X0306 4 2020-07-21 1 0001807901 Pandion Therapeutics, Inc. PAND 0001465837 Boxer Capital, LLC 11682 EL CAMINO REAL, SUITE 320 SAN DIEGO CA 92130 0 0 1 0 0001465836 Boxer Asset Management Inc. CAY HOUSE, EP TAYLOR DRIVE N7776 LYFORD CAY NEW PROVIDENCE C5 BAHAMAS 0 0 1 0 0001642355 Braslyn Ltd. CAY HOUSE, EP TAYLOR DRIVE N7776 LYFORD CAY NEW PROVIDENCE C5 BAHAMAS 0 0 1 0 0001015747 LEWIS JOSEPH CAY HOUSE, EP TAYLOR DRIVE N7776 LYFORD CAY NEW PROVIDENCE C5 BAHAMAS 0 0 1 0 0001465914 Davis Aaron I. 11682 EL CAMINO REAL, SUITE 320 SAN DIEGO CA 92130 0 0 1 0 0001468223 MVA Investors, LLC 11682 EL CAMINO REAL, SUITE 320 SAN DIEGO CA 92130 0 0 1 0 Common Stock 2020-07-21 4 C 0 1385291 A 1385291 D Common Stock 2020-07-21 4 C 0 23622 A 23622 I See footnote Common Stock 2020-07-21 4 P 0 722222 18.00 A 2107513 D Series B Preferred Stock 2020-07-21 4 C 0 7064136 0.00 D Common Stock 1385291 0 D Series B Preferred Stock 2020-07-21 4 C 0 120460 0.00 D Common Stock 23622 0 I See footnote The Series B Preferred Stock converted into Common Stock on a 5.0994-for-one basis upon the closing of the Issuer's initial public offering without payment of consideration. The Series B Preferred Stock was convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The shares had no expiration date. These securities are owned directly by Boxer Capital, LLC ("Boxer Capital"), which may be deemed to be a member of a "group" for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended, consisting of (i) Boxer Capital, (ii) Boxer Asset Management Inc. ("Boxer Management"), (iii) Braslyn Ltd. ("Braslyn"), (iv) Joseph C. Lewis, (v) MVA Investors, LLC ("MVA Investors") and (vi) Aaron I. Davis (collectively, the "Boxer Group"), and indirectly by Boxer Management and Joseph C. Lewis by virtue of their ownership in Boxer Capital. Each member of the Boxer Group other than Boxer Capital disclaims beneficial ownership of these securities to the extent it or he does not have a pecuniary interest therein. These securities are owned directly and solely by MVA Investors, which has sole voting and dispositive power with respect to these securities. Each member of the Boxer Group other than MVA Investors disclaims beneficial ownership of these securities to the extent it or he does not have a pecuniary interest therein. Boxer Capital, LLC, By: /s/ Aaron I. Davis, Chief Executive Officer 2020-07-21 Boxer Asset Management Inc., By: /s/ Jason C. Callender, Director 2020-07-21 Braslyn Ltd., By: /s/ Joseph C. Lewis, Director 2020-07-21 /s/ Joseph C. Lewis 2020-07-21 /s/ Aaron I. Davis 2020-07-21 MVA Investors, LLC, By: /s/ Aaron I. Davis, Chief Executive Officer 2020-07-21