China Oilfield Services : NOTICE OF 2021 FIRST CLASS MEETING OF THE HOLDERS OF H SHARES

Hong Kong Exchanges and Clearing Limited and The Stock Exchange of Hong Kong Limited take no responsibility for the contents of this announcement, make no representation as to its accuracy or completeness and expressly disclaim any liability whatsoever for any loss howsoever arising from or in reliance upon the whole or any part of the contents of this announcement.

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

(Stock Code: 2883)

NOTICE OF 2021 FIRST CLASS MEETING OF

THE HOLDERS OF H SHARES

NOTICE IS HEREBY GIVEN that a class meeting of the holders of H Shares (the "H Shareholders' Class Meeting") of China Oilfield Services Limited (the "Company") will be held at Room 311, Main Building of COSL, 201 Haiyou Avenue, Yanjiao Economic & Technological Development Zone, Sanhe City, Hebei Province, China, at 10:30 a.m. Tuesday, 1 June 2021 for the purpose of considering and, if thought fit, passing the following resolutions:

AS SPECIAL RESOLUTION

To consider and, if thought fit, to approve the following general mandate to buy back domestic shares (A shares) and overseas-listed foreign invested shares (H shares):

1. approve a general mandate to the board of directors to, by reference to market conditions and in accordance with needs of the Company, buy back domestic shares (A shares) not exceeding 10% of the total number of domestic shares (A shares) in issue at the time when this resolution is passed at annual general meeting and the relevant resolutions are passed at class meetings of shareholders. Pursuant to PRC laws and regulations, in the case of buy back of A shares to be canceled to reduce the registered capital, the Board of the Company will seek further approval from its shareholders in general meeting for each buy back of domestic shares (A shares) even where the general mandate is granted, but will not be required to seek shareholders' approval at class meetings of domestic share (A share) shareholders or overseas-listed foreign invested share (H share) shareholders.
2. approve a general mandate to the board of directors to, by reference to market conditions and in accordance with needs of the Company, buy back overseas-listed foreign invested shares (H shares) not exceeding 10% of the total number of overseas-listed foreign invested shares (H shares) in issue at the time when this resolution is passed at the annual general meeting and the relevant resolutions are passed at class meetings of shareholders.

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1. the board of directors be authorised to (including but not limited to the following):
2. 1. determine time of buy back, period of buy back, buy back price and number of shares to buy back, etc;
   2. notify creditors and issue announcements;
   3. open overseas share accounts and to carry out related change of foreign exchange registration procedures;
   4. carry out relevant approval procedures and to carry out filings with the China Securities Regulatory Commission; and
   5. carry out cancelation procedures for buy back shares, make corresponding amendments to the Articles of Association of the Company relating to share capital and shareholdings etc, carry out modification Registrations, and to deal with any other documents and matters related to share buy back.
3. The above general mandate will expire on the earlier of ("Relevant Period"):
4. 1. the conclusion of the annual general meeting of the Company for 2021;
   2. the expiration of a period of twelve months following the passing of this special resolution at the annual general meeting for 2020, the first A Shareholders' Class Meeting in 2021 and the first H Shareholders' Class Meeting in 2021; or
   3. the date on which the authority conferred by this resolution is revoked or varied by a special resolution of shareholders at a general meeting, or a special resolution of shareholders at a class meeting of domestic share (A share) shareholders or a class meeting of overseas-listed foreign invested share (H share) shareholders,

except where the board of directors has resolved to buy back domestic shares (A shares) or overseas-listed foreign invested shares (H shares) during the Relevant Period and the share buy back is to be continued or implemented after the Relevant Period.

By Order of the Board of

China Oilfield Services Limited

Wu Yanyan

Company Secretary

14 April 2021

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As at the date of this announcement, the executive directors of the Company are Messrs. Qi Meisheng (Chairman) and Zhao Shunqiang; the non-executive directors of the Company are Messrs. Xu Yugao and Zhao Baoshun; and the independent non-executive directors of the Company are Messrs. Fong Chung, Mark, Wong Kwai Huen, Albert and Lin Boqiang.

Notes:

1. All resolutions at the meeting will be taken by poll pursuant to the Listing Rules and the results of the poll will be published on the Stock Exchange's and the Company's websites in accordance to the Hong Kong Listing Rules.
2. H Share shareholders whose names appear on the Company's register of members maintained by Computershare Hong Kong Investor Services Limited on 13 May 2021 (Thursday) are entitled to attend and vote at the H Share Class Meeting.
3. H Share shareholders who intend to attend the H Share Class Meeting must complete and return the written replies for attending the H Share Class Meeting to the Company's Hong Kong registered office by facsimile or post no later than 12 May 2021 (Wednesday):

Address: 65/F., Bank of China Tower

1 Garden Road, Hong Kong

Tel: [phone]

Fax: [phone]

1. Each shareholder of the Company who has the right to attend and vote at the H Share Class Meeting is entitled to appoint in writing one or more proxies, whether a shareholder of the Company or not, to attend and vote on his behalf at the H Share Class Meeting. Where a shareholder of the Company has appointed more than one proxy to attend the H Share Class Meeting, such proxies may only vote on a poll. The instrument appointing a proxy must be in writing under the hand of the appointor or his attorney duly authorised in writing. In the case that an appointer is a legal person, the power of attorney must be either under the common seal of the legal person or under the hand of its director or other person, duly authorised. If the instrument appointing a proxy is signed by an attorney of the appointor, the power of attorney authorising that attorney to sign, or other documents of authorisation, must be certified by a notary public. For H Share shareholders, the power of attorney or other documents of authorisation and forms of proxy must be delivered to the Company's registered office at 17M Floor, Hopewell Centre, 183 Queen's Road East, Wanchai, Hong Kong by post or facsimile, no less than 24 hours before the time appointed for the holding of the H Share Class Meeting in order for such documents to be valid. For A Share shareholders, the above-mentioned documents must be delivered to the planning and finance department of the Company before the above-mentioned time.
2. H Share shareholders whose names appear on the Company's register of members maintained by Computershare Hong Kong Investor Services Limited after office hour on 13 May 2021 are entitled to attend the H Share Class Meeting. The Company's register of members will be closed from 13 May 2021 (Thursday) to 1 June 2021 (Tuesday) (both days inclusive), during which time no transfer of shares will be registered. Transferees of H Shares who wish to attend the H Share Class Meeting must deliver their duly stamped instruments of transfer, accompanied by the relevant share certificates, to Computershare Hong Kong Investor Services Limited by no later than 4:30 p.m. on 12 May 2021 (Wednesday) for completion of the registration of the relevant transfer in accordance with the Articles of Association of the Company.

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The address of Computershare Hong Kong Investor Services Limited is as follows: Shops 1712-1716

17th Floor, Hopewell Centre 183 Queen's Road East Wanchai

Hong Kong

1. Shareholders or their proxies must present proof of their identities upon attending the H Share Class Meeting. Should a proxy be appointed, the proxy must also present copies of his/her form of proxy, or copies of appointing instrument and power of attorney, if applicable.
2. Shareholders or proxies attending the H Share Class Meeting are responsible for their own transportation and accommodation expenses.

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