Posner Brian S 4

What Happened

• Brian S. Posner, a director of Dyne Therapeutics (DYN), purchased 2,000 shares in an open-market transaction on March 11, 2026. The shares were acquired at $19.35 per share for a total of $38,700. This was a purchase (transaction code P), which increases his personal equity stake in the company.

Key Details

• Transaction date and price: 2026-03-11, 2,000 shares at $19.35 each.
• Total value: $38,700.
• Shares owned after transaction: Not specified in the provided filing excerpt.
• Footnotes/plan details: No 10b5-1 plan, tax-withholding, or other special footnotes were reported in the information provided.
• Timeliness: The Form 4 was filed on 2026-03-13 for the 2026-03-11 transaction — filed within the standard two-business-day window (not marked late).

Context

• This was an open-market purchase, meaning the director bought shares on the public market rather than receiving them as an award or exercising options. Purchases by insiders are often watched by investors for informational value, but they do not guarantee future stock performance.