate oil and products pipelines. FERC’s regulated tariff may not allow us to recover all of our costs of providing services. Changes in FERC’s approved rate methodologies, or challenges to our application of an approved methodology, could also adversely affect our rates. Additionally, shippers may protest (and FERC may investigate) the lawfulness of tariff rates. FERC can require refunds of amounts collected pursuant to rates that are ultimately found to be unlawful and prescribe new rates prospectively. Action by FERC could adversely affect our ability to establish reasonable rates that cover operating costs and allow for a reasonable return. An adverse determination in any future rate proceeding brought by or against us could have a material adverse effect on our business, financial condition and results of operations.

Pipelines and operations not subject to regulation by FERC may still be subject to regulation by various state agencies. The applicable statutes and regulations generally require that our rates and terms and conditions of service provide no more than a fair return on the aggregate value of the facilities used to render services and that we offer service to our shippers on a not unduly discriminatory basis. FERC rate cases can involve complex and expensive proceedings. For more information regarding regulatory matters that could affect our business, please read Item 1. Business – Regulatory Matters as set forth in this Annual Report on Form 10-K.

We may incur significant costs and liabilities resulting from performance of pipeline integrity programs and related repairs, and the expansion of pipeline safety laws and regulations could require us to use more comprehensive and stringent safety controls and subject us to increased capital and operating costs.

The DOT through the PHMSA has adopted regulations requiring pipeline operators to develop integrity management programs for gas transmission and hazardous liquids pipelines located where a leak or rupture could do the most harm. The regulations require the following of operators of covered pipelines to:

• perform ongoing assessments of pipeline integrity;

• identify and characterize applicable threats to pipeline segments that could impact a high consequence area;

• improve data collection, integration and analysis;

• repair and remediate the pipeline as necessary; and

• implement preventive and mitigating actions.

Some states have adopted regulations similar to existing PHMSA regulations for intrastate gathering and transmission lines. The adoption of additional laws or regulations that apply more comprehensive or stringent safety standards to gas, NGL, crude oil and refined product lines or other facilities, or the expansion of regulatory inspections by regulators, could require us to install new or modified safety controls, pursue added capital projects, make modifications or operational changes, or conduct maintenance programs on an accelerated basis, all of which could require us to incur increased capital and operational costs or operational delays that could be significant and have a material adverse effect on our business, financial position, results of operations, cash flows and our ability to make distributions to our unitholders.

Transaction Risks

If we are unable to make strategic acquisitions on economically acceptable terms from MPC or third parties, our ability to implement our business strategy may be impaired.

In addition to organic growth, a component of our business strategy can include the expansion of our operations through strategic acquisitions. If we are unable to make accretive strategic acquisitions from MPC or third parties that increase the cash

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generated from operations per unit, whether due to an inability to identify attractive acquisition candidates, to negotiate acceptable purchase contracts, or to obtain financing for these acquisitions on economically acceptable terms, then our ability to successfully implement our business strategy may be impaired.

Significant acquisitions, including the Northwind Midstream Acquisition and the BANGL Acquisition, will involve the integration of new assets or businesses and may present substantial risks that could adversely affect our business, financial conditions, results of operations and cash flows.

Significant acquisitions, including the Northwind Midstream Acquisition and the BANGL Acquisition, involving the addition of new assets or businesses will present risks, which may include, among others:

• inaccurate assumptions about future synergies, revenues, capital expenditures and operating costs;

• an inability to successfully integrate, or a delay in the successful integration of, assets or businesses we acquire;

• a decrease in our liquidity resulting from using a portion of our available cash or borrowing capacity under our revolving credit agreement to finance transactions;

• a significant increase in our interest expense or financial leverage if we incur additional debt to finance transactions;

• the assumption of unknown environmental and other liabilities, losses or costs for which we are not indemnified or for which our indemnity is inadequate;

• the diversion of management’s attention from other business concerns;

• the loss of customers or key employees from the acquired businesses; and

• the incurrence of other significant charges, such as impairment of goodwill or other intangible assets, asset devaluation or restructuring charges.

Risks Relating to the Business and Operations of MPC

MPC accounts for a substantial portion of our revenues. If MPC is unable to satisfy its obligations to us or significantly reduces the volumes transported through our facilities or stored at our storage assets, our revenues would decline and our financial condition, results of operations, cash flows, and ability to make distributions to our unitholders would be materially and adversely affected.

We derive a substantial portion of our revenues from MPC. Any event that materially and adversely affects MPC’s financial condition, results of operations or cash flows may adversely affect our ability to sustain or increase distributions to our unitholders. Accordingly, we are indirectly subject to the operational and business decisions and risks of MPC, which include the following:

• the timing and extent of changes in commodity prices and demand for MPC’s products, and the availability and costs of crude oil and other refinery feedstocks;

• a material decrease in the refining margins at MPC’s refineries;

• disruptions due to equipment interruption or failure at MPC’s facilities or at third-party facilities on which MPC’s business is dependent;

• any decision by MPC to temporarily or permanently alter, curtail or shut down operations at one or more of its refineries or other facilities and reduce or terminate its obligations under our transportation and storage or refining logistics and fuels distribution agreements;

• changes to the routing of volumes shipped by MPC on our crude oil and refined product pipelines or the ability of MPC to utilize third-party pipeline connections to access our pipelines;

• MPC’s ability to remain in compliance with the terms of its outstanding indebtedness;

• changes in the cost or availability of third-party pipelines, railways, vessels, terminals and other means of delivering and transporting crude oil, feedstocks, refined products, other hydrocarbon-based products and renewables;

• state and federal environmental, economic, health and safety, energy and other policies and regulations, and any changes in those policies and regulations;

• imposition of new economic sanctions against Russia or other countries and the effects of potential responsive countermeasures;

• environmental incidents and violations and related remediation costs, fines and other liabilities;

• operational hazards and other incidents at MPC’s refineries and other facilities, such as explosions and fires, that result in temporary or permanent shut downs of those refineries and facilities;

• changes in crude oil and refined product inventory levels and carrying costs; and

• disruptions due to hurricanes, tornadoes or other forces of nature.

MPC is not obligated to use our services with respect to volumes in excess of the minimum volume commitments under its agreements with us. If MPC satisfies only its minimum obligations under, or if we are unable to renew or extend, the transportation, terminal, fuels distribution, marketing and storage services agreements we have with MPC, or if MPC elects to

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use credits upon the expiration or termination of an agreement, our cash available for distribution will be materially and adversely affected.

In addition, significant stockholders of MPC may attempt to effect changes at MPC or acquire control of the company, which could impact MPC’s business strategies. Campaigns by stockholders to effect changes at publicly traded companies are sometimes led by investors seeking to increase short-term stockholder value through actions such as financial restructuring, increased debt, special dividends, stock repurchases or sales of assets or the entire company. As a result, stockholder campaigns at MPC could directly or indirectly adversely affect our results of operations and financial condition and our ability to sustain or increase distributions to our unitholders.

MPC may suspend, reduce or terminate its obligations under its agreements with us in some circumstances, which could have a material adverse effect on our financial condition, results of operations, cash flows and ability to make distributions to our unitholders.

Certain of our transportation, terminal, fuels distribution, marketing and storage services agreements with MPC include provisions that permit MPC to suspend, reduce or terminate its obligations under the applicable agreement if certain events occur. These events include a material breach of the applicable agreement by us, MPC being prevented from transporting its full minimum volume commitment because of capacity constraints on our pipelines, certain force majeure events that would prevent us from performing some or all of the required services under the applicable agreement and MPC’s determination to suspend refining operations at one of its refineries. MPC has the discretion to make such decisions notwithstanding the fact that they may significantly and adversely affect us. These actions could result in a suspension, reduction or termination of MPC’s obligations under one or more transportation and storage services agreements.

Any such reduction, suspension or termination of MPC’s obligations could have a material adverse effect on our financial condition, results of operations, cash flows and ability to make distributions to our unitholders.

MPC’s level of indebtedness, the terms of its borrowings and its credit ratings could adversely affect our ability to grow our business and our ability to make distributions to our unitholders. Our ability to obtain credit in the future may also be adversely affected by MPC’s credit rating.

MPC must devote a portion of its cash flows from operating activities to service its indebtedness, and therefore, cash flows may not be available for use in pursuing its growth strategy. Furthermore, a higher level of indebtedness at MPC in the future increases the risk that it may default on its obligations to us under our transportation and storage services agreements. As of December 31, 2025, MPC had consolidated long-term indebtedness of approximately $33.3 billion, of which $7.3 billion was a direct obligation of MPC or its subsidiaries other than MPLX or its consolidated subsidiaries. The covenants contained in the agreements governing MPC’s outstanding and future indebtedness may limit its ability to borrow additional funds for development and make certain investments and may directly or indirectly impact our operations in a similar manner.

Furthermore, if MPC were to default under certain of its debt obligations, there is a risk that MPC’s creditors would attempt to assert claims against our assets during the litigation of their claims against MPC. The defense of any such claims could be costly and could materially impact our financial condition, even absent any adverse determination. If these claims were successful, our ability to meet our obligations to our creditors, make distributions and finance our operations could be materially and adversely affected.

Rating agencies have in the past, and may in the future, change MPLX’s credit ratings or credit outlook following developments at MPC. If these ratings are lowered in the future, the interest rate and fees MPC pays on its credit facilities may increase. Credit rating agencies will likely consider MPC’s debt ratings when assigning ours because of MPC’s ownership interest in us, the significant commercial relationships between MPC and us, and our reliance on MPC for a portion of our revenues. If one or more credit rating agencies were to downgrade the outstanding indebtedness of us or MPC, we could experience an increase in our borrowing costs or difficulty accessing the capital markets. Such a development could adversely affect our business, financial positions, results of operations, cash flows and our ability to make distributions to our unitholders.

Tax Risks

Our tax treatment depends on our status as a partnership for federal income tax purposes as well as our not being subject to a material amount of entity level taxation by individual states. If the IRS were to treat us as a corporation for federal income tax purposes, or we become subject to a material amount of entity level taxation for state tax purposes, it would substantially reduce the amount of cash available for distribution to our unitholders.

The anticipated after-tax economic benefit of an investment in our common units depends largely on our being treated as a partnership for federal income tax purposes. We have not requested, and do not plan to request, a ruling from the IRS on this.

A publicly traded partnership such as us may be treated as a corporation for federal income tax purposes unless it satisfies a “qualifying income” requirement. Based on our current operations, we believe that we are treated as a partnership rather than as a corporation for such purposes; however, a change in our business or a change in current law could cause us to be treated as a corporation for federal income tax purposes. The IRS may adopt positions that differ from the ones we take. A successful IRS contest of the federal income tax positions we take may adversely impact the market for our common units, and the costs of any IRS contest will reduce our cash available for distribution to unitholders.

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If we were treated as a corporation for federal income tax purposes, we would pay federal income tax on our taxable income at the corporate tax rate, which is currently a maximum of 21 percent, and likely would pay state and local income tax at varying rates. Distributions to unitholders generally would be taxed again as corporate dividends, and no income, gains, losses, deductions, or credits would flow through to our unitholders. Treatment of us as a corporation would result in a material reduction in the anticipated cash flow and after-tax return to our unitholders, likely causing a substantial reduction in the value of our common units. Changes in current state or local law may subject us to additional entity-level taxation by individual states and localities. For example, we are currently subject to state and local taxes in Texas and Tennessee and certain localities in Kentucky, Michigan and Ohio. Imposition of any such additional taxes on us may substantially reduce the cash available for distribution to unitholders.

Our Partnership Agreement provides that, if a law is enacted or an existing law is modified or interpreted in a manner that subjects us to taxation as a corporation or otherwise subjects us to entity-level taxation for federal, state or local income tax purposes, the minimum quarterly distribution amount and the target distribution amounts may be adjusted to reflect the impact of that law on us.

If the IRS contests the federal income tax positions we take, the market for our common units may be adversely impacted and the cost of any IRS contest will reduce our cash available for distribution.

The IRS has made no determination as to our status as a partnership for federal income tax purposes. The IRS may adopt positions that differ from the positions we take. It may be necessary to resort to administrative or court proceedings to sustain some or all the positions we take. A court may not agree with some or all of the positions we take. Any contest with the IRS may materially and adversely impact the market for our common units and the price at which they trade. In addition, our costs of any contest with the IRS will be borne indirectly by our unitholders and our general partner because the costs will reduce our cash available for distribution.

Our unitholders will be required to pay taxes on their share of income even if they do not receive any distributions from us.

Because our unitholders will be treated as partners to whom we will allocate taxable income that could be different in amount than the cash we distribute, our unitholders will be required to pay any federal income taxes and, in some cases, state and local income taxes on their share of our taxable income even if they receive no distributions from us. Our unitholders may not receive distributions from us equal to their share of our taxable income or even equal to the actual tax liability that result from that income.

Tax gain or loss on the disposition of our common units could be more or less than expected.

If our unitholders sell their common units, they will recognize gain or loss equal to the difference between the amount realized and their tax basis in those common units. Because distributions in excess of a unitholder’s allocable share of our net taxable income decrease the unitholder’s tax basis in their common units, the amount, if any, of such prior excess distributions with respect to their units will, in effect, increase taxable income to the unitholder. Furthermore, a substantial portion of the amount realized, whether or not representing gain, may be taxed as ordinary income due to potential recapture items, including depreciation recapture. In addition, because the amount realized includes a unitholder’s share of our non-recourse liabilities, if a unitholder sells units, the unitholder may incur taxable income in excess of the amount of cash received from the sale.

Tax-exempt entities face unique tax issues from owning our common units that may result in adverse tax consequences to them.

Investment in our common units by tax-exempt entities, such as employee benefit plans and individual retirement accounts (known as IRAs), raises issues unique to them. For example, virtually all of our income allocated to organizations that are exempt from federal income tax, including IRAs and other retirement plans, will be unrelated business taxable income and will be taxable to them. Furthermore, a tax-exempt entity’s gain on sale of common units may be treated, at least in part, as unrelated business taxable income. Tax-exempt entities should consult their tax advisor before investing in our common units.

Non-U.S. unitholders will be subject to United States taxes and withholding with respect to their income and gain from owning our units.

Non-U.S. unitholders are generally taxed and subject to income tax filing requirements by the United States on income effectively connected with a U.S. trade or business. All income allocated to our unitholders and any gain from the sale of our units will generally be considered to be “effectively connected” with a U.S. trade or business. As a result, all distributions to non-U.S. unitholders will be subject to withholding taxes at the highest applicable effective tax rate, and, in the event of a sale of our units by a non-U.S. unitholder, such non-U.S. unitholder will be subject to withholding taxes on all proceeds attributable to the sale of such units.

Furthermore, while non-U.S. unitholders are subject to additional withholding on distributions in excess of cumulative net income, we do not calculate cumulative net income for withholding purposes. Consequently, all of our distributions to non-U.S. unitholders will be subject to such additional withholding.

Non-U.S. unitholders will be required to file U.S. federal tax returns and pay tax on their share of our taxable income. Non-U.S. unitholders will also potentially have tax filings and payment obligations in additional jurisdictions.

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We treat each purchaser of common units as having the same tax benefits without regard to the actual units purchased. The IRS may challenge this treatment, which could adversely affect the value of the common units.

Because we cannot match transferors and transferees of common units and to enable the uniformity of the economic and tax characteristics of common units, we have adopted depreciation and amortization positions that may not conform to all aspects of existing Treasury Regulations. A successful IRS challenge to those positions could adversely affect the amount of tax benefits available to our unitholders. It also could affect the timing of these tax benefits or the amount of gain from the sale of common units and could have a negative impact on the value of our common units or result in audit adjustments to our unitholders’ tax returns.

Our unitholders will likely be subject to state and local taxes and return filing requirements in states where they do not live as a result of investing in our units.

In addition to federal income taxes, our unitholders will likely be subject to other taxes, including state and local taxes, unincorporated business taxes and estate, inheritance or intangible taxes that are imposed by the various jurisdictions in which we do business or own property now or in the future, even if our unitholders do not live in any of those jurisdictions. Our unitholders will likely be required to file state and local income tax returns and pay state and local income taxes in some or all of these various jurisdictions. Further, our unitholders may be subject to penalties for failure to comply with those requirements. We currently conduct business in a substantial number of states, most of which currently impose a personal income tax and many of which impose an income tax on corporations and other entities. As we make acquisitions or expand our business, we may own assets or conduct business in additional states. It is our unitholders’ responsibility to file all U.S. federal, state and local tax returns.

We have adopted certain valuation methodologies that may result in a shift of income, gain, loss and deduction between our general partner and our unitholders. The IRS may challenge this treatment, which could adversely affect the value of the common units.

When we issue additional units or engage in certain other transactions, we must determine the fair market value of our assets and allocate any unrealized gain or loss attributable to our assets to the capital accounts of our unitholders and our general partner. Our methodology may be viewed as understating the value of our assets. In that case, there may be a shift of income, gain, loss and deduction between certain unitholders and the general partner, which may be unfavorable to such unitholders. Moreover, under our valuation methods, subsequent purchasers of common units may have a greater portion of their Internal Revenue Code Section 743(b) adjustment allocated to our tangible assets and a lesser portion allocated to our intangible assets. The IRS may challenge our valuation methods, our allocation of the Section 743(b) adjustment attributable to our tangible and intangible assets, or our allocations of income, gain, loss and deduction between our general partner and certain of our unitholders.

A successful IRS challenge to these methods or allocations could adversely affect the amount of taxable income or loss being allocated to our unitholders. It also could affect the amount of gain from our unitholders’ sale of common units and could have a negative impact on the value of the common units or result in audit adjustments to our unitholders’ tax returns without the benefit of additional deductions.

A unitholder whose common units are the subject of a securities loan (e.g., a loan to a short seller) may be considered as having disposed of those common units. If so, the unitholder would no longer be treated for tax purposes as a partner with respect to those common units during the period of the loan and may recognize gain or loss from the disposition.

A unitholder whose common units are the subject of a securities loan (i) may be considered as having disposed of the loaned common units, (ii) may no longer be treated for tax purposes as a partner with respect to those common units during the period of the loan to the short seller and (iii) may recognize gain or loss from such disposition.

Moreover, during the period of the loan, any of our income, gain, loss or deduction with respect to those common units may not be reportable by the unitholder and any distributions received by the unitholder as to those common units could be fully taxable as ordinary income. Unitholders desiring to assure their status as partners and avoid the risk of gain recognition from a securities loan are urged to consult a tax adviser to discuss whether it is advisable to modify any applicable brokerage account agreements to prohibit their brokers from borrowing their common units.

The tax treatment of publicly traded partnerships or an investment in our units could be subject to potential legislative, judicial or administrative changes and differing interpretations, possibly on a retroactive basis.

The present U.S. federal income tax treatment of publicly traded partnerships, including us, or an investment in our common units may be modified by administrative, legislative or judicial interpretation at any time. From time to time, the President and members of the U.S. Congress propose and consider substantive changes to the existing U.S. federal income tax laws that would affect publicly traded partnerships, including proposals that would eliminate our ability to qualify for partnership tax treatment.

We are unable to predict whether any such changes will ultimately be enacted. Any modification to the U.S. federal income tax laws and interpretations thereof may or may not be applied retroactively and could make it more difficult or impossible to meet

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the exception for certain publicly traded partnerships to be treated as partnerships for U.S. federal income tax purposes or increase the amount of taxes payable by unitholders in publicly traded partnerships.

We generally prorate our items of income, gain, loss and deduction between transferors and transferees of our units each month based upon the ownership of our units on the first day of each month, instead of on the basis of the date a particular unit is transferred. The IRS may challenge this treatment, which could change the allocation of items of income, gain, loss and deduction among our unitholders.

We generally prorate our items of income, gain, loss and deduction between existing unitholders and unitholders who purchase our units based upon the ownership of our units on the first day of each month, instead of on the basis of the date a particular unit is transferred. Similarly, we generally allocate certain deductions for depreciation of capital additions, gain or loss realized on a sale or other disposition of our assets and, in the discretion of our general partner, any other extraordinary item of income, gain, loss or deduction based upon ownership on the allocation date. Treasury Regulations allow a similar monthly simplifying convention, but such regulations do not specifically authorize all aspects of the proration method we have adopted. If the IRS were to challenge our proration method or new Treasury Regulations were issued, we may be required to change the allocation of items of income, gain, loss and deduction among our unitholders.

Unitholders may be subject to limitations on their ability to deduct interest expense we incur.

In general, we are entitled to a deduction for interest paid or accrued on indebtedness properly allocable to our trade or business during our taxable year. However, under the Tax Cuts and Jobs Act, for taxable years beginning after December 31, 2017, our deduction for “business interest” generally became limited to the sum of our business interest income and 30 percent of our “adjusted taxable income.” For the purposes of this limitation, our adjusted taxable income is computed without regard to any business interest expense or business interest income, and in the case of taxable years beginning before January 1, 2022, our adjusted taxable income was also computed without regard to any depreciation or amortization. The Tax Cuts and Jobs Act provided that for taxable years beginning on or after January 1, 2022, adjusted taxable income would need to be computed taking into account any depreciation or amortization for this purpose, but the One Big Beautiful Bill Act, passed on July 4, 2025, reversed this change, and we may again add back depreciation and amortization in computing adjusted taxable income.

If our “business interest” is subject to limitation under these rules, our unitholders will be limited in their ability to deduct their share of any interest expense that has been allocated to them in the current taxable year and may be limited in their ability to deduct such interest expense in a future taxable year. As a result, unitholders may be subject to limitation on their ability to deduct interest expense incurred by us.

If the IRS makes audit adjustments to our income tax returns for tax years beginning after 2017, it (and some states) may collect any resulting taxes (including any applicable penalties and interest) directly from us, in which case our cash available for distribution to our unitholders might be substantially reduced.

If the IRS makes audit adjustments to our income tax returns for tax years beginning after December 31, 2017, it (and some states) may collect any resulting taxes (including any applicable penalties and interest) directly from us. We will generally have certain limited rights to shift any such tax liability to our general partner and our unitholders in accordance with their interests in us during the year under audit, but there can be no assurance that we will be able to do so (or choose to do so) under all circumstances. As a result, our current unitholders may bear some or all of the tax liability resulting from such audit adjustment, even if such unitholders did not own units in us during the tax year under audit. If we are required to make payments of taxes, penalties and interest resulting from audit adjustments, our cash available for distribution to our unitholders might be reduced.

Common Unit Ownership Risks

Our general partner and its affiliates, including MPC, have conflicts of interest with us and limited duties to us and our unitholders, and they may favor their own interests to our detriment and that of our unitholders. Additionally, we have no control over MPC’s business decisions and operations, and MPC is under no obligation to adopt a business strategy that favors us.

MPC owned our general partner and approximately 64 percent of our outstanding common units as of February 20, 2026. Although our general partner has a duty to manage us in a manner that is not adverse to the best interests of our partnership,

conflicts of interest may arise between MPC and its affiliates, including our general partner, on the one hand, and us and our unitholders, on the other hand. In resolving these conflicts, the general partner may favor its own interests and the interests of its affiliates, including MPC, over the interests of our common unitholders, which may occur under our Partnership Agreement without being independently reviewed by the conflicts committee. These conflicts include, among others, the following situations:

• neither our Partnership Agreement nor any other agreement requires MPC to pursue a business strategy that favors us or utilizes our assets, which could involve decisions by MPC to increase or decrease refinery production, shut down or reconfigure a refinery, or pursue and grow particular markets;

• MPC’s directors and officers have a fiduciary duty to make decisions in the best interests of the stockholders of MPC;

• disputes may arise under agreements pursuant to which MPC and its affiliates are our customers;

• MPC may be constrained by the terms of its debt instruments from taking actions, or refraining from taking actions, that may be in our best interests;

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• except in limited circumstances, our general partner has the power and authority to conduct our business without unitholder approval;

• our general partner will determine the amount and timing of asset purchases and sales, borrowings, issuance of additional partnership securities and the creation, reduction or increase of cash reserves, each of which can affect the amount of cash that is distributed to our unitholders;

• our general partner will determine the amount and timing of many of our cash expenditures and whether a cash expenditure is classified as an expansion capital expenditure, which would not reduce operating surplus, or a maintenance capital expenditure, which would reduce our operating surplus. This determination can affect the amount of cash that is distributed to our unitholders, including MPC, and the amount of adjusted operating surplus generated in any given period;

• our general partner will determine which costs incurred by it are reimbursable by us and may cause us to pay it or its affiliates for any services rendered to us;

• our general partner may cause us to borrow funds in order to permit the payment of distributions;

• our Partnership Agreement permits us to classify up to $60 million as operating surplus, even if it is generated from asset sales, non-working capital borrowings or other sources that would otherwise constitute capital surplus. This cash may be used to fund distributions to our unitholders, including MPC;

• our Partnership Agreement does not restrict our general partner from entering into additional contractual arrangements with it or its affiliates on our behalf;

• our general partner intends to limit its liability regarding our contractual and other obligations;

• our general partner may exercise its right to call and purchase all of the common units not owned by it and its affiliates if it and its affiliates own more than 85 percent of the common units;

• our general partner controls the enforcement of obligations owed to us by our general partner and its affiliates, including our transportation and storage services agreements with MPC; and

• our general partner decides whether to retain separate counsel, accountants or others to perform services for us.

Under the terms of our Partnership Agreement, the doctrine of corporate opportunity, or any analogous doctrine, does not apply to our general partner or any of its affiliates, including its executive officers, directors and owners.

Any such person or entity that becomes aware of a potential transaction, agreement, arrangement or other matter that may be an opportunity for us will not have any duty to communicate or offer such opportunity to us. Any such person or entity will not be liable to us or to any limited partner for breach of any fiduciary duty or other duty by reason of the fact that such person or entity pursues or acquires such opportunity for itself, directs such opportunity to another person or entity or does not communicate such opportunity or information to us. This may create actual and potential conflicts of interest between us and affiliates of our general partner and result in less than favorable treatment of us and our unitholders.

Our Partnership Agreement requires that we distribute all of our available cash, which could limit our ability to grow and make acquisitions.

Our Partnership Agreement requires that we distribute all of our available cash to our unitholders. As a result, we may require external financing sources, including commercial bank borrowings and the issuance of debt and equity securities, to fund our acquisitions and expansion capital expenditures. Therefore, to the extent we are unable to finance our growth externally, our cash distribution policy will significantly impair our ability to grow. In addition, because we will distribute all of our available cash, our growth may not be as fast as that of businesses that reinvest their available cash to expand ongoing operations. To the extent we issue additional units in connection with any acquisitions or expansion capital expenditures, the payment of distributions on those additional units may increase the risk that we will be unable to maintain or increase our per unit distribution level. The incurrence of additional commercial borrowings or other debt to finance our growth strategy would result in increased interest expense, which, in turn, may reduce the amount of cash available to distribute to our unitholders.

Our Partnership Agreement replaces our general partner’s fiduciary duties to holders of our common units with contractual standards governing its duties and restricts the remedies available to unitholders for actions taken by our general partner.

Our Partnership Agreement contains provisions that eliminate the fiduciary standards to which our general partner would otherwise be held by state fiduciary duty law and replaces those duties with several different contractual standards. For example, our Partnership Agreement permits our general partner to make a number of decisions in its individual capacity, as opposed to in its capacity as our general partner, free of any duties to us and our unitholders other than the implied contractual covenant of good faith and fair dealing. Our general partner is entitled to consider only the interests and factors that it desires and is relieved of any duty or obligation to give consideration to any interest of, or factors affecting, us, our affiliates or our limited partners.

Our Partnership Agreement contains provisions that restrict the remedies available to unitholders for actions taken by our general partner that might otherwise constitute breaches of fiduciary duty under state fiduciary duty law. For example, our Partnership Agreement:

• provides that whenever our general partner makes a determination or takes, or declines to take, any other action in its capacity as our general partner, our general partner is required to make such determination, or take or decline to take

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such other action, in good faith and will not be subject to any other or different standard imposed by our Partnership Agreement, Delaware law, or any other law, rule or regulation, or at equity;

• provides that our general partner will not have any liability to us or our unitholders for decisions made in its capacity as a general partner so long as it acted in good faith;

• provides that our general partner and its officers and directors will not be liable for monetary damages to us or our limited partners resulting from any act or omission unless there has been a final and non-appealable judgment entered by a court of competent jurisdiction determining that our general partner or its officers and directors, as the case may be, acted in bad faith or engaged in fraud or willful misconduct or, in the case of a criminal matter, acted with knowledge that the conduct was criminal; and

• provides that our general partner will not be in breach of its obligations under our Partnership Agreement or any of its duties to us or our limited partners if a transaction with an affiliate or the resolution of a conflict of interest is approved in accordance with, or otherwise meets the standards set forth in, our Partnership Agreement.

In connection with a transaction with an affiliate or a conflict of interest, our Partnership Agreement provides that any determination by our general partner must be made in good faith, and that our conflicts committee and the board of directors of our general partner are entitled to a presumption that they acted in good faith. In any proceeding brought by or on behalf of any limited partner or the partnership, the person bringing or prosecuting such proceeding will have the burden of overcoming such presumption. By purchasing a common unit, a unitholder is treated as having consented to the provisions in our Partnership Agreement, including the provisions discussed above.

Unitholders have very limited voting rights and, even if they are dissatisfied, they have limited ability to remove our general partner without its consent.

Unlike the holders of common stock in a corporation, unitholders have only limited voting rights on matters affecting our business and, therefore, limited ability to influence management’s decisions regarding our business. Unitholders did not elect our general partner or the board of directors of our general partner and will have no right to elect our general partner or the board of directors of our general partner on an annual or other continuing basis. The board of directors of our general partner is chosen by the members of our general partner, which are wholly owned subsidiaries of MPC. Furthermore, if the unitholders are dissatisfied with the performance of our general partner, they will have little ability to remove our general partner. The vote of the holders of at least 66 2/3 percent of all outstanding common units voting together as a single class is required to remove our general partner. As of February 20, 2026, our general partner and its affiliates owned approximately 64 percent of the outstanding common units (excluding common units held by officers and directors of our general partner and MPC). As a result of these limitations, the price at which our common units will trade could be diminished because of the absence or reduction of a takeover premium in the trading price.

Furthermore, unitholders’ voting rights are further restricted by the Partnership Agreement provision providing that any units held by a person that owns 20 percent or more of any class of units then outstanding, other than our general partner, its affiliates, their transferees, and persons who acquired such units with the prior approval of the board of directors of our general partner, cannot vote on any matter.

Our Partnership Agreement also contains provisions limiting the ability of unitholders to call meetings or to acquire information about our operations, as well as other provisions limiting the unitholders’ ability to influence the manner or direction of management.

If unitholders are not both citizenship-eligible holders and rate-eligible holders, their common units may be subject to redemption.

In order to avoid (1) any material adverse effect on the maximum applicable rates that can be charged to customers by our subsidiaries on assets that are subject to rate regulation by the FERC or analogous regulatory body and (2) any substantial risk of cancellation or forfeiture of any property, including any governmental permit, endorsement or other authorization, in which we have an interest, we have adopted certain requirements regarding those investors who may own our common units. Citizenship eligible holders are individuals or entities whose nationality, citizenship or other related status does not create a substantial risk of cancellation or forfeiture of any property, including any governmental permit, endorsement or authorization, in which we have an interest, and will generally include individuals and entities who are U.S. citizens. Rate-eligible holders are individuals or entities subject to U.S. federal income taxation on the income generated by us or entities not subject to U.S. federal income taxation on the income generated by us, so long as all of the entity’s owners are subject to such taxation. If unitholders are not persons who meet the requirements to be citizenship-eligible holders and rate-eligible holders, they run the risk of having their units redeemed by us at the market price as of the date three days before the date the notice of redemption is mailed. The redemption price will be paid in cash or by delivery of a promissory note, as determined by our general partner. In addition, if unitholders are not persons who meet the requirements to be citizenship eligible holders, they will not be entitled to voting rights.

Cost reimbursements, which will be determined in our general partner’s sole discretion, and fees due our general partner and its affiliates for services provided will be substantial and will reduce our cash available for distribution.

Under our Partnership Agreement, we are required to reimburse our general partner and its affiliates for all costs and expenses that they incur on our behalf for managing and controlling our business and operations. Except to the extent specified under our omnibus agreements or our employee services agreements, our general partner determines the amount of these expenses.

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Under the terms of the omnibus agreements, we will be required to reimburse MPC for the provision of certain general and administrative services to us. Under the terms of our employee services agreements, we have agreed to reimburse MPC or its affiliates for the provision of certain operational and management services to us in support of our facilities. Our general partner and its affiliates also may provide us other services for which we will be charged fees as determined by our general partner. Payments to our general partner and its affiliates are substantial and reduce the amount of cash available for distribution to unitholders.

The control of our general partner may be transferred to a third party without unitholder consent.

There is no restriction in our Partnership Agreement on the ability of MPC to transfer its membership interest in our general partner to a third party. The new members of our general partner would then be in a position to replace the board of directors and officers of our general partner with their own choices and to control the decisions taken by our general partner.

We may issue additional units without unitholder approval, which will dilute limited unitholder interests.

At any time, we may issue an unlimited number of limited partner interests of any type, including limited partner interests that are convertible into our common units, without the approval of our unitholders and our unitholders will have no preemptive or other rights (solely as a result of their status as unitholders) to purchase any such limited partner interests. Further, neither our Partnership Agreement nor our bank revolving credit facility prohibits the issuance of additional preferred units, or other equity securities that may effectively rank senior to our common units as to distributions or liquidations. The issuance by us of additional common units, preferred units or other equity securities of equal or senior rank will have the following effects:

• our unitholders’ proportionate ownership interest in us will decrease;

• it may be more difficult to maintain or increase our distributions to unitholders, and the amount of cash available for distribution on each unit may decrease;

• the ratio of taxable income to distributions may increase;

• the relative voting strength of each previously outstanding unit may be diminished; and

• the market price of our common units may decline.

MPC may sell units in the public or private markets, and such sales could have an adverse impact on the trading price of the common units.

As of February 20, 2026, MPC held 647,415,452 common units. Additionally, we have agreed to provide MPC with certain registration rights. The sale of these units in the public or private markets could have an adverse impact on the price of the common units or on any trading market that may develop.

Affiliates of our general partner, including MPC, may compete with us, and neither our general partner nor its affiliates have any obligation to present business opportunities to us.

MPC and other affiliates of our general partner are not prohibited from owning assets or engaging in businesses that compete directly or indirectly with us. In addition, MPC and other affiliates of our general partner may acquire, construct or dispose of additional midstream assets in the future without any obligation to offer us the opportunity to purchase any of those assets. As a result, competition from MPC and other affiliates of our general partner could materially and adversely impact our results of operations and cash available for distribution to unitholders.

Our general partner has a limited call right that may require unitholders to sell common units at an undesirable time or price.

If at any time our general partner and its affiliates own more than 85 percent of our common units, our general partner will have the right, but not the obligation, which it may assign to any of its affiliates or to us, to acquire all, but not less than all, of the common units held by unaffiliated persons at a price not less than their then current market price. As a result, unitholders may be required to sell their common units at an undesirable time or price and may not receive any return on their investment. Unitholders may also incur a tax liability upon a sale of such units.

A unitholder’s liability may not be limited if a court finds that unitholder action constitutes control of our business.

A general partner of a partnership generally has unlimited liability for the obligations of the partnership, except for those contractual obligations of the partnership that are expressly made non-recourse to the general partner. Our partnership is organized under Delaware law, and we conduct business in a number of other states. The limitations on the liability of holders of limited partner interests for the obligations of a limited partnership have not been clearly established in some jurisdictions. A unitholder could be liable for our obligations as if they were a general partner if a court or government agency were to determine that:

• we were conducting business in a state but had not complied with that particular state’s partnership statute; or

• a unitholder’s right to act with other unitholders to remove or replace the general partner, to approve some amendments to our Partnership Agreement or to take other actions under our Partnership Agreement constitute “control” of our business.

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Unitholders may have to repay distributions that were wrongfully distributed to them.

Under certain circumstances, unitholders may have to repay amounts wrongfully distributed to them. Under Section 17-607 of the Delaware Revised Uniform Limited Partnership Act, we may not make a distribution to unitholders if the distribution would cause our liabilities to exceed the fair value of our assets. Delaware law provides that for a period of three years from the date of the impermissible distribution, limited partners who received the distribution and who knew at the time of the distribution that it violated Delaware law will be liable to the limited partnership for the distribution amount. Transferees of common units are liable for the obligations of the transferor to make contributions to the partnership that are known to the transferee at the time of the transfer and for unknown obligations if the liabilities could be determined from our Partnership Agreement. Liabilities to partners on account of their partnership interest and liabilities that are non-recourse to the partnership are not counted for purposes of determining whether a distribution is permitted.

The NYSE does not require a publicly traded limited partnership like us to comply with certain of its corporate governance requirements.

We list our common units on the NYSE. Because we are a publicly traded limited partnership, the NYSE does not require us to have a majority of independent directors on our general partner’s board of directors or to establish a compensation committee or a nominating and corporate governance committee. Accordingly, unitholders will not have the same protections afforded to certain corporations that are subject to all of the NYSE corporate governance requirements.

The Court of Chancery of the State of Delaware will be, to the extent permitted by law, the sole and exclusive forum for substantially all disputes between us and our limited partners.

Our limited partnership agreement provides that the Court of Chancery of the State of Delaware will be the sole and exclusive forum for any claims, actions or proceedings:

• arising out of or relating in any way to our limited partnership agreement, or the rights or powers of, or restrictions on, our limited partners or the limited partnership;

• brought in a derivative manner on behalf of the limited partnership;

• asserting a claim of breach of a duty owed by any director, officer, or other employee of the limited partnership or the general partner, or owed by the general partner, to the partnership or the limited partners;

• asserting a claim arising pursuant to any provision of the Delaware Revised Uniform Limited Partnership Act; or

• asserting a claim governed by the internal affairs doctrine.

The forum selection provision may restrict a limited partner's ability to bring a claim against us or directors, officers or other employee of ours or our general partner in a forum that it finds favorable, which may discourage limited partners from bringing such claims at all. Alternatively, if a court were to find the forum selection provision contained in our limited partnership agreement to be inapplicable or unenforceable in an action, we may incur additional costs associated with resolving such action in another forum, which could materially adversely affect our business, financial condition and results of operations. However, the forum selection provision does not apply to any claims, actions or proceedings arising under the Securities Act or the Exchange Act.

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

This section of the Annual Report on Form 10-K does not address certain items regarding the year ended December 31, 2023. Discussion and analysis of 2023 and year-to-year comparisons between 2024 and 2023 not included in this Annual Report on Form 10-K can be found in Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations of our Annual Report on Form 10-K for the year ended December 31, 2024.

All statements in this section, other than statements of historical fact, are forward-looking statements that are inherently uncertain. See Disclosures Regarding Forward-Looking Statements and Item 1A. Risk Factors for a discussion of the factors that could cause actual results to differ materially from those projected in these statements. The following information concerning our business, results of operations and financial condition should also be read in conjunction with the information included under Item 1. Business, Item 1A. Risk Factors and Item 8. Financial Statements and Supplementary Data.

MPLX OVERVIEW

We are a diversified, large-cap MLP formed by MPC in 2012 that owns and operates midstream energy infrastructure and logistics assets, and provides fuels distribution services. Our assets include a network of crude oil and refined product pipelines; an inland marine business; light-product, asphalt, heavy oil and marine terminals; storage caverns; refinery tanks, docks, loading racks and associated piping; crude oil and natural gas gathering systems and pipelines; as well as natural gas and NGL processing and fractionation facilities. 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 assets are positioned throughout the United States. The Crude Oil and Products Logistics segment primarily engages in the gathering, transportation, storage and distribution of crude oil, refined products, other hydrocarbon-based products and renewables. The Crude Oil and Products Logistics segment also includes the operation of our refining logistics, fuels distribution and inland marine businesses, terminals, rail facilities and storage caverns. The Natural Gas and NGL Services segment provides gathering, treating, processing and transportation of natural gas as well as the transportation, fractionation, storage and marketing of NGLs.

SIGNIFICANT FINANCIAL AND OTHER HIGHLIGHTS

Significant financial and other highlights for the years ended December 31, 2025, 2024 and 2023 are shown in the chart below. Refer to the Results of Operations, the Liquidity and Capital Resources, and Non-GAAP Financial Information 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

• Generated $5.9 billion of net cash provided by operating activities, $5.8 billion of distributable cash flow attributable to MPLX, and $1.0 billion of adjusted free cash flow (“Adjusted FCF”).

• Paid $4.0 billion in distributions during the year ended December 31, 2025, which includes a 12.5 percent increase in our quarterly distribution effective for the third quarter of 2025, in line with our commitment to return capital to unitholders.

• Repurchased $400 million of common units held by the public during the year ended December 31, 2025.

• Expanded our crude oil value chain in March 2025 by acquiring gathering businesses from Whiptail Midstream, LLC.

• In June 2025, acquired an additional five percent interest in the joint venture that owns and operates the Matterhorn Express Pipeline.

• 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”).

• Completed the acquisition of Northwind Midstream in August 2025 for $2.4 billion in cash (the “Northwind Midstream Acquisition”).

• Sold our Rockies gathering and processing operations to a subsidiary of Harvest Midstream in November 2025 for $980 million in cash consideration.

Current Economic Environment

We continue to see production increases across our key operating regions in the Marcellus and Utica, where 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, we believe 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 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

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activities as they have important limitations as analytical tools because they exclude some but not all items that affect net income and net cash provided by operating activities or any other measure of financial performance or liquidity presented in accordance with GAAP. These non-GAAP financial measures should not be considered in isolation or as substitutes for analysis of our results as reported under GAAP. Additionally, because non-GAAP financial measures may be defined differently by other companies in our industry, our definitions may not be comparable to similarly titled measures of other companies, thereby diminishing their utility. For a reconciliation of Adjusted EBITDA and DCF to their most directly comparable measures calculated and presented in accordance with GAAP, see Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations – 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 Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations – Liquidity and Capital Resources.

COMPARABILITY OF OUR FINANCIAL RESULTS

During the normal course of business, we amend or modify our contractual agreements with customers. These amendments or modifications require the agreements to be reassessed under GAAP, which can impact the classification of revenues or costs associated with the agreement. These reassessments may impact the comparability of our financial results.

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RESULTS OF OPERATIONS

The following tables and discussion summarize our results of operations for the years ended 2025, 2024 and 2023, 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.

(In millions)

$ Change

$ Change

Revenues and other income:

Service revenue

Rental income

Product related revenue

Sales-type lease revenue

Income from equity method investments

Gain on equity method investments

Other income

Total revenues and other income

Costs and expenses:

Cost of revenues (excludes items below)

Purchased product costs

Rental cost of sales

Purchases - related parties

Depreciation and amortization

General and administrative expenses

Other taxes

Total costs and expenses

Income from operations

Net interest and other financial costs

Income before income taxes

Provision for income taxes

Net income

Less: Net income attributable to noncontrolling interests

Net income attributable to MPLX LP

Adjusted EBITDA attributable to MPLX LP (1)

DCF attributable to MPLX (1)

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

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(In millions)

Reconciliation of Adjusted EBITDA attributable to MPLX LP and DCF attributable to LP unitholders from Net income:

Net income

Provision for income taxes

Net interest and other financial costs

Income from operations

Depreciation and amortization

Income from equity method investments

Distributions/adjustments related to equity method investments

Gain on equity method investments

Gain on sale of assets

Transaction-related costs (1)

Garyville incident response costs (2)

Other (3)

Adjusted EBITDA

Adjusted EBITDA attributable to noncontrolling interests

Adjusted EBITDA attributable to MPLX LP

Deferred revenue impacts

Sales-type lease payments, net of income

Adjusted net interest and other financial costs (4)

Maintenance capital expenditures, net of reimbursements

Equity method investment maintenance capital expenditures paid out

Other

DCF attributable to MPLX LP

Preferred unit distributions

DCF attributable to LP unitholders

(1) Transaction-related costs include costs associated with the Northwind Midstream Acquisition, the BANGL Acquisition and the divestiture of the Rockies gathering and processing operations discussed in Item 8. Financial Statements and Supplementary Data – Note 4.

(2) In August 2023, a naphtha release and resulting fire occurred at our Garyville Tank Farm resulting in the loss of four storage tanks with a combined shell capacity of 894 thousand barrels (“Garyville Incident”). We incurred $16 million of incident response costs, net of insurance recoveries, during the year ended December 31, 2023.

(3) Includes unrealized derivative gains and/or losses, equity-based compensation and other miscellaneous items.

(4) Represents Net interest and other financial costs excluding gains and/or losses on extinguishment of debt and amortization of deferred financing costs.

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(In millions)

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

Changes in working capital items

All other, net

Loss on extinguishment of debt

Adjusted net interest and other financial costs (1)

Other adjustments to equity method investment distributions

Transaction-related costs (2)

Garyville Incident response costs (3)

Other

Adjusted EBITDA

Adjusted EBITDA attributable to noncontrolling interests

Adjusted EBITDA attributable to MPLX LP

Deferred revenue impacts

Sales-type lease payments, net of income

Adjusted net interest and other financial costs (1)

Maintenance capital expenditures, net of reimbursements

Equity method investment maintenance capital expenditures paid out

Other

DCF attributable to MPLX LP

Preferred unit distributions

DCF attributable to LP unitholders

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

(2)    Transaction-related costs include costs associated with the Northwind Midstream Acquisition, the BANGL Acquisition and the divestiture of the Rockies gathering and processing operations discussed in Item 8. Financial Statements and Supplementary Data – Note 4.

(3)    We incurred $16 million of Garyville Incident response costs, net of insurance recoveries, during the year ended December 31, 2023.

2025 Compared to 2024

Net income attributable to MPLX increased $595 million in 2025 compared to 2024 primarily due to a $484 million gain from the BANGL Acquisition, annual fee escalations, higher throughputs and benefits from recent acquisitions.

Total revenues and other income increased by $1.1 billion in 2025 compared to 2024 primarily due to:

• Increased Service revenue of $342 million primarily due $132 million of crude oil and products logistics tariff and other fee increases, $96 million from recent acquisitions, $93 million of higher pipeline throughput and a $37 million benefit from a FERC tariff ruling issued in November 2025.

• Increased Rental income of $45 million primarily due to changes in the presentation of lease income between sales-type lease revenue, service revenue and rental income as a result of lease contract modifications, and annual fee escalations related to our refining logistics assets.

• Increased Product related revenue of $195 million due to higher NGL sales volumes in the Southwest and Marcellus of $347 million and a $27 million non-recurring benefit associated with a customer agreement, partially offset by lower revenue in the Rockies of $101 million, including the impact of the Rockies divestiture, and lower NGL prices in the Southwest, Marcellus and Southern Appalachia of $76 million.

• Decreased Income from equity method investments of $105 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.

• Increased Other income of $136 million primarily due to a $159 million gain from the Rockies divestiture, partially offset by lower insurance proceeds of $41 million.

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Total costs and expenses increased by $410 million in 2025 compared to 2024 primarily due to:

• Increased Cost of revenues of $1 million primarily due to lower NGL purchases in the Rockies of $89 million, which are now reflected in Purchased product costs due to changes in certain customer contracts, partially offset by higher net operating costs and repairs and maintenance costs of $60 million and the consolidation of recent acquisitions of $34 million.

• Increased Purchased product costs of $254 million primarily due to higher NGL volumes in the Southwest of $276 million and higher NGL volumes in the Rockies of $47 million, which were previously recorded in Cost of revenues due to changes in certain customer contracts, partially offset by lower NGL prices in the Southwest of $52 million.

• Increased Purchases-related parties of $66 million primarily due to increased employee costs from MPC.

• Increased Depreciation and amortization of $68 million primarily due to incremental depreciation associated with recent acquisitions as well as other assets placed in service in 2025.

SEGMENT RESULTS

We classify our business in the following 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.

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 reportable segments for the years ended December 31, 2025, 2024 and 2023.

Crude Oil and Products Logistics Segment

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

Segment revenues and other income

Segment Adjusted EBITDA

(In millions)

$ Change

$ Change

Total segment revenues and other income

Segment Adjusted EBITDA

Capital expenditures

Investments in unconsolidated affiliates (1)

(1)    The year ended December 31, 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 (collectively referred to as the “Bakken Pipeline system”), to fund our share of debt repayments by the joint venture.

2025 Compared to 2024

Total segment revenues and other income increased $236 million in 2025 compared to 2024. The increase was primarily driven by $132 million of tariff and other fee increases, $93 million of increased pipeline throughput, a $37 million benefit from a FERC tariff ruling issued in November 2025, $21 million from the March 2025 Whiptail Midstream, LLC acquisition and $14 million of additional marine equipment in operation, partially offset by lower insurance proceeds of $41 million. Income from equity method investments decreased $26 million in 2025 compared to 2024, primarily driven by lower throughput on certain equity method

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investment pipeline systems. See Supplemental Information on Equity Method Investments for additional information regarding the results of our equity method investments.

Segment Adjusted EBITDA increased $172 million in 2025 compared to 2024. The increase was primarily driven by $132 million of tariff and other fee increases, $93 million of increased pipeline throughput, a $37 million benefit from a FERC tariff ruling issued in November 2025, $17 million from the March 2025 Whiptail Midstream, LLC acquisition and $14 million of additional marine equipment in operation. These increases were partially offset by lower insurance proceeds of $41 million, higher project related spending of $41 million, higher operating costs of $37 million, driven primarily by higher employee costs from MPC, and increased energy costs as a result of higher throughputs, as well as lower distributions and adjustments from equity method investments of $29 million.

Crude Oil and Products Logistics Operating Data

Crude Oil and Products Logistics

Crude oil transported for (mbpd):

MPC

Third parties

Total

% MPC

Refined products transported for (mbpd):

MPC

Third parties

Total

% MPC

Average tariff rates ($ per Bbl) (1) :

Crude oil pipelines

Refined product pipelines

Total pipelines

Terminal throughput (mbpd)

Marine Assets (number in operation)

Barges

Towboats

(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.

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Natural Gas and NGL Services Segment

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

Segment revenues and other income (1)

Segment Adjusted EBITDA

(In millions)

$ Change

$ Change

Total segment revenues and other income (1)

Segment Adjusted EBITDA

Capital expenditures

Investments in unconsolidated affiliates

(1) The year ended December 31, 2024 includes a $151 million gain related to the dilution of ownership interest in connection with the Whistler Joint Venture Transaction. See Item 8. Financial Statements and Supplementary Data – Note 4 for additional information.

2025 Compared to 2024

Total segment revenues and other income increased $829 million in 2025 compared to 2024. The increase was primarily due to the recognition of a $484 million gain from the BANGL Acquisition, $347 million of higher NGL sales volumes in the Southwest and Marcellus, a $159 million gain from the Rockies divestiture, $71 million from recent acquisitions and a $34 million non-recurring benefit associated with a customer agreement. These increases were partially offset by lower income from equity method investments of $79 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, $76 million of lower NGL prices in the Southwest, Marcellus and Southern Appalachia and $57 million of lower throughput and fee rates in the Rockies and Bakken.

Additional impacts from equity method investments included increased throughput and fee rates in certain processing and pipeline joint ventures and a $25 million gain in 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.

Segment Adjusted EBITDA increased $81 million in 2025 compared to 2024. The increase is primarily due to $80 million in contributions from recent acquisitions, $63 million of higher distributions and adjustments from equity method investments, $40 million of higher throughput fee rates, $40 million of higher NGL sales volumes in the Southwest and Marcellus and a $37 million non-recurring benefit associated with a customer agreement. These increases were partially offset by higher operating costs of $55 million, lower volumes in the Rockies and Bakken of $45 million, the impact of the divestiture of non-core gathering and processing assets of $31 million, lower NGL pricing of $26 million and higher project related spending of $18 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)

Natural Gas and NGL Services

Gathering Throughput (MMcf/d)

Marcellus Operations

Utica Operations

Southwest Operations

Bakken Operations

Rockies Operations

Total gathering throughput

Natural Gas Processed (MMcf/d)

Marcellus Operations

Utica Operations

Southwest Operations (3)

Southern Appalachia Operations

Bakken Operations

Rockies Operations

Total natural gas processed

C2 + NGLs Fractionated (mbpd)

Marcellus Operations (4)

Utica Operations (4)

Other (5)

Total C2 + NGLs fractionated (6)

NGL Pipeline Throughput (mbpd)

Marcellus Operations

Utica Operations

Southwest Operations

Other (5)

Total NGL pipeline throughput

(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)    The amounts presented above exclude Northwind Midstream treated volumes during the year ended December 31, 2025.

(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)    Other includes Southern Appalachia, Bakken and Rockies Operations.

(6)     Purity ethane makes up approximately 267 mbpd, 265 mbpd and 233 mbpd of MPLX LP consolidated total fractionated products for the years ended December 31, 2025, 2024 and 2023, respectively. Purity ethane makes up approximately 288 mbpd, 282 mbpd and 240 mbpd of MPLX operated total fractionated products for the years ended December 31, 2025, 2024 and 2023, respectively.

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Pricing Information

Natural Gas NYMEX HH ($/MMBtu)

C2 + NGL Pricing/gallon (1)

(1)     For 2025 and 2024, 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. For 2023, C2 + NGL pricing based on Mont Belvieu prices assuming an NGL barrel of approximately 35 percent ethane, 35 percent propane, six percent Iso-Butane, 12 percent normal butane and 12 percent natural gasoline. The changes in mix from 2023 to 2024 resulted in an approximate $0.13 increase in the calculated C2 + NGL price per gallon.

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SUPPLEMENTAL INFORMATION ON EQUITY METHOD INVESTMENTS

The following table presents MPLX’s income from equity method investments for the years ended December 31, 2025, 2024 and 2023:

(In millions)

Income from equity method investments:

Crude Oil and Products Logistics

Illinois Extension Pipeline Company, L.L.C.

LOOP LLC

MarEn Bakken Company LLC

Other

Total Crude Oil and Products Logistics

Natural Gas and NGL Services

MarkWest EMG Jefferson Dry Gas Gathering Company, L.L.C.

MarkWest Utica EMG, L.L.C.

Ohio Gathering Company L.L.C.

Sherwood Midstream LLC

WPC Parent, LLC (1)

Other (2)

Total Natural Gas and NGL Services

Total

(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 year ended December 31, 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 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 Adjusted EBITDA for the years ended December 31, 2025, 2024 and 2023:

(In millions)

Distributions/adjustments related to equity method investments:

Crude Oil and Products Logistics

Illinois Extension Pipeline Company, L.L.C.

LOOP LLC

MarEn Bakken Company LLC

Other

Total Crude Oil and Products Logistics

Natural Gas and NGL Services

MarkWest EMG Jefferson Dry Gas Gathering Company, L.L.C.

MarkWest Utica EMG, L.L.C.

Ohio Gathering Company L.L.C.

Sherwood Midstream LLC

WPC Parent, LLC (1)

Other

Total Natural Gas and NGL Services

Total

(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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LIQUIDITY AND CAPITAL RESOURCES

Cash Flows

Our cash and cash equivalents were $2,137 million and $1,519 million at December 31, 2025 and December 31, 2024, respectively. 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 for the past three years were as follows:

(In millions)

Net cash provided by/(used in):

Operating activities

Investing activities

Financing activities

Total

Cash Flows Provided by Operating Activities - Net cash provided by operating activities decreased $37 million in 2025 compared to 2024 primarily due to a $182 million increase in working capital requirements, partially offset by improved results of operations and higher cash distributions from equity method investments.

Cash Flows Used in Investing Activities - Net cash used in investing activities increased $2,861 million in 2025 compared to 2024 primarily due to the acquisition of Northwind Midstream for $2,413 million, higher capital spending and the purchase of the remaining 55 percent interest in BANGL for $703 million. The year ended December 31, 2025 also reflects the use of $235 million for the acquisition of Whiptail Midstream, LLC and the purchase of an additional five percent ownership interest in the joint venture that owns and operates the Matterhorn Express pipeline for $151 million. These increases were partially offset by $971 million received from the sale of our Rockies operations.

Cash Flows Used in Financing Activities - Net cash used in financing activities decreased $3,045 million in 2025 compared to 2024. The decrease was primarily driven by increased net debt borrowings of $3,598 million, partially offset by higher distributions paid to unitholders of $421 million as a result of the 12.5 percent increase in our quarterly distribution effective for the third quarter of 2025 and higher unit repurchases of $74 million.

Adjusted Free Cash Flow - For the year ended December 31, 2025, we generated Adjusted FCF of $1.0 billion. This provided us the flexibility to return capital to our unitholders by increasing our quarterly distribution by 12.5 percent in the third quarter of 2025. The table below provides a reconciliation of Adjusted FCF and Adjusted FCF after distributions from net cash provided by operating activities for the years ended December 31, 2025, 2024 and 2023.

(In millions)

Net cash provided by operating activities (1)

Adjustments to reconcile net cash provided by operating activities to adjusted free cash flow

Net cash used in investing activities (2)

Contributions from MPC

Distributions to noncontrolling interests

Adjusted FCF

Distributions paid to common and preferred unitholders

Adjusted FCF after distributions

(1)    The years ended December 31, 2025 , 2024 and 2023 include working capital draws of $65 million, $241 million and $169 million, respectively .

(2)    The year ended December 31, 2025 includes $2.4 billion for the Northwind Midstream Acquisition, $703 million for the BANGL Acquisition, $235 million for the acquisition of Whiptail Midstream, LLC, $151 million for the purchase of an additional five percent ownership interest in the joint venture that owns and operates the Matterhorn Express pipeline, a $49 million capital contribution to WPC Parent, LLC to redeem Enbridge’s special membership interest in the Rio Bravo Pipeline project, and $971 million received from the sale of our Rockies gathering and processing operations.

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Debt and Liquidity Overview

Senior Notes

The following table summarizes debt issuances during the year ended December 31, 2025, all of which were issued in underwritten public offerings:

Issue Date

Aggregate Principal Amount

(in millions)

Note

Coupon (percent)

Price to Public

(percent of par)

Interest Payment Dates

Maturity Date

March 10, 2025

April 1 and October 1

April 1, 2035

March 10, 2025

April 1 and October 1

April 1, 2055

August 11, 2025

February 15 and August 15

February 15, 2031

August 11, 2025

January 15 and July 15

January 15, 2033

August 11, 2025

March 15 and September 15

September 15, 2035

August 11, 2025

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. The remaining net proceeds from this offering were used 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 (as defined below). The remainder of the net proceeds from this offering were used for general partnership purposes.

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”). See Note 4 for additional information on the BANGL Acquisition.

On May 20, 2024, MPLX issued $1.65 billion aggregate principal amount of the 5.50 percent senior notes due June 2034 (the “2034 Senior Notes”) in an underwritten public offering. The 2034 Senior Notes were offered at a price to the public of 98.778 percent of par, with interest payable semi-annually in arrears, commencing on December 1, 2024. On December 1, 2024, MPLX used $1,150 million of the net proceeds from the issuance of the 2034 Senior Notes to repay all of (i) MPLX’s outstanding $1,149 million aggregate principal amount of 4.875 percent senior notes due December 2024 and (ii) MarkWest’s outstanding $1 million aggregate principal amount of 4.875 percent senior notes due December 2024. On February 18, 2025, MPLX used the remaining net proceeds from the issuance of the 2034 Senior Notes to repay all of MPLX’s outstanding $500 million aggregate principal amount of 4.000 percent senior notes due February 2025.

The total issuances of $6.5 billion and total redemptions of $1.7 billion of senior notes during 2025 as discussed above resulted in an aggregate principal amount of senior notes outstanding as of December 31, 2025 of $26 billion, an increase of $4.8 billion compared to December 31, 2024.

On February 12, 2026, MPLX issued $1.0 billion aggregate principal amount of 5.30 percent senior notes due 2036 (the “2036 Senior Notes”) and $500 million aggregate principal amount of 6.10 percent senior notes due 2056 (the “2056 Senior Notes”) in an underwritten public offering. The 2036 Senior Notes were offered at a price to the public of 99.678 percent of par, with interest payable semi-annually in arrears, commencing on October 1, 2026. The 2056 Senior Notes were offered at a price to the public of 98.453 percent of par, with interest payable semi-annually in arrears, commencing on October 1, 2026. We intend to use the net proceeds from the 2036 Senior Notes and 2056 Senior Notes to repay MPLX’s outstanding $1,500 million aggregate principal amount of 1.750 percent senior notes due March 2026 at maturity. Pending final use, we may invest the proceeds in short-term marketable securities or other investments.

Credit Agreement

MPLX’s credit agreement (the “MPLX Credit Agreement”) matures in July 2027 and, among other things, provides for a $2 billion unsecured revolving credit facility and letter of credit issuing capacity under the facility of up to $150 million. Letter of credit issuing capacity is included in, not in addition to, the $2 billion borrowing capacity. Borrowings under the MPLX Credit Agreement bear interest, at MPLX’s election, at either the Adjusted Term SOFR or the Alternate Base Rate, both as defined in the MPLX Credit Agreement, plus an applicable margin.

The borrowing capacity under the MPLX Credit Agreement may be increased by up to an additional $1 billion, subject to certain conditions, including the consent of lenders whose commitments would increase. In addition, the maturity date may be extended for up to two additional one-year periods, subject to, among other conditions, the approval of lenders holding the majority of the commitments then outstanding, provided that the commitments of any non-consenting lenders will terminate on the then-effective maturity date. We are charged various fees and expenses in connection with the agreement, including administrative agent fees, commitment fees on the unused portion of the bank revolving credit facility and fees with respect to issued and outstanding letters of credit. The applicable margins to the benchmark interest rates and certain fees fluctuate based on the credit ratings in effect from time to time on MPLX’s long-term debt.

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The MPLX Credit Agreement contains certain representations and warranties, affirmative and negative covenants and events of default that we consider usual and customary for an agreement of this type, including a financial covenant that requires us to maintain a ratio of Consolidated Total Debt as of the end of each fiscal quarter to Consolidated EBITDA (both as defined in the MPLX Credit Agreement) for the prior four fiscal quarters of no greater than 5.0 to 1.0 (or 5.5 to 1.0 for up to two fiscal quarters following certain acquisitions). Consolidated EBITDA is subject to adjustments, including for certain acquisitions completed and capital projects undertaken during the relevant period. Other covenants restrict us and/or certain of our subsidiaries from incurring debt, creating liens on our assets and entering into transactions with affiliates. As of December 31, 2025, we were in compliance with the covenants contained in the MPLX Credit Agreement.

Activity on the MPLX Credit Agreement during the year ended December 31, 2025 is summarized in the table below.

(in millions, except %)

Borrowings

Weighted average interest rate of borrowings

Repayments

Outstanding balance at end of period (1)

(1)    There was less than $1 million in letters of credit outstanding on the MPLX Credit Agreement.

MPC Loan Agreement

MPLX is party to a loan agreement with MPC (the “MPC Loan Agreement”). 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 Item 8. Financial Statements and Supplementary Data – Note 17.

Activity on the MPC Loan Agreement during the year ended December 31, 2025 is summarized in the table below.

(In millions, except %)

Borrowings

Weighted average interest rate of borrowings

Repayments

Outstanding balance at end of period

For further discussion, see Item 8. Financial Statements and Supplementary Data – Note 6 and Note 17.

Our intention is to maintain an investment grade credit profile. As of February 1, 2026, 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 the MPLX Credit Agreement, and may limit our ability to obtain future financing, including refinancing existing indebtedness.

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Our liquidity totaled $5.6 billion at December 31, 2025, consisting of:

December 31, 2025

(In millions)

Total Capacity

Outstanding Borrowings

Available

Capacity

MPLX Credit Agreement

MPC Loan Agreement

Total

Cash and cash equivalents

Total liquidity

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 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.

Equity and Preferred Units Overview

Preferred Units

On May 13, 2016, MPLX completed the private placement of approximately 30.8 million Series A preferred units for a cash purchase price of $32.50 per unit. The aggregate net proceeds of approximately $984 million from the sale of the preferred units were used for capital expenditures, repayment of debt and general business purposes.

The following conversions were executed in accordance with the conversion provisions outlined in our Partnership Agreement. During the years ended December 31, 2024 and 2023, certain Series A preferred unitholders exercised their rights to convert their Series A preferred units into 21 million common units and 2 million common units, respectively. On February 11, 2025, MPLX exercised its right to convert the remaining 6 million outstanding Series A preferred units into common units. As a result, there were no Series A preferred units outstanding at December 31, 2025.

Prior to conversion, the holders of the Series A preferred units received quarterly distributions equal to the greater of $0.528125 per unit or the amount of distributions they would have received on an as converted basis. Distributions paid to Series A preferred unitholders during the years ended December 31, 2025, 2024 and 2023 were $6 million, $44 million and $94 million, respectively.

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:

(In millions, except per unit data)

Units repurchased

Cash paid for common units repurchased (1)

Average cost per unit (1)

(1) Cash paid for common units repurchased and average cost per unit includes commissions paid to brokers during the period.

As of December 31, 2025, we had $1,120 million remaining under the unit repurchase authorizations.

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Distributions

On January 29, 2026, we announced that the board of directors of our general partner had declared a quarterly cash distribution of $1.0765 per common unit for the fourth quarter of 2025, which was paid on February 17, 2026 to common unitholders of record on February 9, 2026. This represents a 12.5 percent increase over the fourth quarter of 2024 distribution. Although our Partnership Agreement requires that we distribute all of our available cash each quarter, we do not otherwise have a legal obligation to distribute any particular amount per common unit.

The allocation of total quarterly cash distributions to common and preferred unitholders is as follows for the years ended December 31, 2025, 2024 and 2023. Our 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. See additional discussion in Item 8. Financial Statements and Supplementary Data – Note 8.

(In millions, except per unit data)

Distribution declared:

Limited partner common units - public

Limited partner common units - MPC

Total distributions declared to limited partner common units

Series A preferred units

Series B preferred units

Total distribution declared

Cash distributions declared per limited partner common unit:

Quarter ended March 31,

Quarter ended June 30,

Quarter ended September 30,

Quarter ended December 31,

Year ended December 31,

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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, 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.

Our capital expenditures for the past three years are shown in the table below:

(In millions)

Capital expenditures:

Growth capital expenditures

Growth capital reimbursements

Investments in unconsolidated affiliates (1)

Return of capital (2)

Capitalized interest

Total growth capital expenditures (3)

Maintenance capital expenditures

Maintenance capital reimbursements

Capitalized interest

Total maintenance capital expenditures

Total growth and maintenance capital expenditures

Investments in unconsolidated affiliates (1)

Return of capital (2)

Growth and maintenance capital reimbursements (4)

(Increase)/decrease in capital accruals

Capitalized interest

Other

Additions to property, plant and equipment

(1)    Investments in unconsolidated affiliates and additions to property, plant and equipment, net are shown as separate lines within investing activities in the Consolidated Statements of Cash Flows. Investments in unconsolidated affiliates for the years ended December 31, 2025 and December 31, 2024 exclude payments associated with purchases of equity interests in unconsolidated affiliates totaling $213 million and $228 million, respectively.

(2)    Return of capital for the year ended December 31, 2025 excludes $42 million in special distributions received in exchange for the contribution of assets to a joint venture. Return of capital for the year ended December 31, 2024 excludes a $134 million cash distribution in connection with the Whistler Joint Venture Transaction.

(3)    Total growth capital expenditures exclude $3,316 million, $622 million and $246 million of acquisitions, net of cash acquired, in 2025, 2024 and 2023, respectively, and a $134 million cash distribution received in 2024 in connection with the Whistler Joint Venture Transaction. Total growth capital expenditures also exclude purchases of additional equity interests in unconsolidated affiliates of $213 million and $228 million for the years ended December 31, 2025 and December 31, 2024, respectively.

(4)     Growth capital reimbursements are generally included in changes in deferred revenue within the operating activities section of the Consolidated Statements of Cash Flows. Maintenance capital reimbursements are included in the Contributions from MPC line within financing activities section of the Consolidated Statements of Cash Flows.

For 2026, we announced a capital outlook of $2.7 billion, net of reimbursements, and excluding potential acquisitions, if any, which includes growth capital of $2.4 billion and maintenance capital of $300 million. Our growth capital plans are focused on expanding our Permian to Gulf Coast integrated value chain, progressing long-haul pipeline growth projects to support producer activity, and investing in new gas processing plants in the Marcellus and Permian. The remainder of our capital plan targets the debottlenecking of existing assets to meet customer demand. We continuously evaluate our capital plan and make changes as conditions warrant.

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

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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.

(In millions, except ownership percentages)

MPLX Ownership

BANGL, LLC (1)

MXP Parent, LLC (2)

WPC Parent, LLC (3)

All other

Total

(1)    The year ended December 31, 2025 reflects 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. In certain cases, MPLX’s interest in the joint venture, unless otherwise noted, is non-recourse to MPLX in excess of the value of MPLX’s investment in the joint venture. At December 31, 2025, debt held by our unconsolidated joint ventures based on our equity ownership percentage was $1.8 billion.

Cash Commitments

Our material cash requirements include the following contractual obligations and other cash commitments as of December 31, 2025.

Our contractual obligations primarily consist of outstanding borrowings on debt, commitment and administrative fees and interest. Additional information for third-party debt is included in Item 8. Financial Statements and Supplementary Data – Note 17. See Item 8. Financial Statements and Supplementary Data – Note 6 for additional information for the related party loan. Our cash commitment at December 31, 2025 was $43.4 billion, with $2.7 billion payable within 12 months. We intend to repay the short-term maturities with existing cash on hand, short-term borrowings under our revolving credit agreements or with the proceeds of new long-term debt, depending on, among other things, market conditions.

Our contractual commitment for co-location services agreements was $4.1 billion at December 31, 2025. These agreements obligate us to pay MPC for operational and other services provided to the subsidiaries of MPLX Operations LLC. The co-location services agreements have remaining terms up to 43 years.

Finance and operating leases relate primarily to facilities and equipment under lease, including ground leases, building space, office and field equipment, storage facilities and transportation equipment. See Item 8. Financial Statements and Supplementary Data – Note 21 for further discussion about our lease obligations. Our cash commitment at December 31, 2025 was $938 million.

We execute various third-party transportation, terminalling, and gathering and processing agreements that obligate us to minimum volume, throughput or payment commitments over the remaining terms, which range from less than one year to seven years. We expect to pass any minimum payment commitments through to producer customers. These agreements may include escalation clauses based on various inflationary indices; however, those potential increases have not been incorporated in minimum fees due under these agreements presented below. See Item 8. Financial Statements and Supplementary Data – Note 22 for further discussion. Our cash commitment for these agreements at December 31, 2025 was $509 million.

At December 31, 2025, our contractual commitment under contracts to acquire property, plant and equipment was $311 million.

Our other cash commitments consist of expense projects, right of way and easement obligations, natural gas purchase obligations and ARO commitments. These other cash commitments at December 31, 2025 totaled $358 million.

In addition, we have omnibus agreements and employee services agreements with MPC. One of the omnibus agreements with MPC addresses our payment of a fixed annual fee to MPC for the provision of executive management services by certain executive officers of our general partner and our reimbursement to MPC for the provision of certain general and administrative services to us.

We also pay MPC additional amounts based on the costs actually incurred by MPC in providing other services, except for the portion of the amount attributable to engineering services, which is based on the amounts actually incurred by MPC and its affiliates plus an incremental surcharge. In addition, we are obligated to reimburse MPC for most out-of-pocket costs and expenses incurred by MPC on our behalf.

MPLX has various employee agreements with MPC under which MPLX reimburses MPC for employee benefit expenses, along with the provision of operational and management services in support of both our Crude Oil and Products Logistics and Natural Gas and NGL Services segments’ operations.

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We incurred $2.1 billion of costs under various agreements with MPC, including the omnibus, co-location and employee service agreements for 2025.

Effects of Inflation

Inflation did not have a material impact on our results of operations for the years ended December 31, 2025, 2024 or 2023. We have observed higher costs for labor and materials used in our business during the year ended December 31, 2025. Many of our agreements provide for inflation-based adjustments, including the Producer Price Index-FG, Consumer Price Index or the FERC index. To the extent permitted by competition, regulation and our existing agreements, we have and expect to continue to pass along a portion of increased costs to our customers in the form of higher fees.

TRANSACTIONS WITH RELATED PARTIES

As of December 31, 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. For further discussion of agreements and activity with MPC and related parties see Item 1. Business and Item 8. Financial Statements and Supplementary Data – Note 6.

Excluding significant non-cash items, MPC accounted for 48 percent, 49 percent and 50 percent of our total revenues and other income for the years ended December 31, 2025, 2024 and 2023, respectively. Of our total costs and expenses, MPC accounted for 26 percent, 27 percent and 27 percent for the years ended December 31, 2025, 2024 and 2023, respectively.

ENVIRONMENTAL MATTERS AND COMPLIANCE COSTS

We are subject to extensive federal, state and local environmental laws and regulations. These laws, which change frequently, regulate the discharge of materials into the environment or otherwise relate to protection of the environment. Compliance with these laws and regulations may require us to remediate environmental damage from any discharge of hazardous, petroleum or chemical substances from our facilities or require us to install additional pollution control equipment on our equipment and facilities. Our failure to comply with these or any other environmental or safety-related regulations could result in the assessment of administrative, civil or criminal penalties, the imposition of investigatory and remedial liabilities, and the issuance of injunctions that may subject us to additional operational constraints.

Future expenditures may be required to comply with the CAA and other federal, state and local requirements for our various facilities. The impact of these legislative and regulatory developments, if enacted or adopted, could result in increased compliance costs and additional operating restrictions on our business, each of which could have an adverse impact on our financial position, results of operations and liquidity. We expect that certain of these costs will be subject to indemnification by MPC.

Legislation and regulations pertaining to climate change and GHG emissions have the potential to materially adversely impact our business, financial condition, results of operations and cash flows, including costs of compliance and permitting delays. The extent and magnitude of these adverse impacts cannot be reliably or accurately estimated at this time because specific regulatory and legislative requirements have not been finalized and uncertainty exists with respect to the measures being considered, the costs and the time frames for compliance, and our ability to pass compliance costs on to our customers.

We have incurred and may continue to incur substantial capital, operating and maintenance, and remediation expenditures as a result of these environmental laws and regulations. If these expenditures, as with all costs, are not ultimately reflected in the fees and tariff rates we receive for our 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. Our environmental expenditures for each of the past three years were:

(In millions, except %)

Capital

Percent of total capital expenditures

Compliance: (1)

Operating and maintenance

Remediation (2)

Total

(1) Based on the American Petroleum Institute’s definition of environmental expenditures.

(2) These amounts include spending charged against remediation reserves and exclude non-cash accruals for environmental remediation.

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We accrue for environmental remediation activities when the responsibility to remediate is probable and the amount of associated costs can be reasonably estimated. As environmental remediation matters proceed toward ultimate resolution or as additional remediation obligations arise, charges in excess of those previously accrued may be required.

New or expanded environmental requirements, which could increase our environmental costs, may arise in the future. We believe we comply with all legal requirements regarding the environment, but since not all of them are fixed or presently determinable (even under existing legislation) and may be affected by future legislation or regulations, it is not possible to predict all of the ultimate costs of compliance, including remediation costs that may be incurred and penalties that may be imposed.

Our environmental capital expenditures are expected to approximate $92 million in 2026. 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 and could increase if additional projects are identified or additional requirements are imposed.

For more information on environmental regulations that impact us, or could impact us, see Item 1. Business – Regulatory Matters and Item 1A. Risk Factors.

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

The preparation of financial statements in accordance with GAAP requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities as of the date of the consolidated financial statements and the reported amounts of revenues and expenses during the respective reporting periods. Accounting estimates are considered to be critical if (i) the nature of the estimates and assumptions is material due to the levels of subjectivity and judgment necessary to account for highly uncertain matters or the susceptibility of such matters to change and (ii) the impact of the estimates and assumptions on financial condition or operating performance is material. Actual results could differ from the estimates and assumptions used. See Item 8. Financial Statements and Supplementary Data – Note 2 for additional information on these policies and estimates, as well as a discussion of additional accounting policies and estimates.

Fair Value Estimates

Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. There are three approaches for measuring the fair value of assets and liabilities: the market approach, the income approach and the cost approach, each of which includes multiple valuation techniques. The market approach uses prices and other relevant information generated by market transactions involving identical or comparable assets or liabilities. The income approach uses valuation techniques to measure fair value by converting future amounts, such as cash flows or earnings, into a single present value amount using current market expectations about those future amounts. The cost approach is based on the amount that would currently be required to replace the service capacity of an asset. This is often referred to as current replacement cost. The cost approach assumes that the fair value would not exceed what it would cost a market participant to acquire or construct a substitute asset of comparable utility, adjusted for obsolescence.

The fair value accounting standards do not prescribe which valuation technique should be used when measuring fair value and do not prioritize among the techniques. These standards establish a fair value hierarchy that prioritizes the inputs used in applying the various valuation techniques. Inputs broadly refer to the assumptions that market participants use to make pricing decisions, including assumptions about risk. Level 1 inputs are given the highest priority in the fair value hierarchy while Level 3 inputs are given the lowest priority. The three levels of the fair value hierarchy are as follows:

• Level 1 - Observable inputs that reflect unadjusted quoted prices for identical assets or liabilities in active markets as of the measurement date. Active markets are those in which transactions for the asset or liability occur in sufficient frequency and volume to provide pricing information on an ongoing basis.

• Level 2 - Observable market-based inputs or unobservable inputs that are corroborated by market data. These are inputs other than quoted prices in active markets included in Level 1, which are either directly or indirectly observable as of the measurement date.

• Level 3 - Unobservable inputs that are not corroborated by market data and may be used with internally developed methodologies that result in management’s best estimate of fair value.

Valuation techniques that maximize the use of observable inputs are favored. Assets and liabilities are classified in their entirety based on the lowest priority level of input that is significant to the fair value measurement. The assessment of the significance of a particular input to the fair value measurement requires judgment and may affect the placement of assets and liabilities within the levels of the fair value hierarchy. We use an income or market approach for recurring fair value measurements and endeavor to use the best information available. We use a cost method or income approach for non-recurring fair value measurements related to the valuation of our leased assets and assets acquired in business combinations. See Item 8. Financial Statements and Supplementary Data – Note 15 for disclosures regarding our fair value measurements.

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Significant uses of fair value measurements include:

• assessment of impairment of long-lived assets, intangible assets, goodwill and equity method investments;

• assessment of values for assets in implicit leases, including sales-type leases;

• assessment of values for underlying assets to record net investment in sales-type leases;

• recorded values for assets acquired and liabilities assumed in connection with acquisitions; and

• recorded values of derivative instruments.

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 volumes and associated cash flows, and apply an appropriate discount rate; the cost approach, which may require estimates of replacement costs, reproduction 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 Item 8. Financial Statements and Supplementary Data – Note 4 for additional information on our acquisitions. See Item 8. Financial Statements and Supplementary Data – Note 15 for additional information on fair value measurements.

Impairment Assessments of Long-Lived Assets, Intangible Assets, Goodwill and Equity Method Investments

Fair value calculated for the purpose of testing our long-lived assets, intangible assets, goodwill and equity method investments for impairment is estimated using the expected present value of future cash flows method and comparative market prices when appropriate. Significant judgment is involved in performing these fair value estimates since the results are based on forecasted financial information prepared using significant assumptions including:

• Future operating performance. Our estimates of future operating performance are based on our analysis of various supply and demand factors, which include, among other things, industry-wide capacity, our planned utilization rate, end-user demand, capital expenditures and economic conditions, as well as commodity prices. Such estimates are consistent with those used in our planning and capital investment reviews.

• Future volumes. Our estimates of future throughput of crude oil, natural gas, NGL and refined product volumes are based on internal forecasts and depend, in part, on assumptions about our customers and other producers’ drilling activity which is inherently subjective and contingent upon a number of variable factors (including future or expected crude oil and natural gas pricing considerations), many of which are difficult to forecast. Management considers these volume forecasts and other factors when developing our forecasted cash flows.

• Discount rate commensurate with the risks involved. We apply a discount rate to our cash flows based on a variety of factors, including market and economic conditions, operational risk, regulatory risk and political risk. This discount rate is also compared to recent observable market transactions, if possible. A higher discount rate decreases the net present value of cash flows.

• Future capital requirements. These are based on authorized spending and internal forecasts.

Assumptions about the macroeconomic environment are inherently subjective and difficult to forecast. We base our fair value estimates on projected financial information which we believe to be reasonable. However, actual results may differ from these projections.

The need to test for impairment can be based on several indicators, including a significant reduction in prices of or demand for commodities, a poor outlook for profitability, a significant reduction in pipeline throughput volumes, a significant reduction in natural gas or NGL volumes processed, other changes to contracts or changes in the regulatory environment in which the asset or equity method investment is located.

Long-lived Asset Impairment Assessments

Long-lived assets used in operations are assessed for impairment whenever changes in facts and circumstances indicate that the carrying value of the assets may not be recoverable based on the expected undiscounted future cash flow of an asset group. For purposes of impairment evaluation, long-lived assets must be grouped at the lowest level for which independent cash flows can be identified, which is at least at the reporting unit level and in some cases for similar assets in the same geographic region

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where cash flows can be separately identified. If the sum of the undiscounted cash flows is less than the carrying value of an asset group, fair value is calculated, and the carrying value is written down if greater than the calculated fair value.

Goodwill Impairment Assessments

Unlike long-lived assets, goodwill must be tested for impairment at least annually, and between annual tests if an event occurs or circumstances change that would more likely than not reduce the fair value of a reporting unit below its carrying amount. Goodwill is tested for impairment at the reporting unit level. We have five reporting units, four of which have goodwill allocated to them. A goodwill impairment loss is measured as the amount by which a reporting unit’s carrying value exceeds its fair value, without exceeding the recorded amount of goodwill.

At December 31, 2025, MPLX had four reporting units with goodwill totaling approximately $8.8 billion. For the annual impairment assessment as of November 30, 2025, management performed only qualitative assessments for all four reporting units as we determined it was more likely than not that the fair values of the reporting units exceeded their carrying values. See Item 8. Financial Statements and Supplementary Data – Note 14 for additional information relating to our reporting units and goodwill.

Equity Method Investment Impairment Assessments

Equity method investments are assessed for impairment whenever factors indicate an other-than-temporary loss in value. Factors providing evidence of such a loss include the fair value of an investment that is less than its carrying value, absence of an ability to recover the carrying value or the investee’s inability to generate income sufficient to justify our carrying value. At December 31, 2025, we had $4.8 billion of equity method investments recorded on the Consolidated Balance Sheets.

An estimate of the sensitivity to net income resulting from impairment calculations is not practicable, given the numerous assumptions (e.g., pricing, volumes and discount rates) that can materially affect our estimates. That is, unfavorable adjustments to some of the above listed assumptions may be offset by favorable adjustments in other assumptions.

See Item 8. Financial Statements and Supplementary Data – Note 5 for additional information on our equity method investments.

Leases

In accounting for leases, we analyze new or modified leases for lease classification. One of the key inputs into the lease classification analysis is the fair value of the leased assets. For newly classified sales-type leases, the net investment in the lease is recorded at the estimated fair value of the underlying leased assets. Significant assumptions used to estimate the leased assets’ fair value include market information for comparable assets, discount rates, forecasted cash flows and cost estimates to replace the service capacity of an asset.

See Item 8. Financial Statements and Supplementary Data – Note 21 for additional information on our leases.

Contingent Liabilities

We accrue contingent liabilities for legal actions, claims, litigation, environmental remediation, tax deficiencies related to operating taxes and third-party indemnities for specified tax matters when such contingencies are both probable and estimable. We regularly assess these estimates in consultation with legal counsel to consider resolved and new matters, material developments in court proceedings or settlement discussions, new information obtained as a result of ongoing discovery and past experience in defending and settling similar matters. Actual costs can differ from estimates for many reasons. For instance, settlement costs for claims and litigation can vary from estimates based on differing interpretations of laws, opinions on degree of responsibility and assessments of the amount of damages. Similarly, liabilities for environmental remediation may vary from estimates because of changes in laws, regulations and their interpretation, additional information on the extent and nature of site contamination and improvements in technology.

We generally record losses related to these types of contingencies as cost of revenues or selling, general and administrative expenses on the Consolidated Statements of Income, except for tax deficiencies unrelated to income taxes, which are recorded as other taxes.

An estimate of the sensitivity to net income if other assumptions had been used in recording these liabilities is not practical because of the number of contingencies that must be assessed, the number of underlying assumptions and the wide range of reasonably possible outcomes, in terms of both the probability of loss and the estimates of such loss.

For additional information on contingent liabilities, see Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations – Environmental Matters and Compliance Costs and Item 8. Financial Statements and Supplementary Data – Note 22.

Accounting Standards Not Yet Adopted

Refer to Item 8. Financial Statements and Supplementary Data – Note 3 to our audited consolidated financial statements for recently issued financial accounting pronouncements.

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