MPLX LP is a diversified large cap master limited partnership formed by MPC in 2012 that owns and operates midstream energy infrastructure and logistics assets and provides fuels distribution services. Its 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 and natural gas and NGL treating processing and fractionation facilities positioned throughout the United States.

MPLX LP generates revenue primarily through tariffs for gathering and transporting crude oil refined products other hydrocarbon based products and renewables through its pipelines and barge docks. It also earns fees for storing crude oil refined products and renewables at its storage facilities. The marine business generates revenue under a fee based capacity contract with MPC. The fuels distribution business provides scheduling and marketing services for MPC s products and earns revenue based on the volume of MPC s products sold each month. Additionally the company operates pipelines owned by MPC or in joint interest and receives operating fees for those assets. In the Natural Gas and NGL Services segment revenue comes from gathering treating processing and transportation of natural gas and NGLs as well as transportation fractionation storage and marketing of NGLs and from product sales related to NGL transactions.

The company operates through the following segments: Crude Oil and Products Logistics and Natural Gas and NGL Services.

• Crude Oil and Products Logistics includes the gathering transportation storage and distribution of crude oil refined products other hydrocarbon based products and renewables; its assets consist of 14,853 miles of wholly and jointly owned pipelines refining logistics at 13 refineries 88 terminals including rail and truck racks one export terminal storage caverns tank farm assets an inland marine business and a fuels distribution business; revenue is generated by charging tariffs for pipeline transport fees for storage marine fee based capacity contracts fuels distribution fees based on MPC s product volumes and operating fees for pipelines operated for MPC or joint interest.

• Natural Gas and NGL Services gathers treats processes and transports natural gas; transports fractionates stores and markets NGLs; as of December 31 2025 the segment had approximately 9.4 Bcf per day of gas gathering capacity 11.2 Bcf per day of natural gas processing capacity and 819 mbpd of fractionation and de ethaneization capacity; it also owns or operates about 1,401 miles of NGL pipelines; revenue is earned from fee based percent of proceeds keep whole and purchase arrangements product sales from NGL transactions and services provided under various contract types with producers and third parties.

MPLX LP holds a strong position in the US midstream energy sector due to its extensive asset base and its strategic relationship with MPC which is one of the largest refiners in the country. The company benefits from long term fee based contracts minimum volume commitments and fee for capacity arrangements that provide stable and predictable cash flows. Competitors in the Crude Oil and Products Logistics segment include independent terminal and pipeline companies integrated petroleum companies refining and marketing companies distribution companies and wholesale petroleum distributors. In the Natural Gas and NGL Services segment competitors consist of other natural gas midstream providers major integrated oil companies independent exploration and production companies interstate and intrastate pipelines and marine and land based transporters of natural gas and NGLs. MPLX LP s competitive advantages include its access to both NGL and natural gas markets its critical connections to MPC s refining infrastructure its strategic gathering and processing agreements with key producers and the long term nature of many of its contracts which together support durable cash flow growth and cost competitiveness.

The company s primary customer is MPC which supplied approximately 48 percent of total revenues and other income in 2025 mainly through the Crude Oil and Products Logistics segment. In addition MPLX LP serves a broad range of producer customers operating in crude oil and natural gas resource plays including the Marcellus Shale Permian Basin Utica Shale STACK Shale and Bakken Shale among others. The Natural Gas and NGL Services segment also derives revenue from various third party customers in the Southwest and Marcellus regions whose specific names are not disclosed in the filing.