Ms. Mannen has served as President and Chief Executive Officer of both Marathon Petroleum Corporation, a leading, integrated, downstream energy company, and MPLX LP, a diversified, large-cap master limited partnership formed by Marathon Petroleum that owns and operates midstream energy infrastructure and logistics assets, and provides fuels distribution services, since August 2024. From January 2024 until August 2024, she was President of Marathon Petroleum. From 2021 to January 2024, she was the Executive Vice President and Chief Financial Officer of Marathon Petroleum. From 2017 to January 2021, she was the Executive Vice President and Chief Financial Officer of TechnipFMC (a successor to FMC Technologies, Inc.), a global leader in subsea, onshore/offshore, and surface projects for the energy industry. From 2014 to 2017, she served as Executive Vice President and Chief Financial Officer of FMC. Previously, Ms. Mannen served in several roles of increasing importance at FMC, including Senior Vice President and Chief Financial Officer. Prior to joining FMC in 1986, Ms. Mannen served as Finance Manager for Sheller-Globe Corporation. She currently serves on the Board of Directors of Marathon Petroleum and MPLX LP. Ms. Mannen also serves on the executive committee of the American Petroleum Institute, the executive committee of American Fuel and Petrochemical Manufacturers, and the executive committee of the Ohio Business Roundtable, and is a member of The Business Council.