Scott Sheffield

Evergreen Resources, Inc., located below the Western prairies and below the Rocky Mountains and the waters of the Gulf of Mexico. The exploration and production company, which has boosted its Gulf of Mexico properties, holds proved reserves oil equivalent. The vast majority of the exploration and production company's reserves are found within the US.

Pioneer Southwest Energy Partners LP was a master limited partnership, which owns and acquires oil and gas assets. The company's assets consist of non-operated working interests in producing wells in the Spraberry field in the Permian Basin of West Texas. Its area of operations consisted of onshore Texas and eight counties in the southeast region of New Mexico. Pioneer Southwest Energy Partners was founded in June 2007 and was headquartered in Irving, TX.

Pioneer Natural Resources Co. operates as an independent oil and gas exploration and production company. The firm engages in hydrocarbon exploration in the Cline Shale. It focuses on the operation of the Permian Basin, Eagle Ford Shale, Rockies, and West Panhandle projects. The company was founded by Scott Douglas Sheffield on April 2, 1997, and is headquartered in Irving, TX.