Annexon, Inc. — Director's Dealing 2020

Jul 23, 2020

SEC Form 3 — Initial Statement of Beneficial Ownership

Issuer: Annexon, Inc. (ANNX)
CIK: 0001528115
Period of Report: 2020-07-23

Reporting Person: Bain Capital Life Sciences Investors, LLC (10% Owner)
Reporting Person: Bain Capital Life Sciences Partners, LP (10% Owner)
Reporting Person: Bain Capital Life Sciences Fund, L.P. (10% Owner)
Reporting Person: BCIP Life Sciences Associates, LP (10% Owner)
Reporting Person: Koppel Adam (10% Owner)
Reporting Person: Schwartz Jeffrey Lawrence (10% Owner)

Holdings (Derivative)

Security	Exercise Price	Expiration	Underlying	Shares	Ownership
Series C Preferred Stock	$		Common Stock (22222221)		Indirect
Series D Preferred Stock	$		Common Stock (2812543)		Indirect

Footnotes

F1: 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.

F2: 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.

F3: Represents 20,158,775 shares of Series C Preferred Stock held of record by Bain Capital Life Sciences Fund, L.P. ("BCLS") and 2,063,446 shares of Series C Preferred Stock held of record by BCIP Life Sciences Associates, LP ("BCIPLS" and, together with BCLS, the "Bain Capital Life Sciences Entities").

F4: Represents 2,551,384 shares of Series D Preferred Stock held of record by BCLS and 261,159 shares of Series D Preferred Stock held of record by BCIPLS.

F5: Bain Capital Life Sciences Partners, LP ("BCLSP") is the general partner of BCLS. As a result, BCLSP may be deemed to share voting and dispositive power with respect to the securities held by BCLS. BCLSP disclaims beneficial ownership of such securities except to the extent of their pecuniary interest therein.

F6: Bain Capital Life Sciences Investors, LLC ("BCLSI"), whose managers are Jeffrey Schwartz and Adam Koppel, is the general partner of BCLSP and governs the investment strategy and decision-making process with respect to investments held by BCIPLS, whose general partner is Boylston Coinvestors, LLC. As a result, each of BCLSI, Mr. Schwartz and Dr. Koppel may be deemed to share voting and dispositive power over the shares held by the Bain Capital Life Sciences Entities. BCLSI, Mr. Schwartz and Dr. Koppel each disclaim beneficial ownership of such securities except to the extent of their pecuniary interest therein.