Can CNOOC only invoice itself?

No, according to the public information inquired, all commodity invoices are issued by sales merchants, and the invoices issued are legal and valid. When the cardholder recharges in the business hall of CNOOC, he can directly issue an electronic invoice with the on-site assistance of the staff. China Offshore Oil Corporation (English name: China National Offshore Oil Corporation) is a super-large state-owned enterprise (central enterprise) directly under the State-owned Assets Supervision and Administration Commission of the State Council, China.