X0206 3 2012-10-24 1 0001552000 MPLX LP MPLX 0001521085 Shaffner George P. C/O MPLX LP 200 E. HARDIN STREET FINDLAY OH 45840 0 1 0 0 VP and Chief Operating Officer Exhibit List: Exhibit 24 - Power of Attorney Mr. Shaffner is the Vice President and Chief Operating Officer of MPLX GP LLC, the general partner of the Issuer. The Issuer is managed by the directors and executive officers of MPLX GP LLC. /s/ Molly R. Benson, Attorney-in-Fact for George P. Shaffner 2012-10-24