Southwestern Energy Company, an independent energy company, engages in the exploration, development, and production of natural gas, oil, and natural gas liquids (NGLs) in the United States. It operates through two segments: Exploration and Production, and Marketing. The company focuses on the development of unconventional natural gas and oil reservoirs located in Pennsylvania, Ohio, and West Virginia. As of December 31, 2020, it had approximately 217,296 net acres in Northeast Appalachia; and approximately 571,922 net acres in Southwest Appalachia. The company's estimated proved natural gas, oil, and NGLs reserves comprise 11,990 billion cubic feet of natural gas equivalent (Bcfe); and 2,437 Bcfe of proved undeveloped reserves. It also engages in marketing and transportation of natural gas, oil, and NGLs. It serves energy companies, utilities, and industrial purchasers of natural gas. Southwestern Energy Company was incorporated in 1929 and is headquartered in Spring, Texas.