Carson William H. 4

What Happened

• William H. Carson, a director of Annexon, purchased 8,000 shares of Annexon (ANNX) in an open-market transaction on May 11, 2026 at $5.78 per share, for a total cost of $46,240. This was a purchase (transaction code P), which investors often view as more informative than routine sales.

Key Details

• Transaction date and price: May 11, 2026 — 8,000 shares at $5.78 each (total $46,240).
• Transaction type/code: Open-market purchase (P).
• Shares owned after transaction: Not reported in the summary provided.
• Filing: Form 4 filed May 13, 2026 (two days after the reported trade), consistent with typical Form 4 timeliness.
• Footnote: Reported trade was effected under a Rule 10b5-1 trading plan adopted December 8, 2025 (see F1).

Context

• The purchase was made pursuant to a 10b5-1 plan, meaning the trade was prearranged under a pre-established plan; such trades can be less indicative of immediate insider views since timing and amounts may be automated.
• This was a straightforward open-market purchase (not an option exercise, award, or gift), so there are no derivative or tax-withholding complexities noted in the filing.