Zai Lab Limited — Capital/Financing Update 2020

Sep 17, 2020

Hong Kong Exchanges and Clearing Limited, The Stock Exchange of Hong Kong Limited (the “ Hong Kong 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 Hong Kong prospectus dated September 17, 2020 (the “ Prospectus ”) issued by Zai Lab Limited (the “ Company ”) 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 are conducting a public offering of the securities described herein in the United States pursuant to our shelf registration statement on Form F-3ASR filed with the United States Securities and Exchange Commission on March 29, 2020.

Unless otherwise defined in this announcement, capitalized terms used herein shall have the same meanings as those defined in the Prospectus.

In connection with the Global Offering, Goldman Sachs (Asia) L.L.C. as stabilization manager (the “ Stabilization Manager ”), its affiliates or any person acting for it, on behalf of the Underwriters, may effect transactions with a view to stabilizing or supporting the market price of the Shares at a level higher than that which might otherwise prevail for a limited period on and after the Listing Date. However, there is no obligation on the Stabilization Manager, its affiliates or any person acting for it, to conduct any such stabilizing action, which, if commenced, will be done at the sole and absolute discretion of the Stabilization Manager, its affiliates or any person acting for it, and may be discontinued at any time. Any such stabilizing activity is required to be brought to an end on the 30th day after the last day for the lodging of applications under the Hong Kong Public Offering. Such stabilizing action, if taken, may be effected in all jurisdictions where it is permissible to do so, in each case in compliance with all applicable laws, rules and regulatory requirements, including the Securities and Futures (Price Stabilizing) Rules (Cap. 571W of the Laws of Hong Kong), as amended, made under the Securities and Futures Ordinance (Cap. 571 of the Laws of Hong Kong).

Potential investors should be aware that stabilizing action cannot be taken to support the price of the Shares for longer than the stabilization period which begins on the Listing Date and is expected to expire on October 22, 2020, being the 30th day after the last day for the lodging of applications under the Hong Kong Public Offering. After this date, no further stabilizing action may be taken, demand for the Shares, and therefore the price of the Shares, could fall.

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Zai Lab Limited 再鼎醫藥有限公司[*] (Incorporated in the Cayman Islands with limited liability)

GLOBAL OFFERING

Number of Offer Shares under : 10,564,050 Shares (subject to the Overthe Global Offering allotment Option) Number of Hong Kong Offer Shares : 771,700 Shares (subject to adjustment) Number of International Offer Shares :

• : 771,700 Shares (subject to adjustment) : 9,792,350 Shares (subject to adjustment and the Over-allotment Option)

• Maximum Offer Price : HK$648.00, plus brokerage of 1%, SFC transaction levy of 0.0027% and Stock Exchange trading fee of 0.005% (payable in full on application in Hong Kong dollars and subject to refund)

Nominal value : US$0.00006 per Share Stock Code : 9688

Joint Sponsors, Joint Global Coordinators, Joint Bookrunners and Joint Lead Managers

Joint Global Coordinator, Joint Bookrunner and Joint Lead Manager

Joint Bookrunners and Joint Lead Managers

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IMPORTANT NOTICE TO INVESTORS:

1. FULLY ELECTRONIC APPLICATION PROCESS

We have adopted a fully electronic application process for the Hong Kong Public Offering. We will not provide printed copies of the Prospectus or printed copies of any application forms to the public in relation to the Hong Kong Public Offering.

The Prospectus is available at the website of the Hong Kong Stock Exchange at www.hkexnews.hk under the “HKEXnews > New Listings > New Listing Information” section, and our website at http://www.zailaboratory.com. If you require a printed copy of the Prospectus, you may download and print from the website addresses above.

To apply for the Hong Kong Offer Shares, you may:

• (1) apply online through the White Form eIPO service at www.eipo.com.hk ; or

• (2) apply through the CCASS EIPO service to electronically cause HKSCC Nominees to apply on your behalf, including by:

• (i) instructing your broker or custodian who is a CCASS Clearing Participant or a CCASS Custodian Participant to give electronic application instructions via CCASS terminals to apply for the Hong Kong Offer Shares on your behalf; or

• (ii) (if you are an existing CCASS Investor Participant ) giving electronic application instructions through the CCASS Internet System ( https://ip.ccass.com ) or through the CCASS Phone System by calling +852 2979 7888 (using the procedures in HKSCC’s “An Operating Guide for Investor Participants” in effect from time to time). HKSCC can also input electronic application instructions for CCASS Investor Participants through HKSCC’s Customer Service Centre at 1/F, One & Two Exchange Square, 8 Connaught Place, Central, Hong Kong by completing an input request.

If you have any question about the application for the Hong Kong Offer Shares, you may call the enquiry hotline of our Hong Kong Share Registrar and White Form eIPO Service Provider, Computershare Hong Kong Investor Services Limited, both at +852 2862 8648 on the following dates:

Thursday, September	17,	2020	–	9:00	a.m. to	9:00 p.m.
Friday, September	18,	2020	–	9:00	a.m. to	9:00 p.m.
Saturday, September	19,	2020	–	9:00	a.m. to	6:00 p.m.
Sunday, September	20,	2020	–	9:00	a.m. to	6:00 p.m.
Monday, September	21,	2020	–	9:00	a.m. to	9:00 p.m.
Tuesday, September	22,	2020	–	9:00	a.m. to	12:00 noon

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We will not provide any physical channels to accept any application for the Hong Kong Offer Shares by the public. The contents of the electronic version of the Prospectus are identical to the printed Prospectus as registered with the Registrar of Companies in Hong Kong pursuant to Section 342C of the Companies (WUMP) Ordinance.

If you are an intermediary , broker or agent , please remind your customers, clients or principals, as applicable, that the Prospectus is available online at the website addresses above.

Please refer to the section headed “How to Apply for Hong Kong Offer Shares” in the Prospectus for further details of the procedures through which you can apply for the Hong Kong Offer Shares electronically.

Your application must be for a minimum of 50 Hong Kong Offer Shares and in one of the numbers set out in the table below. You are required to pay the amount next to the number you select.

No. of Hong Kong Offer Shares applied for 50 100 150 200 250 300 350 400 450 500 600 700 800 900	Amount payable on application HK$ 32,726.49 65,452.99 98,179.48 130,905.98 163,632.47 196,358.97 229,085.46 261,811.96 294,538.45 327,264.95 392,717.94 458,170.93 523,623.92 589,076.91	No. of Hong Kong Offer Shares applied for 1,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000 5,500 6,000 6,500 7,000 7,500	Amount payable on application HK$ 654,529.90 981,794.84 1,309,059.79 1,636,324.74 1,963,589.69 2,290,854.64 2,618,119.58 2,945,384.53 3,272,649.48 3,599,914.43 3,927,179.38 4,254,444.32 4,581,709.27 4,908,974.22	No. of Hong Kong Offer Shares applied for 8,000 8,500 9,000 9,500 10,000 20,000 30,000 40,000 50,000 60,000 70,000 80,000 90,000 100,000	Amount payable on application HK$ 5,236,239.17 5,563,504.12 5,890,769.06 6,218,034.01 6,545,298.96 13,090,597.92 19,635,896.88 26,181,195.84 32,726,494.80 39,271,793.76 45,817,092.72 52,362,391.68 58,907,690.64 65,452,989.60	No. of Hong Kong Offer Shares applied for 200,000 300,000 385,850(1)	Amount payable on application HK$
							130,905,979.20 196,358,968.80 252,550,360.37

(1) Maximum number of Hong Kong Offer Shares you may apply for.

No application for any other number of the Hong Kong Offer Shares will be considered and any such application is liable to be rejected.

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THE LISTING APPLICATION

We have applied to the Hong Kong Stock Exchange for the listing of, and permission to deal in, the Shares in issue, the Shares to be issued pursuant to the Global Offering (including the additional Shares that may be issued pursuant to the exercise of the Over-allotment Option) and the Shares to be issued pursuant to the Equity Plans, including pursuant to the exercise of options or other awards that have been or may be granted from time to time.

STRUCTURE OF THE GLOBAL OFFERING

The Global Offering comprises:

• the Hong Kong Public Offering of initially 771,700 Shares (subject to reallocation) representing approximately 7.3% of the total number of Offer Shares initially available under the Global Offering, and

• the International Offering of initially 9,792,350 Shares (subject to reallocation and the Over-allotment Option) representing approximately 92.7% of the total number of Offer Shares initially available under the Global Offering.

The allocation of the Offer Shares between the Hong Kong Public Offering and the International Offering will be subject to reallocation as described in the section headed “Structure of the Global Offering” in the Prospectus.

In particular, the Joint Representatives may, at their sole discretion, pursuant to an alternative clawback mechanism applied for by us to the Hong Kong Stock Exchange, reallocate Offer Shares from the International Offering to the Hong Kong Public Offering to satisfy valid applications under the Hong Kong Public Offering. In accordance with Guidance Letter HKEX-GL91-18 issued by the Hong Kong Stock Exchange, if such reallocation is done other than pursuant to the alternative clawback mechanism as described in the section headed “Structure of the Global Offering – the Hong Kong Public Offering – Reallocation” in the Prospectus, the maximum total number of Offer Shares that may be reallocated to the Hong Kong Public Offering following such reallocation shall be not more than double the initial allocation to the Hong Kong Public Offering (i.e. 1,543,400 Shares, representing approximately 14.6% of the total number of Offer Shares initially available under the Global Offering).

Under the International Underwriting Agreement, we expect to grant to the International Underwriters, exercisable by the Joint Representatives (for themselves and on behalf of the International Underwriters), the Over-allotment Option, exercisable within 30 days after the last day for lodging applications under the Hong Kong Public Offering (the last day for exercise of the Over-allotment Option being October 22, 2020) to require us to issue up to an aggregate of 1,584,600 Shares, representing not more than 15% of the total number of Offer Shares initially available under the Global Offering, at the International Offer Price, to cover over-allocations in the International Offering, if any. In the event the Over-allotment Option is exercised, we will make an announcement which will be posted on the website of the Hong Kong Stock Exchange ( www.hkexnews.hk ) and on our website ( http://www.zailaboratory.com ), respectively.

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PRICING

The Public Offer Price will not be more than HK$648.00 per Hong Kong Offer Share. Applicants for the Hong Kong Offer Shares are required to pay, on application, the maximum Public Offer Price of HK$648.00 per Offer Share in addition to the brokerage of 1%, SFC transaction levy of 0.0027% and the Hong Kong Stock Exchange trading fee of 0.005%, subject to refund if the Public Offer Price as finally determined is less than HK$648.00 per Offer Share.

EXPECTED TIMETABLE

Hong Kong Public Offering commences . . . . . . . . . . . . 9:00 a.m. on Thursday, September 17, 2020

Latest time for completing electronic applications under White Form eIPO service through the designated website www.eipo.com.hk . . . . . . . . . . . . . . . . . . . .11:30 a.m. on Tuesday, September 22, 2020

Application lists open . . . . . . . . . . . . . . . . . . . . . . . . . .11:45 a.m. on Tuesday, September 22, 2020

Latest time for (a) completing payment for White Form eIPO applications by effecting internet banking transfer(s) or PPS payment transfer(s) and (b) giving electronic application instructions to HKSCC . . . . . . . . . . . . 12:00 noon on Tuesday, September 22, 2020

Application lists close. . . . . . . . . . . . . . . . . . . . . . . . . 12:00 noon on Tuesday, September 22, 2020

Expected Price Determination Date. . . . . . . . . . . . . . . . . . . . . . . . . . . Tuesday, September 22, 2020

Announcement of the Public Offer Price and

the International Offer Price on our website at http://www.zailaboratory.com and the website of the Hong Kong Stock Exchange at www.hkexnews.hk on or around. . . . . . . . . . . . . . . . . . . . . . . . . . . . Friday, September 25, 2020

Announcement of the level of indications of

interest in the International Offering, the level of applications in the Hong Kong Public Offering and the basis of allocation of the Hong Kong Offer Shares on our website at http://www.zailaboratory.com and the website of the Hong Kong Stock Exchange at www.hkexnews.hk on or before . . . . . . . . . . . . . . . . . . . . . . . . . . . . Friday, September 25, 2020

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The results of allocations in the Hong Kong Public Offering (with successful applicants’ identification document numbers, where appropriate) to be available through a variety of channels, including:

• in the announcement to be posted on our website and the website of the Hong Kong Stock Exchange at www.zailaboratory.com and www.hkexnews.hk ,

• respectively . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Friday, September 25, 2020

• from the designated results of allocations website at www.iporesults.com.hk (alternatively: English https://www.eipo.com.hk/en/Allotment ; Chinese https://www.eipo.com.hk/zh-hk/Allotment) with

• a “search by ID” function from . . . . . . . . . . . . . . . . . . . . . . Friday, September 25, 2020 to Thursday, October 1, 2020

• from the allocation results telephone enquiry by calling +852 2862 8555 between

• 9:00 a.m. and 6:00 p.m. from . . . . . . . . . . . . . . . . . . . . . . Friday, September 25, 2020 and

  • from Monday, September 28, 2020

  • to Wednesday, September 30, 2020

Share certificates in respect of wholly or partially successful applications to be dispatched or deposited into CCASS on or before. . . . . . . . . . . . . . . . . . . . . . . . . . Friday, September 25, 2020

• White Form e-Refund payment instructions/refund checks in respect of wholly or partially successful applications (if applicable) or wholly or partially unsuccessful applications to be dispatched on or around . . . . . . . . . . Friday, September 25, 2020

Dealings in the Shares on the Hong Kong Stock

Exchange expected to commence at 9:00 a.m. on . . . . . . . . . . . . . . Monday, September 28, 2020

SETTLEMENT

Subject to the granting of the approval for listing of, and permission to deal in, the Shares on the Hong Kong Stock Exchange and compliance with the stock admission requirements of HKSCC, the Shares will be accepted as eligible securities by HKSCC for deposit, clearance and settlement in CCASS with effect from the date of commencement of dealings in the Shares on the Hong Kong Stock Exchange or such other date as may be determined by HKSCC. Settlement of transactions between participants of the Hong Kong Stock Exchange is required to take place in CCASS on the second business day after any trading day. All activities under CCASS are subject to the General Rules of CCASS and CCASS Operational Procedures in effect from time to time. All necessary arrangements have been made to enable the Shares to be admitted into CCASS.

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ELECTRONIC APPLICATION CHANNELS

White Form eIPO

You may submit your application through the White Form eIPO service through the designated website at www.eipo.com.hk (24 hours daily, except on the last day for applications) from 9:00 a.m. on Thursday, September 17, 2020 until 11:30 a.m. on Tuesday, September 22, 2020 and the latest time for completing full payment of application monies in respect of such applications will be 12:00 noon on Tuesday, September 22, 2020, the last day for applications, or such later date as described in the section headed “How to Apply for Hong Kong Offer Shares – Effect of Bad Weather and Extreme Conditions on the Opening and Closing of the Application Lists” in the Prospectus.

CCASS EIPO

CCASS Clearing/Custodian Participants can input electronic application instructions at the following times on the following dates:

– Thursday, September 17, 2020 9:00 a.m. to 8:30 p.m. – Friday, September 18, 2020 8:00 a.m. to 8:30 p.m. – Saturday, September 19, 2020 8:00 a.m. to 1:00 p.m. – Monday, September 21, 2020 8:00 a.m. to 8:30 p.m. Tuesday, September 22, 2020 – 8:00 a.m. to 12:00 noon

The times in this sub-section are subject to change as HKSCC may determine from time to time with prior notification to CCASS Clearing/Custodian Participants and/or CCASS Investor Participants.

CCASS Investor Participants can input electronic application instructions from 9:00 a.m. on Thursday, September 17, 2020 until 12:00 noon on Tuesday, September 22, 2020 (24 hours daily, except on Tuesday, September 22, 2020 the last day for applications).

The latest time for inputting your electronic application instructions will be 12:00 noon on Tuesday, September 22, 2020, the last day for applications, or such later time as described in the section headed “How to Apply for Hong Kong Offer Shares – Effect of Bad Weather and Extreme Conditions on the Opening and Closing of the Application Lists” in the Prospectus.

If you are instructing your broker or custodian who is a CCASS Clearing Participant or a CCASS Custodian Participant to give electronic application instructions via CCASS terminals to apply for the Hong Kong Offer Shares on your behalf, you are advised to contact your broker or custodian for the latest time for giving such instructions which may be different from the latest time as stated above.

The application monies (including the brokerage, SFC transaction levy and the Hong Kong Stock Exchange trading fee) will be held by the receiving bank and on behalf of the Company after the closing of the application lists and the refund monies, if any, will be returned to the applicants without interest on or before Friday, September 25, 2020.

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Please refer to the sections headed “Structure of the Global Offering” and “How to Apply for Hong Kong Offer Shares” of the Prospectus for details of the conditions and procedures of the Hong Kong Public Offering.

PUBLICATION OF RESULTS

We expect to announce the level of indications of interest in the International Offering, the level of applications in the Hong Kong Public Offering and the basis of allocation of the Hong Kong Offer Shares on Friday, September 25, 2020 on our website at http://www.zailaboratory.com and the website of the Hong Kong Stock Exchange at www.hkexnews.hk .

The results of allocations and the Hong Kong identity card/passport/Hong Kong business registration numbers of successful applicants (where applicable) under the Hong Kong Public Offering will be available through a variety of channels at the times and date and in the manner specified in the section headed “How to Apply for Hong Kong Offer Shares – Publication of Results” in the Prospectus.

If an application is rejected, not accepted or accepted in part only, or if the Public Offer Price as finally determined is less than the maximum Public Offer Price of HK$648.00 per Offer Share (excluding brokerage, SFC transaction levy and the Hong Kong Stock Exchange trading fee thereon), or if the conditions of the Hong Kong Public Offering are not fulfilled in accordance with “Structure of the Global Offering – Conditions of the Global Offering” in the Prospectus or if any application is revoked, the application monies, or the appropriate portion thereof, together with the related brokerage, SFC transaction levy and the Hong Kong Stock Exchange trading fee, will be refunded, without interest.

No temporary documents of title will be issued in respect of the Shares and no receipt will be issued for sums paid on application. Share certificates will only become valid at 8:00 a.m. on Monday, September 28, 2020, provided that the Global Offering has become unconditional and the right of termination described in the “Underwriting – Underwriting Arrangements and Expenses – Hong Kong Public Offering – Grounds for Termination” section in the Prospectus has not been exercised.

Dealings in the Shares are expected to commence at 9:00 a.m. on Monday, September 28, 2020. The Shares will be traded in board lots of 50 Shares each. The stock code of the Shares is 9688.

By order of the Board Zai Lab Limited Samantha Du

Director, Chairwoman and Chief Executive Officer

Hong Kong, September 17, 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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