CEO [CNOOC] FWP: Registration No. 333-188261 Registration No. 333-188261-01 Issuer Free
[Registration No. 333-188261 Registration No. 333-188261-01 Issuer Free Writing Prospectus dated May 2, 2013 Relating to Preliminary Prospectus Supplement dated May 1, 2013 CNOOC LIMITED Pricing Term Sheet 1.125% Notes due 2016 (the 2016 Notes) Issuer: CNOOC Finance (2013) Limited Guarantor: CNOOC Limited Principal Amount: US$750,000,000 May 9, 2016 Coupon: 1.125% Public Offering Price: 99.648% of principal amount Ranking: Senior]