Zai Lab Limited — Capital/Financing Update 2020

Sep 25, 2020

Unless otherwise defined herein, capitalized terms used herein shall have the same meanings as those defined in the Hong Kong prospectus dated September 17, 2020 (the “ Prospectus ”) issued by Zai Lab Limited (the “ Company ”).

Hong Kong Exchanges and Clearing Limited, The Stock Exchange of Hong Kong Limited (the “ Stock Exchange ”) and Hong Kong Securities Clearing Company Limited (“ HKSCC ”) 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.

This announcement is for information purposes only and does not constitute an invitation or offer to acquire, purchase or subscribe for any securities. This announcement is not a prospectus. Potential investors should read the Prospectus for detailed information about the Global Offering described below before deciding whether or not to invest in the Shares thereby being offered.

This announcement is not for release, publication, distribution, directly or indirectly, in or into the United States (including its territories and possessions, any state of the United States and the District of Columbia). This announcement does not constitute or form a part of any offer or solicitation to purchase or subscribe for securities in the United States. Securities may not be offered or sold in the United States absent registration or an exemption from registration under the U.S. Securities Act of 1933 as amended from time to time (the “ U.S. Securities Act ”). Any public offering of our securities to be made in the United States will be made by means of a prospectus that may be obtained from us and that will contain detailed information about us and our management, as well as financial statements. We have filed a shelf registration statement on Form F-3ASR and a final prospectus supplement with the United States Securities and Exchange Commission in connection with the Global Offering.

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**Zai Lab Limited 再鼎醫藥有限公司 ***

(Incorporated in the Cayman Islands with limited liability)

(Stock Code: 9688)

CLARIFICATION ANNOUNCEMENT

The Board wishes to supplement and/or revise certain inadvertent typographical errors in the announcement of offer price and allotment results issued by the Company dated September 25, 2020 (the “ Allotment Results Announcement ”).

Reference is made to the last paragraph of page 1 of the Allotment Results Announcement. The Company would like to clarify that the reference to “Monday, November 28, 2020” should be “Monday, September 28, 2020” instead.

Reference is made to the Chinese name of the Company that appears on page 2 of the Allotment Results Announcement. The Company would like to clarify that such Chinese name of the Company is for identification only.

Reference is made to the subsection headed “Results of Allocations” on pages 5 and 14 of the Allotment Results Announcement. The Company would like to clarify that the references of the allocation results telephone enquiry of “+852 2862 8669” should be “+852 2862 8555” instead, which should be made available “between 9:00 a.m. and 6:00 p.m. on Friday, September 25, 2020, and from Monday, September 28, 2020 to Wednesday, September 30, 2020”.

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Save for the above, all other information stated in the Allotment Results Announcement remain unchanged.

By order of the Board Zai Lab Limited Samantha Du Director, Chairwoman and Chief Executive Officer

Hong Kong September 25, 2020

As at the date of this announcement, the board of directors of the Company comprises Dr. Samantha Du and Mr. Tao Fu as the directors, and Dr. Kai-Xian Chen, Dr. John Diekman, Ms. Nisa Leung, Mr. William Lis, Mr. Leon O. Moulder, Jr. and Mr. Peter Wirth as the independent directors.

• For identification only

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