MPLX LP owns and operates midstream energy infrastructure and logistics assets primarily in the United States. It operates in two segments, Crude Oil and Products Logistics; and Natural Gas and NGL Services. The company is involved in the gathering, processing, and transportation of natural gas; gathering, transportation, fractionation, storage, and marketing of natural gas liquids; gathering, storage, transportation, and distribution of crude oil and refined products, as well as other hydrocarbon-based products and renewables; and sale of residue gas and condensate. It also engages in inland marine businesses, comprising fleet of boats and barges transport light products, heavy oils, crude oil, renewable fuels, chemicals, and feedstocks in the Mid-Continent and Gulf Coast regions, as well as a marine repair facility located on the Ohio River; and distribution of fuel, as well as operates refining logistics, terminals, rail facilities, and storage caverns.