ConocoPhillips is an international, integrated energy company. As of Dec. 31, 2010, it is the third-largest U.S. integrated energy company, based on market capitalization, as well as proved reserves and production of oil and natural gas, and the largest refiner in the United States. ConocoPhillips is the seventh-largest holder of proved reserves and the fourth-largest refiner worldwide, of nongovernment-controlled companies.