DYN — blockholders· DYNE THERAPEUTICS, INC.
Everyone who has reported crossing 5% of this issuer inside the capture window — Schedule 13D (active intent, with its Item-4 purpose) and Schedule 13G (passive by rule) kept apart — each with its full amendment chain and, in the fold, the cover page's sole and shared voting and dispositive power per reporting person. Percents are each group's own as-filed figures and do not add up across filers: two filers can report the same shares.
Filed passively under Rule 13d-1(b) (qualified institution), (c) (passive investor) or (d) (exempt). A 13G filer is not an activist and files no purpose statement.
| Filer | Form | % of class | Change | Shares | Filed | Chain | Control | Filing |
|---|---|---|---|---|---|---|---|---|
| T. Rowe Price Investment Management, Inc. | 13G/A No. 2QII | 18.7% | ▲ +2.5pp | 30,785,801 | 2026-05-15 | 3 | SEC ↗ | |
| JANUS HENDERSON GROUP Ltd. | 13G/A No. 7QII | 7.3% | ▼ -1pp | 11,997,738 | 2026-08-13 | 7 | SEC ↗ | |
| BlackRock, Inc. | 13G/A No. 3QII | 7% | ▲ +1.2pp | 11,489,504 | 2026-07-28 | 2 | SEC ↗ | |
| FMR LLC | 13G/A No. 1QII | 6.8% | ▲ +1.4pp | 11,207,000 | 2026-08-06 | 4 | SEC ↗ | |
| ForDyne B.V. | 13G/A No. 2Exempt | 4.8% | first captured | 5,400,545 | 2025-05-15 | 1 | SEC ↗ | |
| Atlas Venture Fund XI, L.P. | 13G/A No. 6Exempt | 2.4% | ▼ -1.6pp | 4,479,449 | 2026-08-13 | 2 | SEC ↗ | |
| Point72 Asset Management, L.P. | 13G/A No. 1Passive | 1.5% | ▼ -3.6pp | 1,669,342 | 2025-05-15 | 2 | SEC ↗ | |
| RTW Investments, LP | 13G/A No. 2QII | 1.5% | ▼ -3.6pp | 1,690,567 | 2025-05-15 | 2 | SEC ↗ | |
| RA Capital Management, L.P. | 13G/A No. 3Passive | 0% | EXITED | 0 | 2025-11-14 | 2 | SEC ↗ | |
| The Vanguard Group | 13G/A No. 2QII | 0% | first captured | 0 | 2026-03-26 | 1 | SEC ↗ |
Source: SEC EDGAR Schedule 13D/G structured XML (public domain) · newest filing 2026-08-13 · capture 2024-01-10 → 2026-08-21 reported positions only — not a portfolio
Voting is not disposition. Each reporting person's cover page splits its holding into VOTING power (sole / shared) and DISPOSITIVE power (sole / shared). Voting and dispositive totals are summed WITHIN a person only — never across persons, because a group's members report overlapping interests in the same shares and the filing's aggregate is not their sum. Where a person's voting total is below its reported aggregate, the difference is shares it reports beneficial ownership of with no voting power reported; it is shown as a gap, never as a second position.
Percent is as filed. Percent is the filing's own percent of class, as filed (0–100). It's the reporting group's figure — not summed across filers, not recomputed against shares outstanding, not rescaled. Share counts are as filed and never subtracted across filings (a split would make that meaningless); the only change we show is the change in the as-filed percent against the prior captured filing.
We never call an amendment “new”. A filing is 'first captured' when we hold nothing earlier for that company + filer. On an amendment that means the original predates our window, not that the position is new — so we never badge an amendment 'new,' even when the raw data says so.
Escalations. An escalation is a filer moving from a passive 13G to an active 13D on the same company — telling the SEC it may now seek to influence control. It's a lower bound: a 13G filed before our window began is invisible and never guessed. If the 13D leg is a 13D/A, an earlier 13D predates our window, so the crossing shown is the first one visible inside it, not necessarily the filer's first.
Parsed Schedule 13D/G XML (events.db schedule_13dg + schedule_13dg_persons). 13D = active intent; 13G filers report passively under Rule 13d-1(b) QII / (c) Passive / (d) Exempt and are never activists. Percents are the reporting group's own as-filed figures and are NOT additive across filers — two filers can report the same shares. Structured 13D/13G coverage starts December 2024 (SEC XML mandate).