MPLX is a master limited partnership (MLP) that owns and operates midstream energy infrastructure across the U.S. The business has two segments. Crude Oil and Products Logistics (~two-thirds of EBITDA) moves, stores, and distributes crude oil and refined products through roughly 14,900 miles of pipelines, 88 terminals, inland marine vessels, and refinery logistics assets. This segment is almost entirely captive to sponsor Marathon Petroleum (MPC), which owns ~64% of MPLX's common units and accounts for ~88% of segment revenues under long-term, fee-based contracts with minimum volume commitments. Natural Gas and NGL Services (~one-third of EBITDA, but growing) gathers, treats, processes, fractionates, and markets natural gas and NGLs, primarily in the Marcellus/Utica, Permian Basin, and Bakken. MPLX earns primarily fee-based revenues — tariffs per unit of volume transported, stored, or processed — meaning revenue is driven by throughput volumes rather than commodity prices, though some G&P contracts retain commodity exposure. MPLX's growth strategy centers on building an integrated "wellhead to water" NGL and gas value chain in the Permian, including new processing plants, sour gas treating capacity (via the ~$2.4B Northwind acquisition), NGL pipeline expansions, Gulf Coast fractionators, and an LPG export terminal JV with ONEOK. Appalachian capacity is also expanding. MPLX allocates capital by first sustaining operations, then growing its quarterly distribution (guided at 12.5% annual increases), then funding growth capex targeting mid-teens unlevered returns.