Biography

Mr. Holderness has served as a director of Diamondback since February 2025. Mr. Holderness previously served on the board of Rock Solid Lifestyles, Inc. from September 2016 to April 2024. He was also a founder and served as Chief Financial Officer of P&A Exchange LLC from March 2021 to December 2023. Prior to that, Mr. Holderness served on the board of Ranger Oil Corporation (formerly “Penn Virginia Corporation”) from September 2016 to October 2021 where he was appointed chairman of the Audit Committee and then Chairman of the Board from February 2018 until January 2021. Mr. Holderness served as the Chief Financial Officer of ProPetro Holding Corp. from October 2019 to November 2020. Prior to his time at ProPetro, Mr. Holderness served as an advisor to Concho Resources Inc. from May 2016 to January 2017 following his employment at Concho where he served as the Senior Vice President, Chief Financial Officer and Treasurer from August 2008 to May 2016. Before Concho, Mr. Holderness served in various roles in the energy industry including Senior Vice President and Chief Financial Officer of Eagle Rock Energy Partners, Vice President and Chief Accounting Officer of Pioneer Natural Resources Company, Vice President and Chief Financial Officer of Basic Energy Services, Inc., and Vice President and Controller of Pure Resources, Inc. He began his career at KPMG in May 1986 after earning a Bachelor of Business Administration in Accounting degree from Boise State University and is a Certified Public Accountant. Mr. Holderness currently serves on the board of JMR Services LLC.