C. Johnson

Ultra Petroleum Corp. engages in the development, production, operation, exploration, and acquisition of oil and natural gas properties. It focuses on developing a tight gas sand trend located in the Green River Basin of southwest Wyoming; and assessing, exploring, and developing its position in the Marcellus Shale and other horizons located in the north-central Pennsylvania area of the Appalachian Basin of Pennsylvania. The company was founded on November 14, 1979 and is headquartered in Englewood, CO.

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.

Anadarko Petroleum Corp. is an independent exploration and production company. It operates through the following segments: Exploration and Production; WES Midstream; and Other Midstream. The Exploration and Production segment focuses on the exploration, development, production, and sale of oil and natural gas. The WES Midstream and Other Midstream segment consists of gathering, compressing, treating, processing, and transporting of natural gas; gathering, stabilizing, and transporting of oil and natural gas liquids. The company was founded in 1959 and is headquartered in The Woodlands, TX.