Edward S. Jacob

Society of Petroleum Engineers, Inc. provides petroleum engineering services. The non-profit company is based in Allen, TX and has subsidiaries in United States, India and Canada.

American Petroleum Institute (API) is the only national trade association that represents all aspects of America's oil and natural gas industry. Its more than 400 corporate members, from the largest major oil company to the smallest of independents, come from all segments of the industry. They are producers, refiners, suppliers, pipeline operators and marine transporters, as well as service and supply companies that support all segments of the industry.

Keen Energy Services LLC engages in the contract drilling of onshore oil and natural gas wells for exploration and production companies. The company was founded in 1991 and is headquartered in Stillwater, OK.

Grey Wolf, Inc. provides contract oil and gas land drilling services. The company was founded in 1980 and is headquartered in Houston, TX.

Bayard Drilling Technologies, Inc. engages in the provision of land drilling services. The company was founded on December 13, 1996 and is headquartered in Oklahoma City, OK.

Helmerich & Payne International Drilling Co. drills oil and gas wells. It operates as a contract drilling company, owns land rigs, platform rigs located in the Gulf of Mexico and other International rigs. The company was founded in 1967 and is headquartered in Tulsa, OK.