Warren Petroleum Co Limited Partnership

Southwestern Energy Company, founded in 1929, explores, produces and distributes natural gas and oil throughout the United States, including Arkansas, Texas, Louisiana, New Mexico, and Oklahoma. The company conducts its exploration and production activities through its wholly owned subsidiaries, Southwestern Energy Production Company and SEECO. It has oil drilling operations in the Arkoma Basin and East Texas, and exploration facilities in New Mexico. The company s subsidiary, Arkansas Western Gas Company, distributes and transmits natural gas to more than 1 million residential, commercial and industrial customers in northern Arkansas. It also provides natural gas storage and transportation facilities to third-party clients. Southwestern Energy Company is headquartered in Houston.

With an estimated 2.3 billion barrels of proved reserves, Anadarko Petroleum Corporation is one of the largest independent oil exploration and production companies in the world. The company also markets approximately 3 billion cubic feet of natural gas per day throughout the United States and Canada. Anadarko s operational focus in North America extends from the Gulf of Mexico up through the Canadian Rockies and onto the north slope of Alaska. Its international operations are focused on major positions in Algeria, Venezuela and Qatar, as well as exploration or production operations in several other countries. James T. Hackett has been the chief executive officer of Anadarko Petroleum for more than two years. He has been with the petroleum and natural gas company for over two years. Hackett earned a BS degree from the University of Illinois, and a MBA from Harvard. Headquartered in The Woodlands, Texas, Anadarko Petroleum Corporation employs approximately 3,400 people in locations throughout the world.

Enterprise Products Partners is a publicly traded energy partnership and a North American provider of midstream energy services to producers and consumers of natural gas, natural gas liquids and crude oil. The company transports its products through more than 32,500 miles of onshore and offshore pipelines. Enterprise Products Partners has a portfolio of assets that includes pipelines, storage, drilling platforms and natural gas processing. The company s onshore natural gas pipeline systems provide for the gathering and transmission of natural gas in Alabama, Colorado, Louisiana, Mississippi, New Mexico and Texas, as well as from onshore developments, such as the San Juan and Permian supply basins, and from offshore developments in the Gulf of Mexico. In 2006, the company purchased the Pioneer silica gel natural gas processing plant, located in Opal, Wyo., from TEPPCO Partners. Enterprise Products Partners is headquartered in Houston.