Sinopec Oilfield Service : RESIGNATION OF EMPLOYEE REPRESENTATIVE SUPERVISOR

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Sinopec Oilfield Service Corporation

(a joint stock limited company established in the People's Republic of China)

(Stock code: 1033)

RESIGNATION OF EMPLOYEE REPRESENTATIVE SUPERVISOR

The Board and all its directors guarantee that this announcement does not contain any false information, misleading statement or material omission, and severally and jointly accept responsibility for the authenticity, accuracy and completeness of the contents of this announcement.

The supervisory committee of Sinopec Oilfield Service Corporation (the "Company") announces that it has accepted the resignation of Mr. Chen Weiguo ("Mr. Chen") from his position as an employee representative supervisor of the Company due to change of work arrangement on 6 August 2020. According to the articles of association of the Company, Mr. Chen's resignation takes effect upon the submission of the resignation letter to the supervisory committee of the Company on 6 August 2020.

Mr. Chen has confirmed that he has no disagreement with the board of directors and the supervisory committee of the Company, and there are no other matters in relation to his resignation that need to be brought to the attention of the shareholders of the Company.

By Order of the Board

Li Honghai

Secretary to the Boardy

Beijing, PRC, 7 August 2020

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As at the date of this announcement, the Board of Directors comprises Mr. Chen Xikun#, Mr. Yuan Jianqiang#, Mr. Lu Baoping+, Mr. Fan Zhonghai+, Mr. Wei Ran+, Ms. Jiang Bo*, Mr. Chen Weidong* and Mr. Dong Xiucheng*.

• Non-ExecutiveDirector
  # Executive Director
  * Independent Non-Executive Director

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