401(k) · DOL Form 5500 · 2024
Biogen Inc. 401(k) Plan
Data updated 2026-08-11
- $2.2B
- Total assets
- 4,292
- Participants
- 99th
- Percentile by assets
- $503,073
- Avg per participant
Official DOL plan name: Biogen 401(k) Savings Plan · Sponsored by Biogen Inc. · Massachusetts · Manufacturing
$2.2B in assets, 4,292 participants
Biogen Inc.'s Biogen 401(k) Savings Plan reported $2.2B in total assets and 4,292 participants in its 2024 DOL Form 5500 filing, ranking in the 99th percentile by assets among filed plans. Figures are as reported by the plan sponsor to the Department of Labor, not audited or endorsed by PlainRetire.
- 99th percentile by assets (of 123,622 plans)
- #17,547 in Manufacturing (17,777 peers)
Coverage in Massachusetts
Biogen 401(k) Savings Plan covers 4,292 participants in Massachusetts, 6.5x the typical Massachusetts plan (state average ~659 per filing). Assets: $2.2B.
- $2.2B
- total plan assets (2024 EOY)
- 4,292
- covered participants
- 99th
- percentile by assets (of 123,622 plans)
- $503,073
- avg assets per participant
What changed between DOL Form 5500 filings
plan year 2023 → plan year 2024
- Biogen 401(k) Savings Plan reported net income fell from $303M in the plan year 2023 filing to $221M in the plan year 2024 filing.
- Biogen 401(k) Savings Plan reported participants fell from 5,003 in the plan year 2023 filing to 4,292 in the plan year 2024 filing.
- Biogen 401(k) Savings Plan end-of-year assets rose from $1.9B in the plan year 2023 filing to $2.2B in the plan year 2024 filing.
Participants vs Massachusetts filers
In Massachusetts, the average filing covers about 659 participants across 4,265 plans. Biogen 401(k) Savings Plan reports 4,292 participants - 6.5x that state average ($2.2B EOY assets).
Massachusetts filing particulars
| Total Assets (Beginning of Year) | $1.9B |
|---|---|
| Net Assets (End of Year) | $2.2B |
| Net Income | $221M |
| Employer EIN | 330112644 |
| Plan Effective Date | 2004-01-06 |
| Filing Status | FILING RECEIVED |
Sponsor Plan History (Biogen Inc.)
| Year | Plans | Participants | Total Assets |
|---|---|---|---|
| 2022 | 1 | 5,611 | $1.6B |
| 2023 | 1 | 5,003 | $1.9B |
| 2024 | 1 | 4,292 | $2.2B |
Nearby 401(k) Plans in Massachusetts
Peer 401(k) plans, same state, same plan type, ranked by total assets.
Biogen 401(k) Savings Plan vs. nearby 401(k) plans in Massachusetts, assets vs. participants
- Fidelity Retirement Savings Plan $34.2B · 66,907
- Liberty Mutual 401(k) Plan $11.4B · 34,618
- Massachusetts Institute of Technology Supplemental 401(k) Plan $7.7B · 14,762
- Boston Scientific Corporation 401(k) Retirement Savings Plan $6.8B · 20,639
- State Street Salary Savings Program $6.5B · 12,777
Similar-Sized 401(k) Plans Nationally
401(k) plans in other states closest to Biogen 401(k) Savings Plan by total assets, not by location.
- Tetra Tech, Inc. and Subsidiaries Retirement Plan (CT) $2.2B · 11,882
- Medamerica 401(k) Profit Sharing Plan for Employees of Vituity (CA) $2.2B · 5,429
- Allianz Asset Management of America 401(k) Savings and Retirement Plan (CA) $2.2B · 2,532
- Assurant 401(k) Plan (GA) $2.2B · 9,941
Frequently Asked Questions
How did Biogen 401(k) Savings Plan assets move in 2024? ▼
How have Biogen Inc. plan assets changed over time? ▼
Where does Biogen 401(k) Savings Plan rank by assets among Form 5500 filers? ▼
Which 401(k) plans are similar in size to Biogen 401(k) Savings Plan? ▼
Next read for Biogen 401(k) Savings Plan
Filing takeaways
Ways to act on Biogen 401(k) Savings Plan's numbers.
- By total assets, Biogen 401(k) Savings Plan ranks among the largest 1% of all filed plans. See the largest plans
- Compare it side-by-side against 3 similar 401(k) plans in Massachusetts. Compare plans
- Biogen Inc.'s sponsor-wide assets have grown 34.8% since 2022 across 3 plan years on file. More Manufacturing plans