Comparable stake leader
Anna Berkenblit
SEC ownership of ImmunoGen, Inc.
Top holders, 13D/G large-stake signals, insider positions, and transaction flow tied to CIK 0000855654.
Disclosed value leader
Anna Berkenblit
Comparable rows
0/7
Latest evidence
12 Feb 2024
- Parsed ownership sources
-
3/4/5
Source: Parsed SEC ownership filingsUse: Compare filing families carefully
- Largest SEC-reported holder
-
Anna Berkenblit
Ranking: Comparable ownership first, then disclosed value
- Latest parsed ownership date
-
12 Feb 2024
Freshness: Most recent filing date in this holder set
- Issuer CIK
- 0000855654
- Issuer location
- Waltham, MA
Ownership snapshot
CIK-linked ownership evidence from parsed SEC filings.
1 signal
Issuer
Names, identifiers, and filing context for this profile.
2 identity fields
Ownership snapshot
Top shareholders of ImmunoGen, 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
Anna Berkenblit
Disclosed value leader
Anna Berkenblit
Comparable rows
0/7
Latest evidence
12 Feb 2024
3/4/5
Highest disclosed value: $3,377,033
7 rows are not safely comparable across share classes.
Quick read
Anna Berkenblit has the largest disclosed position value at $3.38M.
0 of 7 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 Anna Berkenblit's linked filing trail.
Disclosed position value
Top 5
Anna Berkenblit
$3.38M
Thomas Ryll
$2.51M
Kristen Harrington-Smith
$2.21M
Stacy Ann Coen
$1.38M
Mark J. Enyedy
$897.8K
Value bars compare disclosed positions; verify each figure against the linked filing evidence.
Detailed SEC evidence table Showing 1-7 of 7 holder rows
| Holder | Evidence | Ownership % | Position | 12M Net Δ | As of |
|---|---|---|---|---|---|
| Anna Berkenblit |
3/4/5
SVP & CHIEF MEDICAL OFFICER
|
—
class O/S missing
|
$3,377,033
113,935 shares
|
— | 30 Jun 2023 |
| Thomas Ryll |
3/4/5
SVP, Technical Operations
|
—
class O/S missing
|
$2,510,923
84,714 shares
|
— | 30 Jun 2021 |
| Kristen Harrington-Smith |
3/4/5
SVP & CHIEF COMMERCIAL OFFICER
|
—
mixed-class rows
|
$2,211,000
75,000 shares
mixed-class rows
|
— | 15 Nov 2022 |
| Stacy Ann Coen |
3/4/5
SVP & CHIEF BUSINESS OFFICER
|
— |
$1,383,800
|
— | 12 Feb 2024 |
| Mark J. Enyedy |
3/4/5
CHIEF EXECUTIVE OFFICER, Director
|
— |
$897,750
|
— | 12 Feb 2024 |
| Susan Altschuller |
3/4/5
SVP AND CFO
|
—
class O/S missing
|
$564,300
123,750 shares
|
— | 20 May 2022 |
| Renee Lentini |
3/4/5
VP & PRIN ACCTG OFFICER
|
— |
$245,469
|
— | 12 Feb 2024 |
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 13 Jul 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 1-20 of 20 reporting-owner rows connected to ImmunoGen, Inc.. Open a relationship link for the CIK-to-CIK filing trail.
Rows
20
Largest Forms 3/4/5 holder
Anna Berkenblit
Net 12M change
$0
Latest report
12 Feb 2024
Recent insider transactions for ImmunoGen, 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.