Shanghai Junshi Biosciences : OVERSEAS REGULATORY ANNOUNCEMENT - SHANGHAI JUNSHI BIOSCIENCES CO., LTD.* ANNOUNCEMENT ON ADDITION OF ESTIMATED EXTERNAL GUARANTEE QUOTA FOR 2021

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SHANGHAI JUNSHI BIOSCIENCES CO., LTD.*

上海君實生物醫藥科技股份有限公司

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

(Stock code: 1877)

OVERSEAS REGULATORY ANNOUNCEMENT

This announcement is made pursuant to Rule 13.10B of the Rules Governing the Listing of Securities on The Stock Exchange of Hong Kong Limited.

Reference is made to the "Shanghai Junshi Biosciences Co., Ltd.* Announcement on Addition of Estimated External Guarantee Quota for 2021" published by Shanghai Junshi Biosciences Co., Ltd.* on the website of the Shanghai Stock Exchange, for reference purpose only. The following is a translation of the official announcement solely for the purpose of providing information. Should there be any discrepancies, the Chinese version will prevail.

By order of the Board

Shanghai Junshi Biosciences Co., Ltd.*

Mr. Xiong Jun

Chairman

Shanghai, the PRC, 30 March 2021

As at the date of this announcement, the Board of the Company comprises Mr. Xiong Jun, Dr. Li Ning, Dr. Feng Hui, Mr. Zhang Zhuobing and Dr. Yao Sheng as executive Directors; Dr. Wu Hai, Mr. Tang Yi, Mr. Li Cong, Mr. Yi Qingqing and Mr. Lin Lijun as non-executive Directors; and Dr. Chen Lieping, Mr. Qian Zhi, Mr. Zhang Chun, Dr. Jiang Hualiang and Dr. Roy Steven Herbst as independent non-executive Directors.

• For identification purpose only

Stock Code: 688180

Stock Abbreviation: Junshi Bio Announcement No.: Lin 2021-025

Shanghai Junshi Biosciences Co., Ltd.*

Announcement on Addition of Estimated External

Guarantee Quota for 2021

The Board of Directors and all Directors of the Company warrant that the contents of the announcement do not contain any false misleading statement or material omission, and shall undertake legal liabilities in accordance with the law for the truthfulness, accuracy and completeness of the contents herein.

Important reminder:

• Name of the guaranteed party:

Shanghai Junshi Biotechnology Co., Ltd.* (hereinafter "Junshi Biotechnology"), a wholly-owned subsidiary of the Company.

• Amount of the guarantee:

In 2021, the Company proposes to add an estimated external guarantee quota by an amount not exceeding RMB1.5 billion. As of 31 December 2020, the total amount of external guarantee provided by Company was RMB1,000 million, of which the actual balance of guarantee for its wholly-owned subsidiary, Junshi Biotechnology was RMB900 million, and the unused quota within the approved guarantee quota was RMB100 million.

• No counter-guarantee has been provided for this guarantee.
• This matter needs to be submitted to the Company's 2020 annual general meeting for consideration.

1. Overview of the Guarantee

1. Overview of the situation

In order to meet the capital needs of the Company and its subsidiaries for production, operation and business development, taking into account the Company's 2021 development plan, in 2021, the Company and its wholly-owned subsidiary, Suzhou Union Biopharm Biosciences Co., Ltd.* (hereinafter "Suzhou Union Biopharm") intend to provide external guarantee for its wholly-owned subsidiary, Junshi Biotechnology when there is the need to apply for credit and for daily operation, and the total amount of guarantees shall not exceed RMB1.5 billion. Details such as the specific amount, period and fee rate of the guarantee shall be determined by the Company, Junshi Biotechnology and financial institutions such as the lending bank within the aforementioned quota through negotiation. For matters relating to the guarantee, the officially-signed guarantee documents shall prevail. The use of banking credit under the guarantee, and/or the projects involved, should conform to the Company's approved business plan, and be performed and corresponding approvals shall be obtained in accordance with the provisions of the Company's articles of association.

The Board of Directors of the Company has requested the general meeting to authorise the chairman of the Board of Directors of the Company and persons authorised by the chairman to, within the scope of the aforementioned guarantee quota, handle the specific matters for providing the guarantee within 12 months upon the approval of the general meeting according to the needs of the Company's actual operating conditions.

(2) Review and approval procedures

At the thirty-fourth meeting of the second session of the Board of Directors and the twenty-sixth meeting of the second session of the Board of Supervisors held on 30 March 2021, the Company considered and approved the "Resolution on Addition of Estimated External Guarantee Quota for 2021". The independent non-executive

directors have provided express independent opinion of consent on this matter, and this resolution needs to be submitted to the Company's 2020 annual general meeting for consideration.

II. General Information of the Guaranteed Party

(1) General information

Name of the company: Shanghai Junshi Biotechnology Co., Ltd.*

Date of incorporation: 29 June 2016

Place of registration: Room 1203, Block 2, Lane 1800, Xinyang Road, Lingang New Area, China (Shanghai) Pilot Free Trade Zone

Legal representative: Feng Hui

Scope of business: Engaging in technical services, technical consulting, technology development, and technology transfer in the fields of biotechnology and biopharmaceutical technology, as well as the import and export of goods and technologies. [Projects that are subject to approval according to law may only be carried out upon approval by relevant departments.]

Relationship with the Company: A wholly-owned subsidiary of the Company, the Company holds 100% of its shares

Key financial data: At the end of 2020, Junshi Biotechnology had total assets of RMB2,411,682,300, total liabilities of RMB1,656,822,100, and net assets of RMB754,860,100. In 2020, Junshi Biotechnology recorded annual operating revenue of RMB114,560,400 and net profit of RMB-80,257,300. After deducting non-recurring gains and losses, its net profit was RMB-113,243,000. The above financial data for 2020 has been audited by RSM China (Special General Partnership). Junshi Biotechnology is legally existing in accordance with the law, is not a dishonest

person subject to enforcement, has good capacity for the performance of contracts.

III. Main content of the Guarantee Agreement

To date, except for the existing external guarantees with Junshi Biotechnology as the guaranteed party, the Company has not yet signed any relevant agreements with regard to new guarantees for 2021, and the above planned total amount of new guarantee shall be no more than the estimated guarantee quota that the Company intends to provide, and it will take effect after being submitted to the Company's general meeting for review and approval. When business actually occurs, the amount, period, fee rate and other details of the guarantee shall be determined by the Company, Suzhou Union Biopharm and Junshi Biotechnology with financial institutions such as the lending bank within the aforementioned quota through negotiation. For matters relating to the guarantee, the officially-signed guarantee documents shall prevail.

IV. Reasons for and Necessity of the Guarantee

Junshi Biotechnology, the Company's main production base for drugs under research, has good prospects for business development. The external guarantee to be provided by the Company this time is for the purpose of ensuring normal production and operation of its subsidiaries and the needs of the rapid development of project construction, as well as for the purpose of applying for credit by its subsidiaries and for their daily operation. The Company and relevant subsidiaries are operating in good condition, and the guarantee risks are controllable. There are no such circumstances that are detrimental to the interests of the Company and other shareholders, especially minority shareholders.

V. Opinion of the Board of Directors

At the thirty-fourth meeting of the second session of the Board of Directors held on 30 March 2021, the Company considered and passed the "Resolution on Addition of Estimated External Guarantee Quota for 2021". The Company's Board of Directors is of the view that the Company's addition of estimated external guarantee quota for 2021 has been determined after comprehensively taking into consideration the business development needs of the Company and its subsidiaries, and thus it is in line with the actual operating conditions and overall development strategy of the Company. The guaranteed party is a wholly-owned subsidiary of the Company, with good assets and credit, and the guarantee risks are controllable. The guarantee matters are in the interests of the Company and all shareholders.

The independent non-executive directors are of the view that the Company's addition of estimated external guarantee quota for 2021 was a reasonable estimate derived from the consideration of meeting the business needs of its wholly-owned subsidiaries to apply for credit and their daily operation needs, taking into account the Company's 2021 development plan, so as to ensure the orderly development of the Company's production and operation activities. The guaranteed subject within the quota listed was a Company's wholly-owned subsidiary included in its consolidated financial statements, which was compliant with relevant laws and regulations and the relevant provisions of the "Articles of Association" and the "Management Policies for External Guarantee of the Company". The review procedures were legal and valid, and the risks were controllable. It was in line with the interests of the Company, and there was no such circumstances that were harmful to the Company or other shareholders, especially the interests of minority shareholders. Therefore, the independent non-executive directors provided consent to the Company's addition of estimated external guarantee quota for 2021.

VI. Cumulative Amount of External Guarantees and Amount of Overdue Guarantees

As of the date of this announcement, the Company's total external guarantee amounted to RMB1,000 million, accounting for 17.16% and 12.50% of the latest audited net assets and total assets of the Company, respectively, of which, the actual balance of guarantee for its wholly-owned subsidiary, Junshi Biotechnology was RMB900 million, accounting for 15.44% and 11.25% of the latest audited net assets and total assets of the Company, respectively, and the unused quota within the approved guarantee quota was RMB100 million. As at the date of this announcement, the Company does not have overdue guarantees.

VII.	Documents Available for Inspection

1. Independent Opinions of Independent Non-executive Directors on Relevant Matters of the Thirty-fourth Meeting of the Company's Second Session of the Board of Directors of Shanghai Junshi Biosciences Co., Ltd.*
2. The most recent financial statements of the guaranteed party

Shanghai Junshi Biosciences Co., Ltd.*

Board of Directors

31 March 2021