X0306 4 2023-03-03 0 0001704292 Zai Lab Ltd ZLAB 0001835824 Reinhart Harald C/O ZAI LAB LIMITED 314 MAIN STREET, 4TH FLOOR, SUITE 100 CAMBRIDGE MA 02142 0 1 0 0 See Remarks American Depositary Shares 2023-03-03 4 M 0 11480 3.00 A 30438 D American Depositary Shares 2023-03-03 4 S 0 11480 40.00 D 18958 D Stock Options (Right to Buy) 3.00 2023-03-03 4 M 0 11480 0.00 D 2027-05-12 American Depositary Shares 11480 0 D Each American Depositary Share (ADS) represents ten Ordinary Shares of the issuer. Our ADSs and Ordinary Shares are fully fungible. For purposes of this Form 4, we are reporting this in terms of ADSs. The reported transaction was effected pursuant to a sale plan adopted by the Reporting Person, dated 08/23/2022, that expires on 06/30/2023 and is intended to comply with Rule 10b5-1 under the Securities Exchange Act of 1934. The options vest in equal installments over four years beginning on 5/12/2018, the first anniversary of the date of grant. President and Head of Global Development for Neuroscience, Autoimmune and Infectious Diseases /s/ Bruce Blefeld, Attorney-in-Fact 2023-03-07