X0508 4 2024-11-01 0001704292 Zai Lab Ltd ZLAB 0001985694 Chen Yajing C/O ZAI LAB LIMITED 314 MAIN STREET, 4TH FLOOR, SUITE 100 CAMBRIDGE MA 02142 true Chief Financial Officer false American Depositary Shares 2024-11-01 4 M 0 500 A 15661 D American Depositary Shares 2024-11-04 4 S 0 167 30.662 D 15494 D Restricted Share Units 2024-11-01 4 M 0 500 0 D American Depositary Shares 500 500 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. ADSs acquired upon vesting of Restricted Share Units ("RSUs"). Each RSU represents a contingent right to receive one ADS. These ADSs were sold automatically to cover taxes upon vesting of RSUs. The Restricted Share Units vest in equal annual installments over four years beginning on 11/01/2022, the first anniversary of the date of grant. Vested shares will be delivered to the reporting person following vesting. /s/ Bruce Blefeld, Attorney-in-Fact 2024-11-05