MPLX LP Declares Quarterly Distribution

FINDLAY, Ohio, Jan. 25, 2013 - The board of directors of MPLX LP (MPLX) declared a cash distribution of $0.1769 per common unit for the fourth quarter of 2012. This amount corresponds to the prorated minimum quarterly distribution of $0.2625 per unit, or $1.05 per unit on an annualized basis. The distribution will be paid Feb. 14, 2013, to unitholders of record Feb. 4, 2013. This release is intended to be a qualified notice under Treasury Regulation Section 1.1446-4(b). Brokers and nominees should treat 100 percent of MPLX's distributions to foreign investors as being attributable to income that is effectively connected with a United States trade or business. Accordingly, MPLX's distributions to non-United States investors are subject to federal income tax withholding at the highest applicable effective tax rate. # # # About MPLX LP MPLX is a fee-based, growth-oriented limited partnership recently formed by Marathon Petroleum Corporation to own, operate, develop and acquire pipelines and other midstream assets related to the transportation and storage of crude oil, refined product and other hydrocarbon-based products. Headquartered in Findlay, Ohio, MPLX's assets consist of a 51 percent interest in a network of common carrier crude oil and products pipeline assets located in the Midwest and Gulf Coast regions of the United States and a 100 percent interest in a butane storage cavern located in West Virginia. Additional information about MPLX LP may be found on its website at www.mplx.com. Investor Relations Contacts: Pamela Beall (419) 429-5640 Beth Hunter (419) 421-2559 MPLX LP Quarterly Distribution: http://hugin.info/155038/R/1673274/544685.pdf This announcement is distributed by Thomson Reuters on behalf of Thomson Reuters clients. The owner of this announcement warrants that: (i) the releases contained herein are protected by copyright and other applicable laws; and (ii) they are solely responsible for the content, accuracy and originality of the information contained therein. Source: MPLX LP via Thomson Reuters ONE [HUG#1673274]