X0306 4 2020-06-12 0 0001783183 Phathom Pharmaceuticals, Inc. PHAT 0001720320 Frazier Life Sciences IX, L.P. C/O FRAZIER HEALTHCARE PARTNERS 601 UNION STREET, SUITE 3200 SEATTLE WA 98101 0 0 1 0 0001782789 FHMLS IX, L.P. C/O FRAZIER HEALTHCARE PARTNERS 601 UNION STREET, SUITE 3200 SEATTLE WA 98101 0 0 1 0 0001782791 FHMLS IX, L.L.C. C/O FRAZIER HEALTHCARE PARTNERS 601 UNION STREET, SUITE 3200 SEATTLE WA 98101 0 0 1 0 0001341382 Topper James N C/O FRAZIER HEALTHCARE PARTNERS 601 UNION STREET, SUITE 3200 SEATTLE WA 98101 1 0 1 0 0001365617 Heron Patrick J C/O FRAZIER HEALTHCARE PARTNERS 601 UNION STREET, SUITE 3200 SEATTLE WA 98101 0 0 1 0 Common Stock 2020-06-12 4 J 0 1456854 0.00 D 5827415 D Common Stock 1 I See footnote Common Stock 12596 I See footnote Common Stock 3912 I See footnote Common Stock 14937 I See footnote Represents a pro rata distribution in-kind by Frazier Life Sciences IX, L.P. ("FLS IX") to its limited partners for no consideration. Represents shares held of record by FLS IX. The general partner of FLS IX is FHMLS IX, L.P., and the general partner of FHMLS IX, L.P. is FHMLS IX, L.L.C. James Topper and Patrick Heron are the sole managing members of FHMLS IX, L.L.C. and share voting and investment power of the securities held by FLS IX. Dr. Topper and Mr. Heron disclaim beneficial ownership of such securities except to the extent of their pecuniary interest therein. Reflects shares of Common Stock received in the distribution in-kind described herein. Represents shares held of record by FHMLS IX, L.L.C. James Topper and Patrick Heron are the sole managing members of FHMLS IX, L.L.C. and share voting and investment power of the securities held by FLS IX. Dr. Topper and Mr. Heron disclaim beneficial ownership of such securities except to the extent of their pecuniary interest therein. These shares were previously held through FLS IX. Represents shares held directly by Dr. Topper. These shares were previously held through FLS IX. Represents shares held of record by Topper Group III LLC. Dr. Topper is a manager of Topper Group III LLC and has voting and investment power of the securities held by Topper Group III LLC. These shares were previously held through FLS IX. Represents shares held by The Heron Living Trust 11/30/2004. Mr. Heron is the co-trustee of The Heron Living Trust 11/30/2004 and has voting and investment power of the securities held by The Heron Living Trust 11/30/2004. These shares were previously held through FLS IX. Frazier Life Sciences IX, L.P., By: FHMLS IX, L.P., its general partner, By: FHMLS IX, L.L.C., its general, partner, By: /s/ Steve R. Bailey, Chief Financial Officer 2020-06-16 FHMLS IX, L.P., By: FHMLS IX, L.L.C., its general partner, By: /s/ Steve R. Bailey, Chief Financial Officer 2020-06-16 FHMLS IX, L.L.C., By: /s/ Steve R. Bailey, Chief Financial Officer 2020-06-16 /s/ Steve R. Bailey, Attorney-in-Fact for James Topper 2020-06-16 /s/ Steve R. Bailey, Attorney-in-Fact for Patrick Heron 2020-06-16