CNOOC Limited is an investment holding company. The Company is principally engaged in the exploration, development, production and sale of crude oil, natural gas and other petroleum products. The Company operates through three segments: exploration and production, trading business and corporate. The Company is engaged in the upstream operating activities of the conventional oil and gas, shale oil and gas, oil sands and other unconventional oil and gas business. The Company's core operation areas are Bohai, Western South China Sea, Eastern South China Sea and East China Sea in offshore China. Overseas, the Company has oil and gas assets in Asia, Africa, North America, South America, Oceania and Europe.