Covering 75,000 square miles, the Permian Basin is the second-largest oilfield in the world. No single company owns all this land. The 5 top-producing oil companies in the Permian Basin in 2020 were: Pioneer Natural Resources (107,649,132 barrels), Diamondback E&P (81,624,452 barrels), XTO Energy (64,419,198 barrels), COG Operating (63,184,150 barrels), and Parsley Energy Operations (49,864,918 barrels). The 5 top-producing gas companies in the Permian Basin in 2020 were: Cimarex Energy (210,594,099 cubic feet), Apache (202,067,095 cubic feet), Anadarko E&P (199,387,733 cubic feet), Chevron (161,136,611 cubic feet), and EOG Resources (127,219,543 cubic feet).