|Plains Exploration & Production Company (PXP) is an independent energy company engaged in the upstream oil and gas business. The upstream business acquires, develops, explores for and produces oil and gas. Its upstream activities are located in the United States. PXP owns oil and gas properties with principal operations in Onshore California, Offshore California, the Gulf Coast Region, the Gulf of Mexico and the Rocky Mountains. As of December 31, 2011, it had estimated proved reserves of 410.9 million barrels of oil equivalent of which 59% was comprised of oil and 55% was proved developed. It has a total proved reserve life of approximately 12 years and a proved developed reserve life of approximately seven years. As of December 31, 2011, it had working interests in 3,190 gross (2,879 net) active producing oil wells and 1,423 gross (209 net) active producing gas wells. In December 2011, the Company completed the divestment of its Texas Panhandle properties to Linn Energy, LLC.