Pioneer Management

Mathew S. Porter, President and Chief Executive Officer
Mr. Porter was appointed as a director of our Board upon our emergence from Chapter 11 in May 2020. In July 2020, he was appointed our Interim Chief Executive Officer under a consulting arrangement until December 31, 2020 when he was appointed our President and Chief Executive Officer, at which time he also became an employee of Pioneer. He currently serves as a non-independent director of our Board. Mr. Porter is also a founding partner at Activos, LLC, a consulting company in the domestic and international oilfield service industry and Allied Industrial Partners, an investment firm that focuses on investments in manufacturing, distribution, energy and industrial service companies. Previously, he was a chief executive officer, president and director at Xtreme Drilling Corp. and chief financial officer at Bronco Drilling Company. He started his career at BOK Financial Corp. as portfolio manager. Mr. Porter received his Master of Business Administration degree and Bachelor's Degree in Business Administration from University of Oklahoma. .
Lorne E. Phillips, Executive Vice President and Chief Financial Officer
Mr. Phillips was appointed executive vice president and chief financial officer in February 2009. Prior to joining Pioneer, Mr. Phillips worked for 10 years at Cameron International Corp., serving most recently as vice president and treasurer. Prior to that, he was general manager of Cameron's Canadian valves operations, vice president of marketing and M&A for the valves division, and business development manager for Cameron. Before joining Cameron, he was a financial analyst for SCF Partners, a provider of equity capital to energy service and equipment companies, and for Simmons & Company International, an investment bank focused on the energy industry.
Brian L. Tucker, Executive Vice President and Chief Operating Officer
Mr. Tucker was appointed Chief Operating Officer effective January 1, 2019.  Since joining Pioneer in 2012, Mr. Tucker has served as our Senior Vice President Drilling, then as President of our Drilling Services Business 2015-2018, and as President of Drilling and Well Servicing  April -December 2018. Prior to joining Pioneer, Mr. Tucker was a Vice President for Helmerich and Payne (H&P) managing the South Texas operations from 2010 to 2012. From 2004 to 2010, Mr. Tucker served as drilling engineer and operations manager for the Barnett Shale, South Texas and West Texas operations for H&P. Mr. Tucker served eight years as an officer in the U.S. Army, is a West Point graduate with a Bachelor of Science in Systems Engineering, and completed the Harvard Business School Advanced Management Program in 2014. He currently serves as a board member of Catholic Charities Archdiocese of San Antonio.
Bryce Seki, Vice President, General Counsel, Secretary and Compliance Officer 
Mr. Seki joined the Company in May of 2011, first serving as Corporate Counsel and then Associate General Counsel before being promoted to Vice President - Associate General Counsel in May 2016. Prior to joining the Company, Mr. Seki was an associate attorney at Fulbright & Jaworski L.L.P. (now known as Norton Rose Fulbright). Mr. Seki received a Bachelor of Arts from the University of Notre Dame and a Doctor of Jurisprudence from Notre Dame Law School.