Cox John 4
4 · Dyne Therapeutics, Inc. · Filed Jun 17, 2026
Research Summary
AI-generated summary of this filing
Dyne Therapeutics CEO John Cox Sells 2,683 Shares
What Happened
John Cox, CEO & President and a director of Dyne Therapeutics (DYN), disposed of 2,683 shares on June 16, 2026. The filing reports a weighted-average price of $18.33 (sales executed in the $18.00–$18.70 range), for total gross proceeds of approximately $49,179. The sale was an automatic disposition to satisfy tax withholding obligations related to the vesting of restricted stock units (RSUs) granted on December 4, 2024, and was not a discretionary trade.
Key Details
- Transaction date: 2026-06-16; Form 4 filed 2026-06-17 (timely).
- Action: Sale (code S) of 2,683 shares; weighted-average price $18.33; price range $18.00–$18.70; proceeds ≈ $49,179. (Footnote F2: price is weighted average; breakdown available on request.)
- Reason: Automatic sale to satisfy tax withholding on vested RSUs (Footnote F1). The RSU agreement provides for automatic sale and is treated as a binding contract consistent with a Rule 10b5-1 affirmative defense.
- Ownership after transaction: filing notes 259,564 unvested RSUs (Footnote F3); total post-sale share count not specified in the provided excerpt.
- Additional note: Some shares are held in a trust for the benefit of a child of the reporting person (Footnote F4).
Context
This was a tax-withholding sale tied to RSU vesting—common and generally considered routine rather than a signal of negative sentiment. The filing emphasizes the sale was automatic under the RSU agreement and not a discretionary trade. Retail investors typically weigh purchases more heavily than routine withholding sales when interpreting insider activity.
Insider Transaction Report
- Sale
Common Stock
[F1][F2][F3]2026-06-16$18.33/sh−2,683$49,179→ 368,151 total
- 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 December 4, 2024. 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 $18.00 to $18.70, 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 259,564 unvested RSUs.
- [F4]These shares are held in a trust for the benefit of a child of the Reporting Person.