| Name of entity                                             |   | Our interest |   | Jurisdiction of incorporation |
|------------------------------------------------------------|--------|--------------|--------|-------------------------------|
|                                                       |   |         |   |                          |
| CNOOC China Limited                                        |   | 100%         |   | Tianjin, PRC             |
| CNOOC International Limited                                |   | 100%         |   | British Virgin Islands   |
| China Offshore Oil (Singapore) International Pte Ltd  |   | 100%         |   | Singapore                |
| CNOOC Finance (2002) Limited                               |   | 100%         |   | British Virgin Islands   |
| CNOOC Finance (2003) Limited                               |   | 100%         |   | British Virgin Islands   |
| Malacca Petroleum Limited                                  |   | 100%         |   | Bermuda                  |
| OOGC America, Inc.                                         |   | 100%         |   | Delaware, USA            |
| OOGC Malacca Limited                                       |   | 100%         |   | Bermuda                  |
| CNOOC Southeast Asia Limited                               |   | 100%         |   | Bermuda                  |
| CNOOC Africa Holding Ltd.                                  |   | 100%         |   | British Virgin Islands   |
| CNOOC Africa Ltd.                                          |   | 100%         |   | British Virgin Islands   |
| CNOOC Africa (UK) Limited                                  |   | 100%         |   | London, U.K.             |
| CNOOC ONWJ Ltd.                                            |   | 100%         |   | Labuan, F.T.,Malaysia    |
| CNOOC SES Ltd.                                             |   | 100%         |   | Labuan, F.T.,Malaysia    |
| CNOOC Poleng Ltd.                                          |   | 100%         |   | Labuan, F.T.,Malaysia    |
| CNOOC Madura Ltd.                                          |   | 100%         |   | Labuan, F.T.,Malaysia    |
| CNOOC Blora Ltd.                                           |   | 100%         |   | Labuan, F.T.,Malaysia    |
| CNOOC NWS Private Limited                                  |   | 100%         |   | Singapore                |
| CNOOC Australia E&P Pty Ltd                            |   | 100%         |   | Australia                |
| CNOOC Wiriagar Holding Limited                        |   | 100%         |   | British Virgin Islands        |

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| CNOOC Muturi Holding Limited                            |   | 100%   |   | British Virgin Islands       |
|--------------------------------------------------------------|--------|--------|--------|------------------------------|
| CNOOC Muturi Limited                                         |   | 100%   |   | The Isle of Man         |
| CNOOC Canada Limited                                         |   | 100%   |   | Canada                  |
| CNOOC Belgium BVBA                                           |   | 100%   |   | Belgium                 |
| CNOOC Australia Limited                                      |   | 100%   |   | British Virgin Islands  |
| CNOOC Exploration & Production Nigeria Limited      |   | 100%   |   | Nigeria                 |
| AERD Projects Nigeria Limited                           |   | 92.11% |   | Nigeria                 |
| CNOOC Hong Kong Holding Limited                         |   | 100%   |   | Hong Kong                    |
| CNOOC Myanmar Holding Ltd.                              |   | 100%   |   | British Virgin Islands       |
| CNOOC Myanmar Ltd.                                           |   | 100%   |   | British Virgin Islands  |
| CNOOC Middle East (Qatar) Limited                       |   | 100%   |   | British Virgin Islands  |
| CNOOC Congo SA                                          |   | 100%   |   | Republic of Congo            |
| CNOOC Caspian (Kazakhstan) Ltd.                         |   | 100%   |   | Cayman Islands               |
| CNOOC Singapore Private Limited                              |   | 100%   |   | Singapore                    |
|                                                         |   |   |   |                         |
| CNOOC Australia Energy Pty Ltd                          |   | 100%   |   | Australia                    |
| CNOOC Batanghari Ltd.                                   |   | 100%   |   | Malaysia                     |
| CNOOC Palung Aru Ltd.                                   |   | 100%   |   | Malaysia                     |
| CNOOC FPSO Holding Limited                              |   | 100%   |   | Liberia                      |
| CNOOC Liberia Limited                                   |   | 100%   |   | Liberia                      |
| CNOOC Uganda (BVI) Ltd                                  |   | 100%   |   | British Virgin Islands       |
| De coöperatieve vereniging CNOOC Netherlands U.A.  |   | 100%   |   | The Netherlands              |
| CNOOC Netherlands B.V.                                  |   | 100%   |   | The Netherlands              |
| CNOOC Uganda Ltd                                        |   | 100%   |   | Uganda                       |
| CNOOC Deepwater Development Limited                          |   | 100%   |   | Zhuhai, PRC             |

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| CNOOC Iraq Limited                                    |   | 100% |   | British Virgin Islands       |
|------------------------------------------------------------|--------|------|--------|------------------------------|
| CNOOC Finance (2011) Limited                          |   | 100% |   | British Virgin Islands       |
| Tainan-Chaoshan Petroleum Operating Company Limited*  |   | 50%  |   | British Virgin Islands       |
| Husky Oil (Madura) Ltd.*                              |   | 50%  |   | British Virgin Islands  |
| Chaoyang Petroleum (BVI) Limited*                     |   | 50%  |   | British Virgin Islands  |
| Chaoyang Petroleum (Trinidad) Block 3A Limited*       |   | 50%  |   | Barbados                     |
| Chaoyang Petroleum (Trinidad) Block 2C Limited*       |   | 50%  |   | Barbados                     |
| Sunrise Angola Petroleum Holding Limited*             |   | 50%  |   | Cayman Islands               |
| Bridas Corporation*                                   |   | 50%  |   | British Virgin Islands       |

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