Dyne CEO sells 2,683 shares in tax-driven sale
Dyne Therapeutics, Inc. CEO and President John Cox reported an automatic sale of 2,683 shares of common stock on June 16, 2026 at a weighted average price of $18.33 per share.
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Form Type
4
Rhea-AI Filing Summary
Dyne Therapeutics, Inc. CEO and President John Cox reported an automatic sale of 2,683 shares of common stock on June 16, 2026 at a weighted average price of $18.33 per share. According to the disclosure, the shares were sold to satisfy tax withholding obligations related to the vesting of restricted stock units granted on December 4, 2024, under a binding contract consistent with the Rule 10b5-1 affirmative defense, meaning the sale was not a discretionary trade. Following this transaction, Cox directly holds 368,151 shares, including 259,564 unvested RSUs, and indirectly holds 18,000 shares in each of four trusts for the benefit of a child.
Insider Trade Summary 10b5-1
Net Seller: 2,683 shares
Net Sell
5 txns
Insider
Cox John
Role
CEO & President
Sold
2,683 shs ($49K)
| Type | Security | Shares | Price | Value |
|---|---|---|---|---|
| Sale | Common Stock | 2,683 | $18.33 | $49K |
| holding | Common Stock | -- | -- | -- |
| holding | Common Stock | -- | -- | -- |
| holding | Common Stock | -- | -- | -- |
| holding | Common Stock | -- | -- | -- |
Holdings After Transaction:
Common Stock — 368,151 shares (Direct);
Common Stock — 18,000 shares (Indirect, By Trust #1);
Common Stock — 18,000 shares (Indirect, By Trust #2);
Common Stock — 18,000 shares (Indirect, By Trust #3);
Common Stock — 18,000 shares (Indirect, By Trust #4)
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.
Key Figures
Shares sold: 2,683 shares
Weighted average sale price: $18.33 per share
Direct holdings after transaction: 368,151 shares
+2 more
5 metrics
Shares sold
2,683 shares
Automatic sale on June 16, 2026
Weighted average sale price
$18.33 per share
Open-market sale range $18.00–$18.70
Direct holdings after transaction
368,151 shares
Common stock held directly by CEO after sale
Unvested RSUs included
259,564 RSUs
Unvested restricted stock units within direct holdings
Trust holdings per trust
18,000 shares
Common stock held indirectly in each of four trusts
Key Terms
restricted stock units, tax withholding obligations, Rule 10b5-1, weighted average price, +1 more
5 terms
restricted stock units financial
"vesting of restricted stock units granted to the Reporting Person on December 4, 2024"
Restricted stock units are a type of company reward where employees are promised shares of stock, but they only fully own these shares after meeting certain conditions, like staying with the company for a set time. They matter because they can become valuable assets and are often used to motivate employees to help the company succeed.
tax withholding obligations financial
"shares automatically sold by the Reporting Person to satisfy tax withholding obligations"
Rule 10b5-1 regulatory
"binding contract consistent with the affirmative defense to liability under Rule 10b5-1"
Rule 10b5-1 is a regulation that allows company insiders to buy or sell their shares at predetermined times, even if they have access to non-public information. It acts like setting a schedule in advance for transactions, helping prevent accusations of unfair trading. This rule provides a way for insiders to plan trades transparently, giving investors confidence that these transactions are not based on hidden information.
weighted average price financial
"The price reported in Column 4 is a weighted average price."
Weighted average price is the average price of a security where each trade or component is counted according to its size, so bigger trades pull the average more than smaller ones. Think of it like calculating the average cost of a grocery haul where items you bought more of have greater influence on the final per-item cost. Investors use it to understand the true average price paid or received, judge execution quality, and compare trading performance against market movement.
unvested RSUs financial
"Includes 259,564 unvested RSUs."
FAQ
AI-generated questions and answers. How Rhea-AI works. Not financial advice.
What insider transaction did Dyne Therapeutics (DYN) report for CEO John Cox?
Dyne Therapeutics reported that CEO John Cox automatically sold 2,683 shares of common stock. The sale occurred on June 16, 2026 at a weighted average price of $18.33 per share to cover tax withholding obligations tied to vested restricted stock units.
What is the role of restricted stock units in the Dyne Therapeutics (DYN) CEO’s transaction?
The sale was triggered by the vesting of restricted stock units granted on December 4, 2024. Shares were automatically sold to cover tax withholding obligations from that vesting, and the CEO’s remaining direct holdings include 259,564 unvested RSUs as part of his equity compensation.
How are trust holdings described in the Dyne Therapeutics (DYN) CEO Form 4?
The Form 4 lists four indirect holdings of 18,000 Dyne Therapeutics shares each, identified as Trust #1 through Trust #4. A footnote explains these shares are held in a trust for the benefit of a child of the reporting person, indicating estate or family planning structures.
AI-generated analysis. How Rhea-AI works. Not financial advice.
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