Mr. David J. Butters serves as the Chairman, Chief Executive Officer and President of Navigator Gas Transport, PLC. Mr. Butters has been the Chairman, Chief Executive Officer and President of Navigator Holdings Ltd. since September 2008. He served as Managing Director of Lehman Brothers Inc., a subsidiary of Lehman Brothers Holdings, Inc. from 1969 to September 2008. He serves as the Chairman of Energy Ventures Inc. He served as the Chairman of Gulfmark Offshore, Inc. until November 14, 2017 and its Independent Director since 1989 until November 14, 2017. He served as the Chairman of the Board of Gulfmark International Inc. Mr. Butters served as Vice Chairman and Presiding Director at Weatherford International plc. He has been an Independent Director of Weatherford International plc since 1984. He has been a Director of Weatherford International, LLC since 1989. He serves as a Director of Navigator Holdings Ltd. He serves as a Director of BT Shipping Ltd., Anangel-American Shipholding and Acol Tankers Ltd. He has been a Director of Grant Prideco, Inc. since December 2001. He serves as a Member of the Board of Advisors of Energy International N. V. He served as a Director of GulfMark International Inc. from 1989 to May 1, 1997. He served as a Director of TransMontaigne LLC from October 9, 2003 to July 1, 2004 and Lehman Brothers Holdings, Inc. Mr. Butters holds a B.S. from Boston College and an M.B.A. from Columbia University Business School.