Comparable stake leader
VANGUARD GROUP INC
SEC ownership of 2seventy bio, Inc.
Top holders, 13D/G large-stake signals, insider positions, and transaction flow tied to CIK 0001860782.
Disclosed value leader
Kynam Capital Management, LP
Comparable rows
2/17
Latest evidence
30 Jun 2025
- SEC evidence covered
- 13D/G and 3/4/5
- Largest SEC-reported holder
- VANGUARD GROUP INC
- Latest 13D/G holder
- VANGUARD GROUP INC
- Latest parsed evidence date
- 30 Jun 2025
- CIK
- 0001860782
- Location
- Cambridge, MA
Ownership snapshot
2 signals
Issuer
2 identity fields
Ownership snapshot
Top shareholders of 2seventy bio, Inc. (13F + 13D/G + 3/4/5)
Grouped by holder across the latest SEC ownership disclosures. Start with comparable ownership when available, then verify the linked 13F, 13D/G, or 3/4/5 evidence.
Comparable stake leader
VANGUARD GROUP INC
Disclosed value leader
Kynam Capital Management, LP
Comparable rows
2/17
Latest evidence
30 Jun 2025
13D/G
3/4/5
Lead comparable stake: 5.4%
15 rows are not safely comparable across share classes.
13D/G row: VANGUARD GROUP INC
Showing 1-8 of 17 holder rows.
Quick read
VANGUARD GROUP INC leads the comparable SEC ownership view at 5.4%.
2 of 17 rows have a safely comparable ownership percentage. Use this as a filing-backed starting point, then open the detailed table for source links, reporting role, position value, share count, and filing date.
Comparable ownership
Top 2
VANGUARD GROUP INC
5.4%
GOLDMAN SACHS GROUP INC
0%
Ownership % is shown only when SEC disclosures are safely comparable across share classes.
Detailed SEC evidence table Showing 1-8 of 17 holder rows
| Holder | Evidence | Ownership % | Position | 12M Net Δ | As of |
|---|---|---|---|---|---|
| VANGUARD GROUP INC |
13D/G
The Vanguard Group
|
5.4%
|
$14,069,150
2,819,469 shares
|
$0 | 31 Mar 2025 |
| GOLDMAN SACHS GROUP INC |
13D/G
THE GOLDMAN SACHS GROUP, INC.
|
0%
|
$1,531
308 shares
|
$0 | 30 Jun 2025 |
| Kynam Capital Management, LP |
3/4/5
10%+ Owner
|
—
class O/S missing
|
$61,293,964
10,284,222 shares
|
— | 10 Aug 2023 |
| Casdin Capital, LLC |
3/4/5
Director
|
—
mixed-class rows
|
$12,893,491
2,571,459 shares
mixed-class rows
|
— | 13 May 2025 |
| Philip D. Gregory |
3/4/5
Chief Scientific Officer
|
—
mixed-class rows
|
$1,789,046
469,155 shares
mixed-class rows
|
— | 05 Jan 2024 |
| William D. Baird III |
3/4/5
President and CEO, Director
|
—
class O/S missing
|
$691,680
176,000 shares
|
— | 13 May 2025 |
| Nicola Heffron |
3/4/5
Chief Operating Officer
|
—
class O/S missing
|
$334,754
89,182 shares
|
— | 07 Feb 2023 |
| Victoria Eatwell |
3/4/5
Chief Financial Officer
|
—
class O/S missing
|
$282,960
72,000 shares
|
— | 13 May 2025 |
How to read this table
Rows are grouped by holder and ranked first by SEC-reported ownership % when it is safely comparable, then by disclosed holdings value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.
Forms 3/4/5 flow
Insider trading overview
Insider buy and sell flow is broadly balanced over the last 12 months. No Buy or Sell transactions have been reported since 02 Jun 2025.
Buys
$0
Insiders: 0
Sells
$0
Insiders: 0
Net
$0
Shares: 0
Window
Last 12 months
4 rolling buckets
Buy value
Sell value
Shares: 0
Shares: 0
| Window (months) | Buy shares | Sell shares | Buy value | Sell value | Net value |
|---|---|---|---|---|---|
| 0-3 | 0 | 0 | $0 | $0 | $0 |
| 3-6 | 0 | 0 | $0 | $0 | $0 |
| 6-9 | 0 | 0 | $0 | $0 | $0 |
| 9-12 | 0 | 0 | $0 | $0 | $0 |
Reporting owners
Insider holders from Forms 3/4/5
Showing 1-18 of 18 reporting-owner rows connected to 2seventy bio, Inc.. Open a relationship link for the CIK-to-CIK filing trail.
Rows
18
Largest Forms 3/4/5 holder
Kynam Capital Management, LP
Net 12M change
$0
Latest report
13 May 2025
| Name | Relationship | Holdings Value | Past Year Net Change | Change % | Valuation | Report Date |
|---|---|---|---|---|---|---|
| Kynam Capital Management, LP | 10%+ Owner | $61,293,964 | Filing P/S | 10 Aug 2023 | ||
| Casdin Capital, LLC | Director | $12,893,491 | Mixed | 13 May 2025 | ||
| Philip D. Gregory | Chief Scientific Officer | $1,789,046 | Mixed | 05 Jan 2024 | ||
| William D. Baird III | President and CEO, Director | $691,680 | Mixed | 13 May 2025 | ||
| Nicola Heffron | Chief Operating Officer | $334,754 | Mixed | 07 Feb 2023 | ||
| Victoria Eatwell | Chief Financial Officer | $282,960 | Mixed | 13 May 2025 | ||
| Jessica Snow | Chief Operating Officer | $278,048 | Mixed | 13 May 2025 | ||
| Daniel Lynch | Director | $145,442 | Mixed | 13 Jun 2023 | ||
| Ramy Ibrahim | Director | $137,923 | Mixed | 13 Jun 2023 | ||
| Marcela Maus V | Director | $94,713 | Mixed | 13 May 2025 | ||
| Sarah Js Glickman | Director | $94,713 | Mixed | 13 May 2025 | ||
| Wei Lin | Director | $94,713 | Mixed | 13 May 2025 | ||
| Denice Torres | Director | $94,713 | Mixed | 13 May 2025 | ||
| Charles W. Newton | Director | $47,357 | Mixed | 13 May 2025 | ||
| William R. Sellers | Director | $24,670 | Mixed | 11 Nov 2021 | ||
| Kynam Global Healthcare Master Fund, LP | 10%+ Owner | $0 | Mixed | 11 Mar 2025 | ||
| Nick Leschly | Director | $0 | Mixed | 13 May 2025 | ||
| bluebird bio, Inc. | 10%+ Owner | Mixed | 03 Nov 2021 |
Recent insider transactions for 2seventy bio, Inc.
Showing up to 300 recent insider transactions from the last 12 months.
| Insider | Symbol | Class | Transaction | % | SEC-reported value | SEC-reported price | Shares | Shares owned | Date | Ownership |
|---|---|---|---|---|---|---|---|---|---|---|
| No insider transactions were found in the last 12 months for this issuer. | ||||||||||
* marks a reported price that did not pass the local price check.