X0206 3 2020-07-23 0 0001528115 Annexon, Inc. ANNX 0001237289 SANDELL SCOTT D 1954 GREENSPRING DRIVE SUITE 600 TIMONIUM MD 21093 0 0 1 0 Series B Preferred Stock Common Stock 1591599 I See Note 2 Series C Preferred Stock Common Stock 672636 I See Note 2 Series D Preferred Stock Common Stock 231452 I See Note 2 The shares of Series B Preferred Stock will automatically convert on a 1-for-8.81 basis into Common Stock immediately prior to the closing of the Issuer's initial public offering. The shares have no expiration date. The Reporting Person is a manager of NEA 15 GP, LLC, which is the sole general partner of NEA Partners 15, L.P. ("NEA Partners 15"). NEA Partners 15 is the sole general partner of New Enterprise Associates 15, L.P. ("NEA 15"), which is the direct beneficial owner of the shares. The Reporting Person disclaims beneficial ownership within the meaning of Section 16 of the Securities Exchange Act of 1934, as amended, or otherwise of such portion of the shares held by NEA 15 in which the Reporting Person has no pecuniary interest. The shares of Series C Preferred Stock will automatically convert on a 1-for-8.81 basis into Common Stock immediately prior to the closing of the Issuer's initial public offering. The shares have no expiration date. The shares of Series D Preferred Stock will automatically convert on a 1-for-8.81 basis into Common Stock immediately prior to the closing of the Issuer's initial public offering. The shares have no expiration date. /s/ Sasha Keough, attorney-in-fact 2020-07-23