China National Offshore Oil Corporation, or CNOOC Group, is the third-largest national oil company in China, after CNPC and China Petrochemical Corporation. The CNOOC Group focuses on the exploitation, exploration and development of crude oil and natural gas in offshore China, along with its subsidiary COOEC.

The China National Petroleum Corporation (CNPC) is a major national oil and gas corporation of China and one of the largest integrated energy groups in the world. Its headquarters are in Dongcheng District, Beijing. CNPC was ranked fourth in 2022 Fortune Global 500, a global ranking of the largest corporations by revenue.