Immunogen Inc.
Plan context: Immunogen Inc. 401(K) Plan and Trust
EIN 04-2726691 • Waltham, MA • 44 filings • 8 plans
Current Snapshot
Latest Year
2025
2025 Participants
233
2025 Assets
$81,802,294
2025 Contributions
$10,024,631
Historical Graphs
Total Assets Over Time
Aggregate end-of-year assets by filing year, excluding zero-asset years
Participants Over Time
Largest reported end-of-year plan headcount by filing year, used to avoid double-counting participants across overlapping plans
Company Timeline
Year summaries and individual filings are combined here so you can stay in one place while moving across years and plan filings.
| Year / Filing | Filings | Participants | Assets | Contributions | Contrib./Participant |
|---|---|---|---|---|---|
| 2025 | 3 | 0 | $0 | $0 | - |
| Immunogen Inc. 401(K) Plan and Trust | - | 0 | - | - | - |
| Immunogen Inc. Severance Pay Plan for All Employees | - | 0 | - | - | - |
| Immunogen Inc. Welfare Benefit Plan | - | 0 | - | - | - |
| 2024 | 3 | 233 | $81,802,294 | $10,024,631 | $43,024iApproximate average salary by contribution assumption: employee only about $1,075,604 at 4% or $717,069 at 6%; with 50% employer match about $717,069 at 4% or $478,046 at 6%; with 100% employer match about $537,802 at 4% or $358,535 at 6%. |
| Immunogen Inc. 401(K) Plan and Trust | - | 225 | $81,802,294 | $10,024,631 | $44,554iApproximate average salary by contribution assumption: employee only about $1,113,848 at 4% or $742,565 at 6%; with 50% employer match about $742,565 at 4% or $495,044 at 6%; with 100% employer match about $556,924 at 4% or $371,283 at 6%. |
| Immunogen Inc. Welfare Benefit Plan | - | 233 | - | - | - |
| Immunogen Inc. Severance Pay Plan for All Employees | - | 233 | - | - | - |
| 2023 | 3 | 295 | $73,333,902 | $9,273,337 | $31,435iApproximate average salary by contribution assumption: employee only about $785,876 at 4% or $523,917 at 6%; with 50% employer match about $523,917 at 4% or $349,278 at 6%; with 100% employer match about $392,938 at 4% or $261,959 at 6%. |
| Immunogen Inc. 401(K) Plan and Trust | - | 295 | $73,333,902 | $9,273,337 | $31,435iApproximate average salary by contribution assumption: employee only about $785,876 at 4% or $523,917 at 6%; with 50% employer match about $523,917 at 4% or $349,278 at 6%; with 100% employer match about $392,938 at 4% or $261,959 at 6%. |
| Immunogen Inc. Welfare Benefit Plan | - | 282 | - | - | - |
| Immunogen Inc. Severance Pay Plan for All Employees | - | 295 | - | - | - |
| 2022 | 3 | 277 | $58,490,751 | $7,534,765 | $27,201iApproximate average salary by contribution assumption: employee only about $680,033 at 4% or $453,355 at 6%; with 50% employer match about $453,355 at 4% or $302,237 at 6%; with 100% employer match about $340,016 at 4% or $226,678 at 6%. |
| Immunogen Inc. 401(K) Plan and Trust | - | 276 | $58,490,751 | $7,534,765 | $27,300iApproximate average salary by contribution assumption: employee only about $682,497 at 4% or $454,998 at 6%; with 50% employer match about $454,998 at 4% or $303,332 at 6%; with 100% employer match about $341,248 at 4% or $227,499 at 6%. |
| Immunogen Inc. Severance Pay Plan for All Employees | - | 277 | - | - | - |
| Immunogen Inc. Welfare Benefit Plan | - | 259 | - | - | - |
| 2021 | 1 | 106 | $66,996,309 | $2,428,573 | $22,911iApproximate average salary by contribution assumption: employee only about $572,777 at 4% or $381,851 at 6%; with 50% employer match about $381,851 at 4% or $254,567 at 6%; with 100% employer match about $286,388 at 4% or $190,926 at 6%. |
| Immunogen Inc. 401(K) Plan and Trust | - | 106 | $66,996,309 | $2,428,573 | $22,911iApproximate average salary by contribution assumption: employee only about $572,777 at 4% or $381,851 at 6%; with 50% employer match about $381,851 at 4% or $254,567 at 6%; with 100% employer match about $286,388 at 4% or $190,926 at 6%. |
| 2020 | 2 | 80 | $60,967,201 | $1,955,105 | $24,439iApproximate average salary by contribution assumption: employee only about $610,970 at 4% or $407,314 at 6%; with 50% employer match about $407,314 at 4% or $271,542 at 6%; with 100% employer match about $305,485 at 4% or $203,657 at 6%. |
| Immunogen Inc. 401(K) Plan and Trust | - | 79 | $60,967,201 | $1,955,105 | $24,748iApproximate average salary by contribution assumption: employee only about $618,704 at 4% or $412,469 at 6%; with 50% employer match about $412,469 at 4% or $274,980 at 6%; with 100% employer match about $309,352 at 4% or $206,235 at 6%. |
| Immunogen Inc. Welfare Benefit Plan | - | 80 | - | - | - |
| 2019 | 3 | 76 | $56,537,605 | $4,393,490 | $57,809iApproximate average salary by contribution assumption: employee only about $1,445,227 at 4% or $963,485 at 6%; with 50% employer match about $963,485 at 4% or $642,323 at 6%; with 100% employer match about $722,613 at 4% or $481,742 at 6%. |
| Immunogen Inc. 401(K) Plan and Trust | - | 74 | $56,537,605 | $4,393,490 | $59,371iApproximate average salary by contribution assumption: employee only about $1,484,287 at 4% or $989,525 at 6%; with 50% employer match about $989,525 at 4% or $659,683 at 6%; with 100% employer match about $742,144 at 4% or $494,762 at 6%. |
| Immunogen Inc. Welfare Benefit Plan | - | 75 | - | - | - |
| Immunogen Inc. Severance Pay Plan for All Employees | - | 76 | - | - | - |
| 2018 | 3 | 295 | $50,297,971 | $5,409,691 | $18,338iApproximate average salary by contribution assumption: employee only about $458,448 at 4% or $305,632 at 6%; with 50% employer match about $305,632 at 4% or $203,755 at 6%; with 100% employer match about $229,224 at 4% or $152,816 at 6%. |
| Immunogen Inc. 401(K) Plan and Trust | - | 295 | $50,297,971 | $5,409,691 | $18,338iApproximate average salary by contribution assumption: employee only about $458,448 at 4% or $305,632 at 6%; with 50% employer match about $305,632 at 4% or $203,755 at 6%; with 100% employer match about $229,224 at 4% or $152,816 at 6%. |
| Immunogen Inc. Welfare Benefit Plan | - | 295 | - | - | - |
| Immunogen Inc. Severance Pay Plan for All Employees | - | 295 | - | - | - |
| 2017 | 3 | 293 | $51,804,204 | $5,315,572 | $18,142iApproximate average salary by contribution assumption: employee only about $453,547 at 4% or $302,365 at 6%; with 50% employer match about $302,365 at 4% or $201,576 at 6%; with 100% employer match about $226,774 at 4% or $151,182 at 6%. |
| Immunogen Inc. 401(K) Plan and Trust | - | 293 | $51,804,204 | $5,315,572 | $18,142iApproximate average salary by contribution assumption: employee only about $453,547 at 4% or $302,365 at 6%; with 50% employer match about $302,365 at 4% or $201,576 at 6%; with 100% employer match about $226,774 at 4% or $151,182 at 6%. |
| Immunogen Inc. Welfare Benefit Plan | - | 292 | - | - | - |
| Immunogen Inc. Severance Pay Plan for All Employees | - | 292 | - | - | - |
| 2016 | 3 | 312 | $44,106,458 | $5,689,530 | $18,236iApproximate average salary by contribution assumption: employee only about $455,892 at 4% or $303,928 at 6%; with 50% employer match about $303,928 at 4% or $202,619 at 6%; with 100% employer match about $227,946 at 4% or $151,964 at 6%. |
| Immunogen Inc. 401(K) Plan and Trust | - | 312 | $44,106,458 | $5,689,530 | $18,236iApproximate average salary by contribution assumption: employee only about $455,892 at 4% or $303,928 at 6%; with 50% employer match about $303,928 at 4% or $202,619 at 6%; with 100% employer match about $227,946 at 4% or $151,964 at 6%. |
| Immunogen Inc. Welfare Benefit Plan | - | 304 | - | - | - |
| Immunogen Inc. Severance Pay Plan for All Employees | - | 295 | - | - | - |
| 2015 | 2 | 345 | $39,427,576 | $4,729,210 | $13,708iApproximate average salary by contribution assumption: employee only about $342,696 at 4% or $228,464 at 6%; with 50% employer match about $228,464 at 4% or $152,310 at 6%; with 100% employer match about $171,348 at 4% or $114,232 at 6%. |
| Immunogen Inc. 401(K) Plan and Trust | - | 345 | $39,427,576 | $4,729,210 | $13,708iApproximate average salary by contribution assumption: employee only about $342,696 at 4% or $228,464 at 6%; with 50% employer match about $228,464 at 4% or $152,310 at 6%; with 100% employer match about $171,348 at 4% or $114,232 at 6%. |
| Immunogen Inc. Welfare Benefit Plan | - | 345 | - | - | - |
| 2014 | 1 | 303 | $0 | $0 | - |
| Immunogen Inc. Welfare Benefit Plan | - | 303 | - | - | - |
| 2013 | 1 | 294 | $0 | $0 | - |
| Immunogen Inc. Welfare Benefit Plan | - | 294 | - | - | - |
| 2012 | 1 | 263 | $0 | $0 | - |
| Immunogen Inc. Welfare Benefit Plan | - | 263 | - | - | - |
| 2011 | 1 | 246 | $0 | $0 | - |
| Immunogen Inc. Welfare Benefit Plan | - | 246 | - | - | - |
| 2010 | 1 | 241 | $0 | $0 | - |
| Immunogen Inc. Welfare Benefit Plan | - | 241 | - | - | - |
| 2009 | 1 | 194 | $0 | $0 | - |
| Immunogen Inc. Welfare Benefit Plan | - | 194 | - | - | - |
| 2008 | 1 | 200 | $0 | $0 | - |
| Immunogen Inc. Severance Pay Plan for All Employees | - | 200 | - | - | - |
| 2007 | 1 | 214 | $0 | $0 | - |
| Immunogen Inc. Welfare Benefit Plan | - | 214 | - | - | - |
| 2006 | 1 | 201 | $0 | $0 | - |
| Immunogen Inc. Welfare Benefit Plan | - | 201 | - | - | - |
| 2005 | 1 | 184 | $0 | $0 | - |
| Immunogen Inc. Welfare Benefit Plan | - | 184 | - | - | - |
| 2004 | 1 | 166 | $0 | $0 | - |
| Immunogen Inc. Welfare Benefit Plan | - | 166 | - | - | - |
| 2003 | 1 | 0 | $0 | $0 | - |
| Immunogen Inc. Welfare Benefit Plan | - | 0 | - | - | - |
| 2001 | 1 | 69 | $0 | $0 | - |
| Immunogen Inc. 401(K) Plan and Trust | - | 69 | - | - | - |
| 2000 | 1 | 61 | $3,113,894 | $359,496 | $5,893iApproximate average salary by contribution assumption: employee only about $147,334 at 4% or $98,223 at 6%; with 50% employer match about $98,223 at 4% or $65,482 at 6%; with 100% employer match about $73,667 at 4% or $49,111 at 6%. |
| Immunogen Inc. 401(K) Plan and Trust | - | 61 | $3,113,894 | $359,496 | $5,893iApproximate average salary by contribution assumption: employee only about $147,334 at 4% or $98,223 at 6%; with 50% employer match about $98,223 at 4% or $65,482 at 6%; with 100% employer match about $73,667 at 4% or $49,111 at 6%. |
| 1999 | 1 | 64 | $3,315,514 | $330,374 | $5,162iApproximate average salary by contribution assumption: employee only about $129,052 at 4% or $86,035 at 6%; with 50% employer match about $86,035 at 4% or $57,357 at 6%; with 100% employer match about $64,526 at 4% or $43,017 at 6%. |
| Immunogen Inc. 401(K) Plan and Trust | - | 64 | $3,315,514 | $330,374 | $5,162iApproximate average salary by contribution assumption: employee only about $129,052 at 4% or $86,035 at 6%; with 50% employer match about $86,035 at 4% or $57,357 at 6%; with 100% employer match about $64,526 at 4% or $43,017 at 6%. |