Dyne Therapeutics, Inc. (DYN) insider trading

{
  "status": "OK",
  "results": [
    {
      "tickers": [
        "DYN"
      ],
      "issuer_cik": "0001818794",
      "owner_cik": "0001372455",
      "accession_number": "0001193125-26-415584",
      "form_type": "4",
      "filing_date": "2026-10-06",
      "period_of_report": "2026-10-02",
      "issuer_name": "Dyne Therapeutics, Inc.",
      "issuer_trading_symbol": "DYN",
      "owner_name": "Posner Brian S",
      "is_director": true,
      "is_officer": false,
      "is_ten_percent_owner": false,
      "is_other": false,
      "security_type": "non_derivative",
      "record_type": "transaction",
      "security_title": "Common Stock",
      "transaction_timeliness": "O",
      "aff_10b5_one": false,
      "transaction_date": "2026-10-02",
      "transaction_code": "P",
      "equity_swap_involved": false,
      "transaction_shares": 2500,
      "transaction_price_per_share": 16,
      "transaction_acquired_disposed": "A",
      "shares_owned_following_transaction": 27000,
      "transaction_value": 40000,
      "direct_or_indirect": "D"
    },
    {
      "tickers": [
        "DYN"
      ],
      "issuer_cik": "0001818794",
      "owner_cik": "0001577014",
      "accession_number": "0001577014-26-000016",
      "form_type": "4",
      "filing_date": "2026-08-17",
      "period_of_report": "2026-08-13",
      "issuer_name": "Dyne Therapeutics, Inc.",
      "issuer_trading_symbol": "DYN",
      "owner_name": "Rhodes Jason P",
      "is_director": true,
      "is_officer": false,
      "is_ten_percent_owner": false,
      "is_other": false,
      "security_type": "non_derivative",
      "record_type": "transaction",
      "security_title": "Common Stock",
      "transaction_timeliness": "O",
      "aff_10b5_one": true,
      "transaction_date": "2026-08-14",
      "transaction_code": "S",
      "equity_swap_involved": false,
      "transaction_shares": 322465,
      "transaction_price_per_share": 25,
      "transaction_acquired_disposed": "D",
      "shares_owned_following_transaction": 428946,
      "transaction_value": 8061625,
      "direct_or_indirect": "I",
      "nature_of_ownership": "See footnote",
      "footnotes": [
        {
          "id": "F1",
          "description": "Shares were sold pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on July 13, 2026."
        },
        {
          "id": "F6",
          "description": "The price reported in Column 4 is a weighted average price. These securities were sold in multiple transactions at prices ranging from $25.00 to $25.8916 inclusive."
        },
        {
          "id": "F5",
          "description": "The shares are held directly by Atlas Venture Opportunity Fund I, L.P. (\"AVOF I\"). The general partner of AVOF I is Atlas Venture Associates Opportunity I, L.P. (\"AVAO I LP\"). Atlas Venture Associates Opportunity I, LLC (\"AVAO I LLC\") is the general partner of AVAO I LP. The Reporting Person is a member of AVAO I LLC and disclaims Section 16 beneficial ownership of such securities held by AVOF I, except to the extent of his pecuniary interest therein, if any."
        }
      ]
    }
  ]
}

// trimmed to 2 results

The response includes every Form 4 record; this page keeps open-market purchases and sales on common stock and removes duplicate joint-filer rows.