China BlueChemical Ltd. — Proxy Solicitation & Information Statement 2026

Apr 13, 2026

NOC

中海石油化学股份有限公司 China BlueChemical Ltd.*

(a joint stock limited company incorporated in the People's Republic of China with limited liability)

(Stock Code: 3983)

Proxy Form for Domestic Shareholders' Class Meeting

Number of shares related to this proxy form (note 1)	domestic shares of the Company (the “Domestic Shares”)

I/(We) (note 2)

of

being the holder(s) of

Domestic Shares of China BlueChemical Ltd.

(the "Company") now appoint (note 3) (I.D. No.:)

of

or failing him, the Chairman of the meeting as my (our) proxy to attend and vote for me (us) on the resolution in accordance with the instructions below and on my (our) behalf at the class meeting for shareholders of the Domestic Shares (the "Domestic Shareholders' Class Meeting") to be held at the 3rd Floor Meeting Room, Yihai International, Haikou, the PRC on Thursday, 28 May 2026 immediately after the H shares shareholders' class meeting of the Company for the purpose of considering and, if thought fit, passing the resolution as set out in the notice convening the said meeting.

By way of Special Resolution		For (note 4)	Against (note 4)
1.	To consider and approve the granting of a general mandate to the board of directors of the Company to repurchase overseas listed foreign shares of the Company.

Date: 2026

Signature: (note 5)

Notes:

(1) Please insert the number of shares registered in your name(s) to which the proxy relates. If no number is inserted, this form of proxy will be deemed to relate to all the shares in the capital of the Company registered in your name(s).

(2) Please insert the full name(s) (in Chinese or in English, as shown in the register of members) and registered address(es) in BLOCK LETTERS.

(3) A shareholder entitled to attend and vote at the class meeting may appoint one or more proxies to attend and vote in his/her stead. A proxy need not be a shareholder of the Company. Where a shareholder has appointed more than one proxy to attend the class meeting, such proxies may only vote on a poll.

The instrument appointing a proxy must be in writing under the hand of a shareholder or his/her attorney duly authorised in writing. If the shareholder is a corporation, that instrument must be either under its common seal or under the hand of its attorney or duly authorised attorney(s). If that instrument is signed by an attorney of the shareholder, the power of attorney authorising that attorney to sign or other authorisation document must be notarised.

In order to be valid, this proxy form together with the power of attorney or other authorisation document (if any) must be deposited at the Company's Secretary Office of the Board in China (Address: Room 1707, Kaikang CNOOC Mansion, No. 15, Sanqu, Anzhenxili, Chaoyang District, Beijing, the PRC) not less than 24 hours before the time fixed for holding the Domestic Shareholders' Class Meeting by holders of Domestic Shares (the "Domestic Shareholders"). Completion and return of this proxy form will not preclude Domestic Shareholder from attending and voting in person at the Domestic Shareholders' Class Meeting if she/he so wishes.

(4) IMPORTANT: IF YOU WISH TO VOTE FOR ANY RESOLUTION, TICK IN THE BOX MARKED “FOR”. IF YOU WISH TO VOTE AGAINST ANY RESOLUTION, TICK IN THE BOX MARKED “AGAINST”. Failure to tick the box will entitle your proxy to cast your vote at his/her discretion. Your proxy will also be entitled to vote at his/her discretion on the resolution properly put to the Domestic Shareholders' Class Meeting other than those referred to in the notice convening the Domestic Shareholders' Class Meeting.

(5) Domestic Shareholders who intend to attend the meeting in person or by proxy should return the reply slip in person, by post or by fax to Company's Secretary Office of the Board in China on or before Friday, 8 May 2026. The address of the Company's Secretary Office of the Board in China is Room 1707, Kaikang CNOOC Mansion, No. 15, Sanqu, Anzhenxili, Chaoyang District, Beijing, the PRC (Tel: 0086-10-84527250, Fax: 0086-10-84527254, Post code: 100029).

(6) For full text of the above resolution, please refer to the notice of the Domestic Shareholders' Class Meeting dated 13 April 2026.

(7) Domestic Shareholders or their proxies must present proof of their identities upon attending the Domestic Shareholders' Class Meeting. Should a proxy be appointed, the proxy must also present copies of his/her proxy form, or copies of appointing instrument and power of attorney, if applicable.

(8) The Domestic Shareholders' Class Meeting is expected to last not more than one day. Domestic Shareholders or proxies attending the Domestic Shareholders' Class Meeting are responsible for their own transportation and accommodation expenses.

• For identification purpose only