Chesapeake Energy Corporation, established in 1989 and headquartered in Oklahoma City, Oklahoma, operates as an American independent energy company. Its core business involves the discovery, extraction, and development of crude oil, natural gas, and natural gas liquids (NGLs) from subterranean deposits throughout the United States. The company maintains a significant presence in key natural gas resource regions, including: The Marcellus Shale, located in Pennsylvania's Northern Appalachian Basin.