SinoMab BioScience Limited — Share Issue/Capital Change 2025

Aug 29, 2025

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.

SINOMAB

SinoMab BioScience Limited

中國抗體製藥有限公司

(Incorporated in Hong Kong with limited liability)

(Stock code: 3681)

COMPLETION OF SUBSCRIPTIONS OF NEW SHARES UNDER GENERAL MANDATE

The Board is pleased to announce that the Completion of the Subscriptions between (i) the Company and Subscriber H and (ii) the Company and Subscriber O, in respect of an aggregate of 24,965,400 Subscriptions Shares took place on 29 August 2025 in accordance with the terms and conditions of each of the relevant Subscription Agreements.

INTRODUCTION

Reference is made to the announcements of SinoMab BioScience Limited (the "Company") dated 22 July 2025 and 15 August 2025 (collectively, the "Announcements") in relation to, among other things, the subscriptions of new shares of the Company under general mandate and the Completion of certain of the Subscriptions. Capitalised terms used in this announcement shall have the same meanings as defined in the Announcements unless otherwise stated. The terms of each of the Subscription Agreements are identical except for the name and details of the Subscribers.

COMPLETION OF SUBSCRIPTIONS OF NEW SHARES

The Board is pleased to announce that the Completion of the Subscriptions between (i) the Company and Subscriber H and (ii) the Company and Subscriber O, in respect of an aggregate of 24,965,400 Subscription Shares (the "Remaining Subscriptions") took place on 29 August 2025 in accordance with the terms and conditions of each of the relevant Subscription Agreements. An aggregate of 24,965,400 Shares, representing (i) approximately $1.83\%$ of the issued shares of the Company immediately before the Completion of the Remaining Subscriptions; and (ii) approximately $1.80\%$ of the issued shares of the Company as enlarged by the issue of the Subscription Shares of the Remaining Subscriptions, have been issued to the relevant Subscribers at the Subscription Price of HK$2.03 per Subscription Share. The net proceeds from the Remaining Subscriptions of approximately HK$50,679,762 will be applied in the manner as disclosed in the Announcements.

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EFFECT ON SHAREHOLDING STRUCTURE

The following table illustrates the shareholding structure of the Company (i) immediately before the Completion of the Remaining Subscriptions; and (ii) immediately after the Completion of the Remaining Subscriptions:

Name of Shareholders	Immediately before Completion of the Remaining Subscriptions		Immediately after Completion of the Remaining Subscriptions
	No. of Shares	Approximate %	No. of Shares	Approximate %
Hainan Haiyao Co., Ltd.
(海南海藥股份有限公司)¹	158,882,115	11.67	158,882,115	11.46
Skytech Technology Limited²	129,729,200	9.53	129,729,200	9.36
Apricot Entities³	113,330,670	8.32	113,330,670	8.17
Grogene Technology Limited
(格黎生物科技有限公司)⁴	9,998,800	0.73	9,998,800	0.72
Other Shareholders
Subscriber H⁵	634,363	0.05	2,900,263	0.21
Subscriber O⁶	35,300,400	2.59	57,999,900	4.18
Other Shareholders	913,797,388	67.11	913,797,388	65.90
Total	1,361,672,936	100.00	1,386,638,336	100.00

1. Pursuant to a share charge where Hainan Haiyao Co., Ltd (海南海藥股份有限公司) (“Hainan Haiyao”) charged 158,882,115 Shares to China Citic Bank Co., Ltd., Haikou Branch (“China Citic Bank”), China Citic Bank had a security interest in 158,882,115 Shares which were beneficially owned by Hainan Haiyao.
2. Skytech Technology Limited is a company wholly owned by Dr. Shui On LEUNG, an executive Director and the chairman of the Company.
3. Shares held by Apricot Capital (上海杏潭投資管理有限公司) and Shanghai Yueyi Investment Centre (Limited Partnership)* (上海月溢投資中心(有限合夥)) are through Apricot Oversea Holdings Limited and West Biolake Holdings Limited (collectively, the “Apricot Entities”), which are ultimately controlled by Dr. Wenyi LIU, a former non-executive Director. Dr. Wenyi LIU is the spouse of Mr. Jing QIANG.
4. Grogene Technology Limited (格黎生物科技有限公司) is a company wholly owned by Mr. Jing QIANG. Mr. Jing QIANG is the spouse of Dr. Wenyi LIU, a former non-executive Director.

5. Subscriber H became a Shareholder of the Company upon completion of the previous subscriptions as announced in the announcements of the Company dated 13 May 2025 and 29 May 2025.

6. 2 -

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1. One of the shareholders holding 65% of the issued shares of the managing partner of Subscriber O (being an exempted company with limited liability registered as a segregated portfolio company incorporated under the laws of the Cayman Islands), was also an individual subscriber in her individual capacity under the previous subscriptions as announced in the announcements of the Company dated 13 May 2025 and 29 May 2025. As at the date of this announcement, she is directly interested in 3,744,500 Shares.

By Order of the Board

SinoMab BioScience Limited

Dr. Shui On LEUNG

Executive Director, Chairman and Chief Executive Officer

Hong Kong SAR, 29 August 2025

As at the date of this announcement, the executive director of the Company is Dr. Shui On LEUNG, the non-executive directors of the Company are Dr. Haigang CHEN, Mr. Xun DONG, Ms. Xiaosu WANG and Dr. Jianmin ZHANG and the independent non-executive directors of the Company are Mr. George William Hunter CAUTHERLEY, Mr. Ping Cho Terence HON, Dr. Chi Ming LEE, Ms. Chi Sau Giselle LEE and Mr. Nan SHEN.

• For identification purpose only