0000950170-23-073954.txt : 20231229 0000950170-23-073954.hdr.sgml : 20231229 20231229210307 ACCESSION NUMBER: 0000950170-23-073954 CONFORMED SUBMISSION TYPE: 144 PUBLIC DOCUMENT COUNT: 1 FILED AS OF DATE: 20231229 DATE AS OF CHANGE: 20231229 SUBJECT COMPANY: COMPANY DATA: COMPANY CONFORMED NAME: Dyne Therapeutics, Inc. CENTRAL INDEX KEY: 0001818794 STANDARD INDUSTRIAL CLASSIFICATION: PHARMACEUTICAL PREPARATIONS [2834] ORGANIZATION NAME: 03 Life Sciences IRS NUMBER: 364883909 STATE OF INCORPORATION: DE FISCAL YEAR END: 1231 FILING VALUES: FORM TYPE: 144 SEC ACT: 1933 Act SEC FILE NUMBER: 001-39509 FILM NUMBER: 231529234 BUSINESS ADDRESS: STREET 1: 1560 TRAPELO ROAD CITY: WALTHAM STATE: MA ZIP: 02451 BUSINESS PHONE: (781) 786-8230 MAIL ADDRESS: STREET 1: 1560 TRAPELO ROAD CITY: WALTHAM STATE: MA ZIP: 02451 REPORTING-OWNER: COMPANY DATA: COMPANY CONFORMED NAME: McNeill Jonathan CENTRAL INDEX KEY: 0001824673 ORGANIZATION NAME: FILING VALUES: FORM TYPE: 144 MAIL ADDRESS: STREET 1: C/O DYNE THERAPEUTICS, INC. STREET 2: 830 WINTER STREET CITY: WALTHAM STATE: MA ZIP: 02451 144 1 primary_doc.xml 144 0001824673 XXXXXXXX LIVE 0001818794 Dyne Therapeutics, Inc. 001-39509 1560 Trapelo Road Waltham MA 02451 (781)-786-8230 Jonathan McNeill Officer Common Stock Stifel Financial Corporation

3 Bryant Park, 4th Floor 1095 Avenue of the Americas New York NY 10036

11900 158270 61375598 01/02/2024 NASDAQ Common Stock 12/10/2022 Restricted stock units granted pursuant to Issuer's 2020 Stock Incentive Plan, subject to vesting requirements Issuer N 110 12/10/2022 N/A Common Stock 03/10/2023 Restricted stock units granted pursuant to Issuer's 2020 Stock Incentive Plan, subject to vesting requirements Issuer N 1606 03/10/2023 N/A Common Stock 06/10/2023 Restricted stock units granted pursuant to Issuer's 2020 Stock Incentive Plan, subject to vesting requirements Issuer N 1729 06/10/2023 N/A Common Stock 09/10/2023 Restricted stock units granted pursuant to Issuer's 2020 Stock Incentive Plan, subject to vesting requirements Issuer N 2816 09/10/2023 N/A Common Stock 09/17/2023 Restricted stock units granted pursuant to Issuer's 2020 Stock Incentive Plan, subject to vesting requirements Issuer N 2950 09/17/2023 N/A Common Stock 12/10/2023 Restricted stock units granted pursuant to Issuer's 2020 Stock Incentive Plan, subject to vesting requirements Issuer N 2689 12/10/2023 N/A N Jonathan McNeill

1560 Trapelo Road Waltham MA 02451

Common Stock 12/11/2023 1245 13346 The proposed sales reported in this Form 144 are to be effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on June 29, 2023. Securities sold on December 11, 2023 represent 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 10, 2021 and December 9, 2022. 12/29/2023 06/29/2023 /s/ Richard Scalzo, Attorney-in-Fact