John Clarke has served as director since July 2019 and as Chairman of the Board since November 2023. Mr. Clarke currently serves as a partner and member of the advisory board of Turnbridge Capital, LLC, a private equity firm investing in companies focused primarily on energy services and equipment and infrastructure, a position that he has held since 2011. From 2004 through 2009, Mr. Clarke served as the chief executive officer and executive chairperson of NATCO Group, Inc. ( NATCO ), a publicly traded oilfield equipment manufacturer and related services provider. During a two decade period beginning in the mid-1970s, Mr. Clarke served as the Chief Financial Officer or otherwise as a senior executive in several large, publicly-traded, energy-related companies, including Transco Energy Company, The Houston Exploration Company, Cabot Oil & Gas Corp., and Dynegy Inc. Mr. Clarke also served as a Managing Director of Simmons & Company from 1996 to 1997. Previously, Mr. Clarke has served as a director of Glori Energy, Inc. from 2011 to 2015, Tesco Corporation from 2011 to 2013 and Penn Virginia Corporation from 2009 to 2016. Mr. Clarke earned a B.A. in Economics from the University of Texas and a M.B.A. from Southern Methodist University. Mr. Clarke brings to the Board a wealth of managerial experience in publicly traded companies, including as both a chief executive officer and chief financial officer.