MPLX LP is a fee-based limited partnership formed by Marathon Petroleum Corporation to own, operate, develop and acquire crude oil, refined product and other hydrocarbon-based product pipelines and other midstream assets. The Company�s assets consist of a 51% indirect interest in a network of common carrier crude oil and product pipeline systems and associated storage assets in the Midwest and Gulf Coast regions of the United States. The Company generates revenue by charging tariffs for transporting crude oil, refined products and other hydrocarbon-based products through its pipelines and at its barge dock and fees for storing crude oil and products at its storage facilities. The Company is also the operator of additional crude oil and product pipelines owned by Marathon Petroleum Corporation and its subsidiaries (MPC) and third parties, for which it is paid operating fees.