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Executive Officers

  • Stephen Chazen - President, Chief Executive Officer and Chairman

    Stephen Chazen has served as our Chief Executive Officer and President since February 2017 and has served as Chairman of the TPGE Board following the completion of the IPO in May 2017. Mr. Chazen retired as Chief Executive Officer of Occidental in April 2016. He began his career at Occidental in 1994 as Executive Vice President—Corporate Development. He was named Chief Financial Officer in 1999 and served in that position until 2010. Mr. Chazen was appointed President of Occidental in 2007. He was then named Chief Operating Officer in 2010 before being appointed Chief Executive Officer in May 2011. Mr. Chazen was elected to the Board of Directors in 2010. Before joining Occidental, Mr. Chazen was Managing Director in Corporate Finance and Mergers and Acquisitions at Merrill Lynch. He worked as Director of Project Evaluation and Reservoir Engineering at Columbia Gas Development Corporation from 1977 to 1982. Mr. Chazen began his career at Northrop Corporation in 1973 as Laboratory Manager at the Johnson Space Center, where he worked until 1977.


    Mr. Chazen is a former Chairman of the American Petroleum Institute. He also serves on the Board of Advisors of Rice University’s Baker Institute for Public Policy and is a member of the Senior Cabinet of the President’s Leadership Council at Houston Methodist Hospital. Mr. Chazen also serves as a Director on the boards of directors of the Methodist Hospital Research Institute, Ecolab Inc., The Williams Companies, Inc., and the Catalina Island Conservancy and is a member of the Board of Regents of the University of Houston. Mr. Chazen holds a Ph.D. in Geology from Michigan State University, a master’s degree in Finance from the University of Houston and a bachelor’s degree in Geology from Rutgers College.

  • Christopher Stavros – Executive Vice President and Chief Financial Officer

    Christopher Stavros serves as Executive Vice President and our Chief Financial Officer. Mr. Stavros has more than 25 years of experience in energy and financial industries. He most recently served as Senior Vice President and Chief Financial Officer of Occidental. Mr. Stavros joined Occidental in 2005 and was named Chief Financial Officer in 2014 having previously served as Vice President, Investor Relations and Treasurer. Mr. Stavros retired from Occidental in May 2017. Prior to joining Occidental in 2005, Mr. Stavros was a Senior Analyst at UBS with coverage of the Oil and Gas sector.


    Mr. Stavros received his BSBA from Boston University and received his MBA from the University of Rochester.

  • Timothy D. Yang - Executive Vice President, General Counsel, and Secretary

    Timothy D. Yang joined Magnolia Oil & Gas Corporation as Executive Vice President, General Counsel and Secretary in September 2018. Prior to joining Magnolia, Mr. Yang served as General Counsel and Corporate Secretary of Newfield Exploration Company from July 2015 through September 2018. Prior to Newfield, Mr. Yang served as Senior Vice President, Land & Legal, General Counsel, Chief Compliance Officer and Secretary of Sabine Oil & Gas Corporation from December 2014 to July 2015 and as Senior Vice President, General Counsel, Chief Compliance Officer and Secretary from February 2013 to December 2014. His legal experience also covers both public and private companies within the energy and investment industries including Invesco Ltd./AIM Investments, Pogo Producing Company, and Eagle Rock Energy Partners, L.P. Mr. Yang holds a Bachelor of Arts in Biology from Trinity University, obtained his Juris Doctor from the University of Houston Law Center and is a member of the Texas and Kansas state bar associations.


  • Arcilia Acosta - Director (Independent)

    Arcilia Acosta has served as a director since May 10, 2017. Ms. Acosta is the President and Chief Executive Officer of CARCON Industries & Construction, specializing in commercial, institutional and transportation construction, and is also the Chief Executive Officer and controlling principal of STL Engineers. Ms. Acosta serves on the board of directors of Legacy Texas Financial Group, Inc., Energy Future Holdings Corp., the Texas Higher Education Coordinating Board, and the Dallas Citizens Council. Ms. Acosta previously served on the national advisory board for BBVA Compass Bank and the Texas Tech National Alumni Association.

    Ms. Acosta received a Bachelor of Arts from Texas Tech University and Board Director Certification from Southern Methodist University Southwest School of Banking and is a Graduate of the Harvard University

    Ms. Acosta chairs the Governance committee and sits on the Compensation committee.

  • Angela Busch - Director (Independent)

    Angela Busch currently serves as the Senior Vice President of Corporate Development for Ecolab Inc. where she is responsible for acquisitions, divestitures and alliances in support of Ecolab’s strategic objectives related to its global portfolio of business and activities. Ms. Busch has held this position since 2006. Prior to joining Ecolab, Busch held several positions related to strategy development and acquisition work including most recently Managing Director, Merger and Acquisitions Group at RBC Capital Markets. She previously held positions in Mergers and Acquisitions and Planning and Business Development at Honeywell and Land O’Lakes. Ms. Busch was also previously a management consultant at McKinsey & Company, where she focused on strategic initiatives for clients in the healthcare industry.

    Ms. Busch holds a bachelor’s degree in Mechanical Engineering from the University of Minnesota Institute of Technology, a Master’s in Management from the Kellogg School of Management and a Juris Doctorate from Northwestern University School of Law.

    Ms. Busch serves on the Audit and Governance committees.

  • Edward Djerejian - Director (Lead Independent)

    Edward Djerejian has served as a director since May 10, 2017. Ambassador Djerejian served in the U.S. Foreign Service for eight presidents, from John F. Kennedy in 1962 to William J. Clinton in 1994. Prior to his nomination by President Clinton as U.S. ambassador to Israel in which he served from 1993-1994, he was assistant secretary of state for Near Eastern affairs in both the George H.W. Bush and the Clinton administrations from 1991 to 1993. He was the U.S. ambassador to the Syrian Arab Republic from 1988 to 1991. He also served as special assistant to President Ronald Reagan and deputy press secretary for foreign affairs in the White House from 1985 to 1986.

    After his retirement from government service in 1994, he became, and currently serves as, the director of the James A. Baker III Institute for Public Policy at Rice University. He has been awarded the Presidential Distinguished Service Award, the Department of State’s Distinguished Honor Award and numerous other honors, including the Ellis Island Medal of Honor and the Anti-Defamation League’s Moral Statesman Award. He is also a recipient of the Association of Rice Alumni’s Gold Medal. In 2011, Ambassador Djerejian was elected a fellow of the American Academy of Arts and Sciences. He is also a member of the Board of Trustees of the Carnegie Corporation of New York.

    Ambassador Djerejian previously served as Chairman of the Board and a director of Occidental until 2015, and as a director of Baker Hughes Incorporated and Global Industries, Ltd., where he was Chairman of the Governance Committee. He currently serves on the board of directors of The Mexico Fund, Inc. He holds a Bachelor of Science and a Doctor of Humane Letters, honoris causa, from Georgetown University, as well as a Doctor of Laws, honoris causa, from Middlebury College.

    Mr. Djerejian serves on the Compensation and Governance committees and is the Lead Independent Director.

  • John B. Walker - Director

    John B. Walker has served as the Chief Executive Officer of EnerVest, Ltd since 1992. EnerVest has more than $7 billion in assets with an interest in more than 40,000 wells across 14 states. During his time on Wall Street, Mr. Walker was selected by Institutional Investor as an “All-American” energy analyst for six years in a row. In November 2007, Mr. Walker received the oil and gas industry’s highest honor, the Chief Roughneck Award. Mr. Walker served the Independent Petroleum Association of America (IPAA) as Chairman from 2003-2005. Mr. Walker previously served as Chairman of the Board of Stewards of Chapelwood United Methodist Church and Chairman of the Board of Directors of the Sam Houston Area Council of the Boy Scouts of America. During his time with the Boy Scouts of America, Mr. Walker was received the Distinguished Eagle Award in May 2007 and the Silver Beaver Award in 2001. Mr. Walker is a member of the National Petroleum Council and All-American Wildcatters. Mr. Walker previously served on the Board of Regents of the Texas Tech University System from January 2012 to January 2015 and was re-appointed to a six-year term in January 2017. In November 2015, Mr. Walker was named as a National Finalist for the EY Entrepreneur of the Year and, prior to that, he was named Distinguished Alumni at Texas Tech University in 2004. Mr. Walker served on the board of PetroLogistics LP from 2012 until 2014. Mr. Walker also held multiple roles at EV Management, LLC, the general partner of EV Energy GP, L.P., which is the former general partner of EV Energy Partners, L.P., including Executive Chairman from 2012 to June 2018, Chief Executive Officer from 2006 to 2012 and director from 2002 to June 2018.


    Mr. Walker holds a BBA (with honors) from Texas Tech University and an MBA (with distinction) from New York University.

  • Dan F. Smith - Director (Independent)

    Dan F. Smith has served as a director since May 10, 2017. Mr. Smith is a retired Chief Executive Officer of Lyondell Chemical Company, or “Lyondell,” and its wholly owned subsidiaries Millennium Chemicals Inc. and Equistar Chemicals, LP., a position he held from December 1996 until his retirement in December 2007. From June 2007 to December 2007, Mr. Smith was also Chairman of Lyondell. Mr. Smith began his career as an engineer with Atlantic Richfield Company in 1968. He was elected President of Lyondell in August 1994 and Chief Executive Officer in December 1996.

    Mr. Smith is a director of Orion Engineered Carbons, S.A., Kraton Corp., the general partner of Valerus Compression Services, L.P. (doing business as Axip Energy Services, L.P.) and Nexeo Solutions, Inc. During the past five (5) years, Mr. Smith served on the board of directors of Northern Tier Energy GP LLC and Cooper Industries plc. He also serves as a member of the College of Engineering Advisory Council at Lamar University.

    Mr. Smith is a graduate of Lamar University with a B.S. degree in chemical engineering.

    Mr. Smith chairs the Compensation committee and sits on the Audit committee.

  • Michael MacDougall - Director

    Michael MacDougall has served as a director since May 10, 2017. Mr. MacDougall is a senior partner of TPG, the Managing Partner of TPG Pace Energy and the co-Managing Partner of TPG Energy Solutions. Mr. MacDougall joined TPG in 2002 as a principal and was elected as a partner of TPG and joined the firm’s private equity investment committee in 2004. From 2002 through 2017, Mr. MacDougall was responsible at different times for building and leading the firm’s global private equity investing efforts for each of the Industrial sector and the Energy and Natural Resources sector. Since 2008, Mr. MacDougall focused primarily on Energy and Natural Resources investing for the firm and served as the head or co-head of the firm’s global Energy and Natural Resources private equity investing efforts. Most recently, Mr. MacDougall has led the firm’s efforts focusing on expanding TPG’s Energy sector investing capabilities beyond its traditional private equity business by playing a leadership role in forming TPG Energy Solutions, an investment business focused on providing structured growth equity capital to high quality midstream and upstream oil & gas companies, and by expanding the TPG Pace Group’s industry focus with the formation of TPG Pace Energy.


    Prior to joining TPG in 2002, Mr. MacDougall was a vice president in the Principal Investment Area of the Merchant Banking Division of Goldman, Sachs & Co., where he focused on private equity and mezzanine investments. He is a director of Harvester Holdings, LLC, Jonah Energy Holdings LLC, and is a director of the general partner of Valerus Compression Services, L.P. (doing business as Axip Energy Services, L.P.). He is also a member of the board of directors of the Baylor College of Medicine Board of Trustees and The University of Texas Development Board. Mr. MacDougall received his BBA, with highest honors, from The University of Texas at Austin and received his MBA, with distinction, from Harvard Business School. Mr. MacDougall is well-qualified to serve as a director because of his significant directorship experience, his experience in the global Energy and Natural Resources sector, and his transactional experience with a number of different companies at TPG. Over the last five (5) years, Mr. MacDougall previously served on the board of directors of the following publicly traded companies: Copano Energy, L.L.C., Graphic Packaging Holding Company and Northern Tier Energy GP LLC.

  • James R. Larson - Director (Independent)

    James R. Larson has served as an independent director of CSI Compressco GP Inc., general partner of CSI Compressco L.P., and as Chairman of its Audit Committee since July 2011 and as a member of its Conflicts Committee since April 2012. Since January 1, 2006, Mr. Larson has been retired. From September 2005 until January 1, 2006, Mr. Larson served as senior vice president of Anadarko Petroleum Corporation (“Anadarko”). From December 2003 to September 2005, Mr. Larson served as Senior Vice President, Finance and Chief Financial Officer of Anadarko. From 2002 to 2003, Mr. Larson served as Senior Vice President, Finance of Anadarko, where he oversaw treasury, investor relations, internal audits and acquisitions and divestitures. From 1995 to 2002, Mr. Larson served as Vice President and Controller of Anadarko where he was responsible for accounting, financial reporting, budgeting, forecasting, and tax. Prior to that, he held various tax and financial positions within Anadarko after joining the company in 1981. Mr. Larson is a current member of the American Institute of Certified Public Accountants, Financial Executives International, and the Tax Executives Institute. Mr. Larson also served on the Board of Directors of EV Management, LLC, the general partner of EV Energy GP, L.P., which is the former general partner of EV Energy Partners, L.P., a Houston-based publicly traded limited partnership engaged in acquiring, producing, and developing oil and gas properties, from September 2006 until June 2018. He received his B.B.A. degree in business from the University of Iowa.

    Mr. Larson has over 30 years of experience in the oil and natural gas business, and has served as Chief Financial Officer of a large independent oil and natural gas company.

    Mr. Larson chairs the Audit committee and sits on the Governance committee.