| Name | Relationship | Address | Signature | Signature date | CIK |
|---|---|---|---|---|---|
| Satter Muneer A | Director | C/O ANNEXON, INC., 1400 SIERRA POINT PKWY, BLDG C, STE 200, BRISBANE | /s/ Muneer A. Satter | 2025-11-21 | 0001315797 |
| Type | Sym | Class | Transaction | Value $ | Shares | Change % | * Price $ | Shares After | Date | Ownership | Footnotes |
|---|---|---|---|---|---|---|---|---|---|---|---|
| transaction | ANNX | Common Stock | Purchase | $1.79M | +400K | +4.49% | $4.48 | 9.31M | Nov 20, 2025 | See footnote | F1, F2, F3 |
| transaction | ANNX | Common Stock | Purchase | $1.81M | +423K | +4.54% | $4.28 | 9.73M | Nov 21, 2025 | See footnote | F1, F3, F4 |
| Id | Content |
|---|---|
| F1 | All shares were purchased by Alerce Medical Technology Partners, L.P. ("Alerce Medical"). The Reporting Person has sole voting and dispositive power over the shares held by Alerce Medical. The Reporting Person disclaims beneficial ownership of the shares except to the extent of his pecuniary interest therein. |
| F2 | This transaction was executed in multiple trades in prices ranging from $4.25 to $5.065, inclusive. The price reported in Column 4 above reflects the weighted average purchase price. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares purchased at each respective price within the range set forth in this footnote. |
| F3 | As of November 21, 2025, includes (a) 240,000 shares that are held by the Muneer A. Satter Revocable Trust for which the Reporting Person serves as trustee and, in such capacity, has sole voting and dispositive power over all such shares, (b) 567,240 shares that are held by various other trusts and entities for which the Reporting Person serves as trustee, investment advisor or manager, as applicable, and, in each such capacity, has sole voting and dispositive power over all such shares, (c) 1,147,738 shares that are held by Satter Medical Technology Partners, L.P. for which the Reporting Person has sole voting and dispositive power over all such shares and (d) 7,773,659 shares that are held by Alerce Medical for which the Reporting Person has sole voting and dispositive power over all such shares. The Reporting Person disclaims beneficial ownership of all shares included under (b), (c) and (d) of this footnote, except to the extent of his pecuniary interest therein. |
| F4 | This transaction was executed in multiple trades in prices ranging from $4.165 to $4.415, inclusive. The price reported in Column 4 above reflects the weighted average purchase price. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares purchased at each respective price within the range set forth in this footnote. |