Pamela K. M. Beall Elected Director and Appointed President of the General Partner of MPLX LP

FINDLAY, Ohio, Dec. 16, 2013 - MPLX LP (NYSE: MPLX) announced that Pamela K. M. Beall has been elected to the board of directors of its general partner and will serve as its president, both effective Jan. 1, 2014. Ms. Beall is currently vice president of Investor Relations. Timothy T. Griffith, vice president and treasurer, will assume responsibility for Investor Relations. # # # About MPLX LP MPLX is a fee-based, growth-oriented master limited partnership formed in 2012 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 products and other hydrocarbon-based products. Headquartered in Findlay, Ohio, MPLX's assets consist of a majority equity 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. For additional information about the company, please see our website at Investor Relations Contacts: Beth Hunter (419) 421-2559 Geri Ewing (419) 421-2071 Media Contacts: Angelia Graves (419) 421-2703 Beall Elected Director and Appointed President: This announcement is distributed by GlobeNewswire on behalf of GlobeNewswire 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 GlobeNewswire [HUG#1750306]