Genscript Biotech Corporation — Share Issue/Capital Change 2026

Jun 4, 2026

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.

Genscript Biotech Corporation

(Incorporated in the Cayman Islands with limited liability)

(Stock code: 1548)

GRANT OF RESTRICTED SHARE UNITS

This announcement is made by the Board of the Company pursuant to Rule 17.06A, Rule 17.06B and Rule 17.06C of the Listing Rules. Unless otherwise defined herein, capitalized terms used in this announcement shall have the same meanings as defined in the Circular.

THE GRANT OF RESTRICTED SHARE UNITS PURSUANT TO THE 2021 RSU SCHEME

The Board announces that, on 4 June 2026, the Company granted an aggregate of 14,736,658 RSUs to four Directors, the rotating chief executive officer of the Company, certain employees and a service provider subject to acceptances as well as terms and conditions of the 2021 RSU Scheme.

Details of Grant of the RSUs

The details of the Grant are as follows:

Date of Grant: 4 June 2026

Number of the RSUs granted: 14,736,658 RSUs

Grantees:

(A) Director Grantees:

(a) 169,561 RSUs were granted to Mr. Robin Meng, being an executive Director of the Company;

(b) 113,041 RSUs were granted to Dr. Frank Zhang, being an executive Director of the Company;

(c) 113,041 RSUs were granted to Dr. Li Zhu, being an executive Director of the Company; and

(d) 113,041 RSUs were granted to Ms. Sally Wang, being an executive Director of the Company.

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(B) 841,470 RSUs were granted to Ms. Weihui Shao (“Ms. Sherry Shao”), the rotating chief executive officer of the Company.

(C) Employee Grantees: 13,356,351 RSUs were granted to certain employees of the Group.

(D) Service Provider Grantee: 30,153 RSUs were granted to an individual consultant, who is a service provider engaged by the Company to provide advisory and consulting services in relation to strategic development and operational management.

Having considered that (i) the Service Provider Grantee provides services to the Group on a continuing or recurring basis in the ordinary and usual course of business, (ii) the Service Provider Grantee has extensive experience in strategic and business management and the services provided are beneficial to the overall business development of the Group, and (iii) the RSUs granted to the Service Provider Grantee will be subject to a vesting period over three years, the Board believes that the grant can align the interests of the Service Provider Grantee with the interests of the Company and its Shareholders, motivate the Service Provider Grantee to commit to the Group’s future development and growth, which therefore is in line with the purpose of the 2021 RSU Scheme.

Purchase price for the RSUs granted: Nil

Market price of the Shares: The closing price per Share on the Stock Exchange on the Date of Grant is HK$12.99 per Share.

Vesting period: Subject to the terms of the Grant and the 2021 RSU Scheme:

(a) Director Grantees: the RSUs granted to Director Grantees will be subject to a total vesting period (i.e. the period between the Date of Grant and the last vesting date) of approximately three years in batches, where each batch of RSUs granted may vest annually starting from 31 August 2027 and will be fully vested on 31 August 2029.

(b) Ms. Sherry Shao: the RSUs granted to Ms. Sherry Shao will be subject to a total vesting period of approximately five years in batches, where each batch of RSUs granted may vest annually starting from 31 August 2027 and will be fully vested on 31 August 2031.

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(c) Employee Grantees:

(i) certain RSUs granted to one Employee Grantee will be subject to a total vesting period of approximately three years, with the first vesting date on 31 August 2026 and the remaining RSUs vesting annually starting from 31 August 2027, with full vesting on 31 August 2029. Such vesting arrangement adopts a mixed vesting schedule, where the RSUs may vest by several batches with the first batch to vest within twelve months of the date of grant and the last batch to vest three years after the date of grant. Such circumstance fall within those permitted under the 2021 RSU Scheme rules.

Having considered that (i) the first batch of the RSUs that may vest on 31 August 2026 shall be subject to clawback if the Employee Grantee ceases employment with the Company within one year from the date of commencement of employment, (ii) the majority of the RSUs granted to such Employee Grantee are subject to performance vesting criteria and a longer vesting period, and (iii) such grant incentivises and rewards the relevant Employee Grantee while encouraging his/her continued contribution to the operations, development and long-term success and growth of the Company, the Board believes that such a shorter vesting period between the date of grant and the first vesting date is appropriate and in line with the purpose of the 2021 RSU Scheme.

(ii) save as disclosed in above, the RSUs granted to other Employee Grantees will be subject to a total vesting period of approximately one to three years annually starting from 31 August 2027 and will be fully vested on 31 August 2029.

(d) Service Provider Grantee: the RSUs granted to the Service Provider Grantee will be subject to a total vesting period of approximately three years in batches, where each batch of RSUs granted may vest annually starting from 31 August 2027 and will be fully vested on 31 August 2029.

(a) Director Grantees: Vesting of each RSUs granted to Director Grantees shall be conditional upon the following criteria: (i) the achievement of certain performance targets, including without limitation, having met their respective key performance criteria, and (ii) compliance with the Company's code of conduct and practice of the corporate culture and core values. The Board is entitled to waive certain vesting conditions at its own discretion under specified circumstances as specified at the time of making the grant.

Performance targets:

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clawback mechanism:

(b) Ms. Sherry Shao: Vesting of each RSUs granted to Ms. Sherry Shao shall be conditional upon the following criteria: (i) the achievement of certain performance targets, including without limitation, having met her key performance criteria, and (ii) compliance with the Company’s code of conduct and practice of the corporate culture and core values. The Board is entitled to waive certain vesting conditions at its own discretion under specified circumstances as specified at the time of making the grant.

(c) Employee Grantees: Vesting of each RSUs granted to the Employee Grantees shall be conditional upon their achievement of the following criteria: (i) having met their respective key performance criteria; and (ii) compliance with the Company’s code of conduct and practice of the corporate culture and core values. The Board is entitled to waive certain vesting conditions at its own discretion under specified circumstances as specified at the time of making the grant.

(d) Service Provider Grantee: There is no performance target attached to the RSUs granted to the Service Provider Grantee.

(a) The RSUs granted to the Director Grantees, Ms. Sherry Shao and the Employee Grantees are subject to the clawback mechanism as set out in the terms of the 2021 RSU Scheme, pursuant to which the Board has the authority to provide that any award shall be subject to a clawback under specified circumstances as detailed in the 2021 RSU Scheme.

The Board is of the view that the flexibility given to the Board in relation to the clawback mechanism will allow the Company to claw back the equity incentives granted to the selected participants who committed serious misconduct or if there is a material misstatement in the audited financial statements of the Company that requires a restatement and therefore aligns with the purpose of the 2021 RSU Scheme.

(b) No clawback mechanism is attached to the RSUs granted to the Service Provider Grantee.

Financial assistance:

The Group has not provided any financial assistance to any of the Grantees facilitate the purchase of Shares under the 2021 RSU Scheme.

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The RSUs were granted to the following Grantees who are either a Director, chief executive and/or substantial shareholder (as defined in the Listing Rules) of the Company, or an associate (as defined in the Listing Rules) of any of them:

Name of the Grantee	Position in the Company	Number of RSUs Granted	Approximately of the issued share capital of the Company as at the date immediately prior to this announcement
Mr. Robin Meng	Executive Director	169,561	0.008%
Dr. Frank Zhang	Executive Director	113,041	0.005%
Dr. Li Zhu	Executive Director	113,041	0.005%
Ms. Sally Wang	Executive Director	113,041	0.005%
Ms. Sherry Shao	Rotating chief executive officer	841,470	0.038%

The grants of the RSUs to Mr. Robin Meng, Dr. Frank Zhang, Dr. Li Zhu, Ms. Sally Wang and Ms. Sherry Shao have been approved by the independent non-executive Directors and the Remuneration Committee in accordance with the 2021 RSU Scheme.

Save as disclosed above, to the best of the Directors' knowledge, information and belief having made all reasonable enquiries, as at the date of this announcement, none of the Grantees is: (i) a Director, or a chief executive, or a substantial shareholder (as defined in the Listing Rules) of the Company or an associate (as defined in the Listing Rules) of any of them; (ii) a participant with options and awards granted and to be granted exceeding the 1% individual limit under Rule 17.03D of the Listing Rules; or (iii) a related entity participant or service provider with options and awards granted and to be granted in any 12-month period exceeding 0.1% of the total number of issued Shares. The Grant is not subject to approval by the independent Shareholders.

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The Grants will be satisfied by issuance of new Shares within the Scheme Mandate Limit. The Stock Exchange had granted conditional listing approval for the new Shares underlying the share option(s) and/or award(s) within the Scheme Mandate Limit which may be granted pursuant to the 2021 RSU Scheme and all share schemes of the Company, subject to fulfillment of all other conditions of the respective share schemes of the Company. The issue of 14,736,658 new ordinary Shares to satisfy the Grant under the 2021 RSU Scheme will not be subject to the Shareholders' approval and such new Shares will be held on trust for the Grantees until the end of each vesting period and be transferred to the respective Grantees upon the end of each vesting period.

The new ordinary Shares to be issued and allotted by the Company under the Grant represent approximately 0.6734% of the total issued Shares of the Company as at the Date of Grant and approximately 0.6689% of the total issued Shares of the Company as enlarged by such issue and allotment.

NUMBER OF SHARES AVAILABLE FOR FUTURE GRANTS

As at the date of this announcement, after the Grant and taking into account the lapse of 223,305 share awards between 1 June 2026 and 4 June 2026 pursuant to the 2021 RSU Scheme, 188,226,028 underlying Shares will be available for future grants under the Scheme Mandate Limit, and 21,036,203 underlying Shares will be available for future grants under the Service Provider Sublimit.

DEFINITIONS

In this announcement, the following expressions have the following meanings unless the context requires otherwise:

"Board" the board of Directors;

"Circular" the circular of the Company dated 22 April 2024;

"Company" Genscript Biotech Corporation;

"Date of Grant" 4 June 2026;

"Director(s)" the director(s) of the Company;

"Director Grantees" Mr. Robin Meng, Dr. Frank Zhang, Dr. Li Zhu and Ms. Sally Wang, each of whom is an executive Directors of the Company;

"Dr. Frank Zhang" Dr. Fangliang Zhang, an executive Director of the Company;

"Employee Grantees" certain employees of the Group, who were granted 13,356,351 RSUs in total in accordance with the 2021 RSU Scheme on the Date of Grant;

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“Grant” the grant of 14,736,658 RSUs pursuant to the 2021 RSU Scheme to the Grantees on 4 June 2026;

“Grantees” the grantees who were granted RSUs pursuant to the 2021 RSU Scheme on 4 June 2026;

“Group” the Company and its subsidiaries;

“HK$” Hong Kong dollars, the lawful currency of Hong Kong;

“Listing Rules” the Rules Governing the Listing of Securities on the Stock Exchange as amended or supplemented from time to time;

“Mr. Robin Meng” Mr. Jiange Meng, the chairman and executive Director of the Company;

“Ms. Sally Wang” Ms. Ye Wang, an executive Director of the Company;

“Ms. Sherry Shao” Ms. Weihui Shao, the rotating chief executive officer of the Company;

“Remuneration Committee” the remuneration committee of the Board;

“RSU(s)” any restricted share unit representing the same number of Shares that may be offered by the Company to pursuant to the restricted share unit schemes adopted by the Company which may vest in the form of Shares issued or otherwise transferred by the Company and/or trust to a selected participant;

“Scheme Mandate Limit” the limit on grant(s) of share option(s) and/or award(s) over new Shares under all share schemes of the Company approved by the Shareholders, which must not exceed 212,768,651 (being 10% of the total number of issued Shares as at 21 June 2024, being the date of the Shareholders’ approval of the Scheme Mandate Limit);

“Service Provider Grantee” a service provider of the Group, who was granted 30,153 RSUs in total in accordance with the 2021 RSU Scheme on the Date of Grant;

“Service Provider Sublimit” a sublimit under the Scheme Mandate Limit for awards over new Shares under the restricted share unit scheme adopted by the Company granted to the Service Provider Grantee, which must not exceed 21,276,865 (being 1% of the total number of issued Shares as at 21 June 2024, being the date of the Shareholders’ approval of the Service Provider Sublimit);

“Share(s)” the ordinary shares in the share capital of the Company;

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"Shareholder(s)" holder(s) of the Shares;

"Stock Exchange" The Stock Exchange of Hong Kong Limited;

"2021 RSU Scheme" the restricted share unit scheme of the Company adopted on 23 August 2021 and subsequently amended on 26 May 2022, 21 June 2024 and 15 December 2025; and

% per cent.

By order of the Board
Genscript Biotech Corporation
Robin Meng
Chairman and Executive Director

Hong Kong, 4 June 2026

As at the date of this announcement, the executive Directors are Mr. Jiange Meng, Dr. Fangliang Zhang, Dr. Li Zhu and Ms. Ye Wang; and the independent non-executive Directors are Dr. Alphonse Galdes, Mr. Yiu Leung Andy Cheung ("Mr. Andy Cheung"), Mr. Jiuan Pan ("Mr. Ethan Pan"), Dr. John Quelch, Dr. Ross Grossman and Dr. Chenyang Shi ("Dr. Victor Shi").

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