X0306 4 2020-07-10 0 0001785173 89bio, Inc. ETNB 0001713663 Longitude Capital Partners III, LLC 2740 SAND HILL RD 2ND FLOOR MENLO PARK CA 94025 0 0 1 0 0001674099 Longitude Venture Partners III, L.P. 2740 SAND HILL RD 2ND FLOOR MENLO PARK CA 94025 0 0 1 0 0001431159 Tammenoms Bakker Juliet 2740 SAND HILL RD 2ND FLOOR MENLO PARK CA 94025 0 0 1 0 0001253886 ENRIGHT PATRICK G 2740 SAND HILL RD 2ND FLOOR MENLO PARK CA 94025 0 0 1 0 Common Stock 2020-07-10 4 P 0 109090 27.50 A 2600877 I See footnote On July 10, 2020, Longitude Venture Partners III, L.P. ("Longitude Venture III") purchased 109,090 shares of the Issuer's common stock at a price of $27.50 per share in the Issuer's follow-on public offering. These shares are held directly by Longitude Venture III. Longitude Capital Partners III, LLC ("Longitude Capital III") is the general partner of Longitude Venture III and may be deemed to have voting, investment and dispositive power with respect to these securities. Patrick G. Enright and Juliet Tammenoms Bakker are the managing members of Longitude Capital III (each a "Manager" and collectively, the "Managers") and may each be deemed to share voting, investment and dispositive power with respect to these securities. Each of Longitude Capital III and the Managers disclaims beneficial ownership of these securities and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interests therein. Longitude Venture Partners III, L.P.; By /s/ Patrick G. Enright, Managing Member 2020-07-14 Longitude Capital Partners III, LLC; By /s/ Patrick G. Enright, Managing Member 2020-07-14 /s/ Juliet Tammenoms Bakker 2020-07-14 /s/ Patrick G. Enright 2020-07-14