Comparable stake leader
RA CAPITAL MANAGEMENT, L.P.
SEC ownership of Adicet Bio, Inc.
Top holders, 13D/G large-stake signals, insider positions, and transaction flow tied to CIK 0001720580.
Disclosed value leader
RA CAPITAL MANAGEMENT, L.P.
Comparable rows
50/50
Latest evidence
08 Apr 2026
- Public ticker
- ACET on Nasdaq
- Parsed ownership sources
-
13D/G, 3/4/5, and 13F
Source: Parsed SEC ownership filingsUse: Compare filing families carefully
- Largest SEC-reported holder
-
RA CAPITAL MANAGEMENT, L.P.
Ranking: Comparable ownership first, then disclosed value
- Comparable ownership rows
-
50 of 50
Meaning: Rows with safely comparable ownership %
- Latest 13D/G holder
-
RA CAPITAL MANAGEMENT, L.P.
Source: Latest parsed Schedule 13D/G stake
- Latest parsed ownership date
-
08 Apr 2026
Freshness: Most recent filing date in this holder set
- Issuer CIK
- 0001720580
- Issuer location
- Boston, MA
Ownership snapshot
CIK-linked ownership evidence from parsed SEC filings.
3 signals
Issuer
Names, identifiers, and filing context for this profile.
2 identity fields
Ownership snapshot
Top shareholders of Adicet 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
RA CAPITAL MANAGEMENT, L.P.
Disclosed value leader
RA CAPITAL MANAGEMENT, L.P.
Comparable rows
50/50
Latest evidence
08 Apr 2026
13D/G
3/4/5
13F
Lead comparable stake: 12%
13D/G row: RA CAPITAL MANAGEMENT, L.P.
Showing 1-8 of 50 holder rows.
Quick read
RA CAPITAL MANAGEMENT, L.P. leads the comparable SEC ownership view at 12%.
50 of 50 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.
Open SEC evidence
Opens RA CAPITAL MANAGEMENT, L.P.'s linked filing trail.
Comparable ownership
Top 5
RA CAPITAL MANAGEMENT, L.P.
12%
ORBIMED ADVISORS LLC
8.8%
FRANKLIN RESOURCES INC
6.5%
Woodline Partners LP
3.3%
TANG CAPITAL MANAGEMENT LLC
0.1%
Ownership % is shown only when SEC disclosures are safely comparable across share classes.
Detailed SEC evidence table Showing 1-8 of 50 holder rows
| Holder | Evidence | Ownership % | Position | 12M Net Δ | As of |
|---|---|---|---|---|---|
| RA CAPITAL MANAGEMENT, L.P. |
13D/G
3/4/5
13F
10%+ Owner · Company
|
12%
|
$8,834,201
1,182,624 shares
|
+$1,661,231 | 17 Feb 2026 |
| ORBIMED ADVISORS LLC |
13D/G
13F
Company
|
8.8%
|
$7,113,107
844,787 shares
|
-$117,272,169 | 08 Apr 2026 |
| FRANKLIN RESOURCES INC |
13D/G
13F
Company
|
6.5%
|
$5,238,572
626,571 shares
|
$0 | 31 Dec 2025 |
| Woodline Partners LP |
13D/G
13F
Company
|
3.3%
|
$2,132,374
313,124 shares
|
-$2,123,876 | 31 Mar 2026 |
| TANG CAPITAL MANAGEMENT LLC |
13D/G
|
0.1%
|
$51,050
6,158 shares
|
$0 | 31 Dec 2025 |
| CITADEL ADVISORS LLC |
13F
Company
|
4%
|
$2,600,215
381,823 shares
|
— | 31 Mar 2026 |
| VANGUARD CAPITAL MANAGEMENT LLC |
13F
Company
|
3.5%
|
$2,291,728
336,524 shares
|
— | 31 Mar 2026 |
| ADAGE CAPITAL PARTNERS GP, L.L.C. |
13F
Company
|
2.9%
|
$1,868,494
274,375 shares
|
— | 31 Mar 2026 |
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
Net insider flow leans to buying over the last 12 months. Net value: +$6,016,960.
Buys
$11,415,737
Insiders: 5
Sells
$5,398,776
Insiders: 8
Net
+$6,016,960
Shares: +5,057,120
Window
Last 12 months
4 rolling buckets
Buy value
Sell value
Shares: 5,894,384
Shares: 837,264
| Window (months) | Buy shares | Sell shares | Buy value | Sell value | Net value |
|---|---|---|---|---|---|
| 0-3 | 0 | 837,264 | $0 | $5,398,776 | -$5,398,776 |
| 3-6 | 894,384 | 0 | $6,415,737 | $0 | +$6,415,737 |
| 6-9 | 5,000,000 | 0 | $5,000,000 | $0 | +$5,000,000 |
| 9-12 | 0 | 0 | $0 | $0 | $0 |
Reporting owners
Insider holders from Forms 3/4/5
Showing 1-20 of 29 reporting-owner rows connected to Adicet Bio, Inc.. Open a relationship link for the CIK-to-CIK filing trail.
Rows
29
Largest Forms 3/4/5 holder
RA Capital Healthcare Fund LP
Net 12M change
+$6,016,960
Latest report
27 Apr 2026
| Name | Relationship | Holdings Value | Past Year Net Change | Change % | Valuation | Report Date |
|---|---|---|---|---|---|---|
| RA Capital Healthcare Fund LP | 10%+ Owner | $6,226,197 | +$1,603,934 | +35% | Mixed | 27 Apr 2026 |
| RA CAPITAL MANAGEMENT, L.P. | 10%+ Owner | $6,226,197 | +$1,603,934 | +35% | Mixed | 27 Apr 2026 |
| Rajeev M. Shah | 10%+ Owner | $6,226,197 | +$1,603,934 | +35% | Mixed | 27 Apr 2026 |
| Peter Kolchinsky | 10%+ Owner | $6,226,197 | +$1,603,934 | +35% | Mixed | 27 Apr 2026 |
| Carl L. Gordon | Director, 10%+ Owner | $941,594 | Mixed | 21 Aug 2024 | ||
| Francesco Galimi | SVP & Chief Medical Officer | $244,322 | Mixed | 05 Jun 2024 | ||
| Aya Jakobovits | Director | $214,323 | Mixed | 21 Aug 2024 | ||
| Lloyd Klickstein | Director | $66,225 | Mixed | 11 Jun 2025 | ||
| Chen Schor | President & CEO, Director | $59,296 | Mixed | 25 Mar 2026 | ||
| Brian Nicholas Harvey | Chief Financial Officer | $43,423 | Mixed | 25 Mar 2026 | ||
| Don Healey | Chief Technology Officer | $29,134 | Mixed | 25 Mar 2026 | ||
| Blake Aftab | Chief Scientific Officer | $25,159 | Mixed | 25 Mar 2026 | ||
| Steve Dubin | Director | $13,847 | Mixed | 11 Jun 2025 | ||
| Jeffrey Chodakewitz | Director | $10,797 | Mixed | 11 Jun 2025 | ||
| Andrew Sinclair | Director | $10,797 | Mixed | 11 Jun 2025 | ||
| Michael Kauffman | Director | $8,437 | Filing P/S | 21 Aug 2024 | ||
| Katie Peng | Director | $7,198 | Mixed | 11 Jun 2025 | ||
| OrbiMed Advisors Israel II Ltd | 10%+ Owner | $0 | -$674,847 | -100% | Mixed | 07 Apr 2026 |
| OrbiMed Israel GP Ltd. | 10%+ Owner | $0 | -$674,847 | -100% | Mixed | 07 Apr 2026 |
| ORBIMED ADVISORS LLC | 10%+ Owner | $0 | +$4,325,153 | Mixed | 07 Apr 2026 |
Recent insider transactions for Adicet 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| RA CAPITAL MANAGEMENT, L.P. | ACET | Common Stock | Other | -21.1% | -250,000 | 932,624 | 27 Apr 2026 | See footnotes | ||
| RA CAPITAL MANAGEMENT, L.P. | ACET | Common Stock | Other | -21.1% | -250,000 | 932,624 | 27 Apr 2026 | See footnotes | ||
| Ra Capital Management, L.P. | ACET | Common Stock | Other | -21.1% | -250,000 | 932,624 | 27 Apr 2026 | See footnotes | ||
| Ra Capital Management, L.P. | ACET | Common Stock | Other | -21.1% | -250,000 | 932,624 | 27 Apr 2026 | See footnotes | ||
| RA CAPITAL MANAGEMENT, L.P. | ACET | Pre-Funded Warrant (Right to Buy) | Other | 21.7% | 250,000 | 1,402,833 | 27 Apr 2026 | See footnotes | ||
| RA CAPITAL MANAGEMENT, L.P. | ACET | Pre-Funded Warrant (Right to Buy) | Other | 21.7% | 250,000 | 1,402,833 | 27 Apr 2026 | See footnotes | ||
| Ra Capital Management, L.P. | ACET | Pre-Funded Warrant (Right to Buy) | Other | 21.7% | 250,000 | 1,402,833 | 27 Apr 2026 | See footnotes | ||
| Ra Capital Management, L.P. | ACET | Pre-Funded Warrant (Right to Buy) | Other | 21.7% | 250,000 | 1,402,833 | 27 Apr 2026 | See footnotes | ||
| Orbimed Advisors Llc | ACET | Common Stock | Sale | -100% | $468,082 | $6.42 | -72,939 | 0 | 08 Apr 2026 | See footnotes |
| Orbimed Advisors Llc | ACET | Common Stock | Sale | -100% | $468,082 | $6.42 | -72,939 | 0 | 08 Apr 2026 | See footnotes |
| ORBIMED ADVISORS LLC | ACET | Common Stock | Sale | -100% | $468,082 | $6.42 | -72,939 | 0 | 08 Apr 2026 | See footnotes |
| Orbimed Advisors Llc | ACET | Common Stock | Sale | -100% | $468,082 | $6.42 | -72,939 | 0 | 08 Apr 2026 | See footnotes |
| Orbimed Advisors Llc | ACET | Common Stock | Sale | -100% | $468,082 | $6.42 | -72,939 | 0 | 08 Apr 2026 | See footnotes |
| Orbimed Advisors Llc | ACET | Common Stock | Sale | -100% | $468,082 | $6.42 | -72,939 | 0 | 08 Apr 2026 | See footnotes |
| Orbimed Advisors Llc | ACET | Common Stock | Sale | -100% | $468,082 | $6.42 | -72,939 | 0 | 08 Apr 2026 | See footnotes |
| Orbimed Advisors Llc | ACET | Common Stock | Sale | -100% | $468,082 | $6.42 | -72,939 | 0 | 08 Apr 2026 | See footnotes |
| Orbimed Advisors Llc | ACET | Common Stock | Sale | -49.4% | $206,765 | $6.52 | -31,719 | 32,523 | 07 Apr 2026 | See footnotes |
| Orbimed Advisors Llc | ACET | Common Stock | Sale | -49.4% | $206,765 | $6.52 | -31,719 | 32,523 | 07 Apr 2026 | See footnotes |
| ORBIMED ADVISORS LLC | ACET | Common Stock | Sale | -49.4% | $206,765 | $6.52 | -31,719 | 32,523 | 07 Apr 2026 | See footnotes |
| Orbimed Advisors Llc | ACET | Common Stock | Sale | -49.4% | $206,765 | $6.52 | -31,719 | 32,523 | 07 Apr 2026 | See footnotes |
| Orbimed Advisors Llc | ACET | Common Stock | Sale | -49.4% | $206,765 | $6.52 | -31,719 | 32,523 | 07 Apr 2026 | See footnotes |
| Orbimed Advisors Llc | ACET | Common Stock | Sale | -49.4% | $206,765 | $6.52 | -31,719 | 32,523 | 07 Apr 2026 | See footnotes |
| Orbimed Advisors Llc | ACET | Common Stock | Sale | -49.4% | $206,765 | $6.52 | -31,719 | 32,523 | 07 Apr 2026 | See footnotes |
| Orbimed Advisors Llc | ACET | Common Stock | Sale | -49.4% | $206,765 | $6.52 | -31,719 | 32,523 | 07 Apr 2026 | See footnotes |
| Brian Nicholas Harvey | ACET | Stock Option (Right to Buy) | Award | 43,361 | 43,361 | 25 Mar 2026 | Direct | |||
| Chen Schor | ACET | Stock Option (Right to Buy) | Award | 468,555 | 468,555 | 25 Mar 2026 | Direct | |||
| Julia D. Maltzman | ACET | Stock Option (Right to Buy) | Award | 72,555 | 72,555 | 25 Mar 2026 | Direct | |||
| Don Healey | ACET | Stock Option (Right to Buy) | Award | 43,361 | 43,361 | 25 Mar 2026 | Direct | |||
| Blake Aftab | ACET | Stock Option (Right to Buy) | Award | 72,555 | 72,555 | 25 Mar 2026 | Direct | |||
| RA CAPITAL MANAGEMENT, L.P. | ACET | Common Stock | Purchase | 6.75% | $543,440 | $7.27 | 74,751 | 1,182,624 | 20 Feb 2026 | See footnotes |
| RA CAPITAL MANAGEMENT, L.P. | ACET | Common Stock | Purchase | 6.75% | $543,440 | $7.27 | 74,751 | 1,182,624 | 20 Feb 2026 | See footnotes |
| Ra Capital Management, L.P. | ACET | Common Stock | Purchase | 6.75% | $543,440 | $7.27 | 74,751 | 1,182,624 | 20 Feb 2026 | See footnotes |
| Ra Capital Management, L.P. | ACET | Common Stock | Purchase | 6.75% | $543,440 | $7.27 | 74,751 | 1,182,624 | 20 Feb 2026 | See footnotes |
| RA CAPITAL MANAGEMENT, L.P. | ACET | Common Stock | Purchase | 7.19% | $535,472 | $7.21 | 74,268 | 1,107,873 | 19 Feb 2026 | See footnotes |
| RA CAPITAL MANAGEMENT, L.P. | ACET | Common Stock | Purchase | 7.19% | $535,472 | $7.21 | 74,268 | 1,107,873 | 19 Feb 2026 | See footnotes |
| Ra Capital Management, L.P. | ACET | Common Stock | Purchase | 7.19% | $535,472 | $7.21 | 74,268 | 1,107,873 | 19 Feb 2026 | See footnotes |
| Ra Capital Management, L.P. | ACET | Common Stock | Purchase | 7.19% | $535,472 | $7.21 | 74,268 | 1,107,873 | 19 Feb 2026 | See footnotes |
| RA CAPITAL MANAGEMENT, L.P. | ACET | Common Stock | Purchase | 7.78% | $525,022 | $7.04 | 74,577 | 1,033,605 | 18 Feb 2026 | See footnotes |
| RA CAPITAL MANAGEMENT, L.P. | ACET | Common Stock | Purchase | 7.78% | $525,022 | $7.04 | 74,577 | 1,033,605 | 18 Feb 2026 | See footnotes |
| Ra Capital Management, L.P. | ACET | Common Stock | Purchase | 7.78% | $525,022 | $7.04 | 74,577 | 1,033,605 | 18 Feb 2026 | See footnotes |
| Ra Capital Management, L.P. | ACET | Common Stock | Purchase | 7.78% | $525,022 | $7.04 | 74,577 | 1,033,605 | 18 Feb 2026 | See footnotes |
| Blake Aftab | ACET | Common Stock | Tax liability | -15.2% | -535 | 2,981 | 24 Jan 2026 | Direct | ||
| Don Healey | ACET | Common Stock | Tax liability | -13.4% | -535 | 3,452 | 24 Jan 2026 | Direct | ||
| Brian Nicholas Harvey | ACET | Common Stock | Tax liability | -9.59% | -546 | 5,145 | 24 Jan 2026 | Direct | ||
| Chen Schor | ACET | Common Stock | Tax liability | -20.5% | -1,755 | 6,820 | 24 Jan 2026 | Direct | ||
| Orbimed Advisors Llc | ACET | Common Stock | Purchase | 124.2% | $5,000,000 | $1.00 | 5,000,000 | 9,026,359 | 08 Oct 2025 | See footnotes |
* marks a reported price that did not pass the local price check.