RA Capital Management Reports New 5.2% Passive Stake in Zai Lab Limited

On April 6, 2026, RA Capital Management, L.P., along with Peter Kolchinsky, Rajeev Shah, and RA Capital Healthcare Fund, L.P., filed a Schedule 13G disclosing a new passive ownership stake in Zai Lab Limited (ZLAB). The reporting persons collectively hold 5,743,533 American Depositary Shares (ADSs), which represent 57,435,330 ordinary shares of the issuer. This position accounts for approximately 5.2% of the company's outstanding ordinary shares, based on the 1,106,407,390 shares outstanding as of February 20, 2026. RA Capital Management serves as the investment adviser for the Fund, with Dr. Kolchinsky and Mr. Shah acting as controlling persons. While the Fund directly holds the securities, it has delegated voting and dispositive power to RA Capital. The filing includes a standard certification that the shares were acquired in the ordinary course of business and not for the purpose of influencing or changing the control of the issuer. This filing marks an increase from a previously reported 0% ownership level.