Posner Brian S 4

What Happened

• Brian S. Posner, a director of Dyne Therapeutics (DYN), purchased 3,000 shares in an open-market transaction on March 6, 2026. The reported weighted-average price was $15.06 per share, for a total reported purchase value of $45,180. This was a purchase (insider acquisition), which some investors view as more informative than routine sales, though motives are not disclosed.

Key Details

• Transaction date: 2026-03-06
• Transaction type/code: Open-market purchase (P)
• Price: Weighted average $15.06; actual trades ranged $14.96–$15.12 (footnote)
• Total value: $45,180
• Shares owned after transaction: Not disclosed in the provided filing
• Filing date/timeliness: Form 4 filed 2026-03-10 (filed within the SEC’s required 2 business days)
• Footnote: The $15.06 price is a weighted average; the filing states trades occurred at prices between $14.96 and $15.12 and that the reporting person will provide a breakdown on request.

Context

• This was an open-market purchase of common stock (code P). No option exercises, gifts, or 10b5-1 plans are referenced in the provided information. Purchases by directors are factual data points for investors but do not, by themselves, explain the insider’s motivation.