Changes in Beneficial Ownership · 4
Dyne Therapeutics, Inc.
DYNNASDAQEQUITYCurrent
Changes in Beneficial Ownership
Structured filing — 4
ownership.xml
Filing details
- Report period
- 2026-09-08
- Issuer
- Dyne Therapeutics, Inc.
- Issuer CIK
- 0001818794
- Trading symbol
- DYN
- Rule 10b5-1 indication
- Checked
Reporting owner 1
- Name
- Cox John
- Reporting owner CIK
- 0001498428
- Relationship
- Director · Officer
- Officer title
- CEO & President
- Address
- C/O DYNE THERAPEUTICS, INC., 1560 TRAPELO ROAD, WALTHAM, MA, 02451
Non-derivative transactions
| Security | Transaction date | Code | Amount | A / D | Price (USD) | Owned after | Ownership |
|---|---|---|---|---|---|---|---|
| Common Stock | 2026-09-08 | S · Form 4[F1] | 5,658 | D | 18.88[F2] | 357,507[F3] | D |
Table key
- S · Form 4
- Sale on the market or privately
- D
- Direct
Non-derivative holdings
| Security | Amount owned | Ownership | Nature of ownership |
|---|---|---|---|
| Common Stock | 18,000 | I | By Trust #1[F4] |
| Common Stock | 18,000 | I | By Trust #2[F4] |
| Common Stock | 18,000 | I | By Trust #3[F4] |
| Common Stock | 18,000 | I | By Trust #4[F4] |
Table key
- I
- Indirect
Footnotes
- 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.↩ 1
- 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 $18.77 to $18.92, 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.↩ 1
- F3
- Includes 239,233 unvested RSUs.↩ 1
Signature 1
- Signed
- /s/ Ron Caponigro, Attorney-in-Fact
- Date
- 2026-09-08
Company context
Dyne Therapeutics is focused on delivering functional improvement for people living with genetically driven neuromuscular diseases. We are developing therapeutics that target muscle and the central nervous system (CNS) to address the root cause of disease. The company is advancing clinical programs for Duchenne muscular dystrophy (DMD) and myotonic dystrophy type 1 (DM1) as well as preclinical programs for facioscapulohumeral muscular dystrophy (FSHD), Pompe disease and multiple DMD mutations. At Dyne, we are on a mission to deliver functional improvement for individuals, families and communities. Learn more at https://www.dyne-tx.com/, and follow us on X, LinkedIn and Facebook.