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Mark H. Kleinman

Mark H. Kleinman
Mark H. Kleinman

Executive Vice President and General Counsel

Mark Kleinman joined Pioneer Natural Resources in June 2005 as Vice President, Corporate Secretary and Chief Compliance Officer, and in January 2014, he was named Senior Vice President and General Counsel. In 2019, he was named Executive Vice President and General Counsel. He serves as a member of the Pioneer Management Committee.

As General Counsel, Kleinman is responsible for all aspects of Pioneer’s legal function and supports the Pioneer Board of Directors.

Kleinman began his career in 1986 as an associate with the Dallas-based law firm of Jackson Walker L.L.P. He served as Assistant General Counsel of Sterling Software, Inc., a NYSE company supplying computer software and services worldwide, from 1996 through its acquisition in 2000 by Computer Associates International, Inc., and as Vice President and General Counsel of Inet Technologies, Inc., a NASDAQ-traded global provider of communications software products, from 2000 through its acquisition in 2004 by Tektronics, Inc.

Kleinman received his Juris Doctor, with honors, from the University of Texas School of Law, where he served on the editorial board of the Texas Law Review. He graduated with a Bachelor of Arts in Government from The University of Texas.

He is a member of the State Bar of Texas, and he served on the New York Stock Exchange Commission on Corporate Governance, which issued its final report in 2010.