Cox John 4
4 · Dyne Therapeutics, Inc. · Filed May 14, 2026
Research Summary
AI-generated summary of this filing
Dyne Therapeutics (DYN) CEO John Cox Sells 3,311 Shares
What Happened
- John Cox, CEO and President (and a director) of Dyne Therapeutics (DYN), sold 3,311 shares in an open-market/automatic sale on May 13, 2026. The weighted average sale price was $18.36 per share, resulting in proceeds of roughly $60,790. The sale was to satisfy tax withholding obligations tied to the vesting of restricted stock units (RSUs).
Key Details
- Transaction date: 2026-05-13; weighted average price reported $18.36 (sales executed in the $18.20–$18.41 range).
- Total shares sold: 3,311; total proceeds ≈ $60,790. Reporting person can provide breakdown of shares sold at each price upon request.
- Purpose: Automatic sale to cover tax withholding on RSUs vested Feb 12, 2026 (per RSU agreement); described as a non-discretionary sale consistent with the affirmative defense under Rule 10b5-1.
- Holdings note: Filing references 268,645 unvested RSUs included in the reporting person's holdings; some shares are held in a trust for a child. The filing does not state a full post-transaction total share count in the provided excerpt.
- Filing timing: Report filed May 14, 2026 for the May 13 transaction (appears timely).
Context
- This was an automatic, tax-withholding sale tied to RSU vesting rather than an independent sale decision by the insider; such transactions are common and not necessarily a signal of sentiment. The amounts involved are modest relative to large insider buys/sells.
Insider Transaction Report
Form 4
Cox John
DirectorCEO & President
Transactions
- Sale
Common Stock
[F1][F2][F3]2026-05-13$18.36/sh−3,311$60,790→ 370,834 total
Holdings
- 18,000(indirect: By Trust)
Common Stock
[F4] - 18,000(indirect: By Trust)
Common Stock
[F4] - 18,000(indirect: By Trust)
Common Stock
[F4] - 18,000(indirect: By Trust)
Common Stock
[F4]
Footnotes (4)
- [F1]Represents shares automatically sold by the Reporting Person to satisfy tax withholding obligations in connection with the vesting of restricted stock units granted to the Reporting Person on February 12, 2026. The automatic sale of the Reporting Person's shares is provided for in a restricted stock unit agreement constituting a "binding contract" consistent with the affirmative defense to liability under Rule 10b5-1 and the sale does not represent a discretionary trade by the Reporting Person.
- [F2]The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices within the range of $18.20 to $18.41, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote of this Form 4.
- [F3]Includes 268,645 unvested RSUs.
- [F4]These shares are held in a trust for the benefit of a child of the Reporting Person.
Signature
/s/ Ron Caponigro, Attorney-in-Fact|2026-05-14