Massachusetts › Manufacturing › 5,000 to 24,999 participants
Form 5500 statement · plan year 1 Jan 2024 to 31 Dec 2024
Biogen 401(k) Savings Plan
Sponsored by Biogen Inc., Cambridge, MA
Form 5500 information is as filed by the plan administrator with the Department of Labor and may be amended. Figures reflect the plan year shown, not current balances. Form 5500 contains no individual account balances. Look up the original filing at EFAST2.
Biogen 401(k) Savings Plan is a 401(k) plan sponsored by Biogen Inc. of Cambridge, Massachusetts. For the plan year ending 31 Dec 2024 it reported 7,813 participants, 4,289 of them active, and net assets of $2.16B.
Net assets came to $276,359 per participant, well above the $64,499 median for defined contribution plans with 5,000 to 24,999 participants and well above the $62,303 median for defined contribution plans in manufacturing. The figure is an average across everyone in the plan, including former employees with small balances; Form 5500 holds no individual account data.
The employer contributed $46.2M during the year, or $10,760 per active participant against a same-size median of $2,424; participants contributed $70.7M and $16.5M arrived as rollovers and other contributions. Benefits paid out totalled $252M.
The filing reports no service provider compensation on Schedule C. That is common where fees are paid by the employer or taken from investment returns, neither of which appears there. Administrative expenses charged to the plan were −$405K.
Across the filings on record, net assets went from $355M in 2009 to $2.16B in 2024 (up 508%), and participants from 4,708 to 7,813 (up 66%).
The independent accountant's opinion on the financial statements was unmodified (unqualified), from an audit whose scope was limited under ERISA section 103(a)(3)(C) to exclude investment information certified by a bank or insurer.
Compared with similar plans
| Measure | This plan | Same size | Same industry | All US DC plans |
|---|---|---|---|---|
| Net assets per participant | $276,359 | $64,499 | $62,303 | $53,102 |
| Employer contributions per active participant | $10,760 | $2,424 | $2,187 | $2,175 |
| Schedule C compensation per participant | — | $53.38 | $136 | $123 |
| Schedule C compensation, share of net assets | — | 0.09% | 0.24% | 0.26% |
| Administrative expenses per participant | — | $54.85 | $131 | $116 |
Peer columns are medians for plan year 2024 across defined contribution plans with 100 or more participants: 5,000 to 24,999 participants (2,605 plans), manufacturing (11,377) and all US plans (63,460). Fee medians cover plans that report an amount.
Trend by plan year
| Plan year | Participants | Net assets | Per participant | Employer contributions | Participant contributions | Schedule C compensation |
|---|---|---|---|---|---|---|
| 2024 | 7,813 | $2.16B | $276,359 | $46.2M | $70.7M | $0 |
| 2023 | 8,088 | $1.94B | $239,625 | $51.7M | $79.0M | $0 |
| 2022 | 8,349 | $1.60B | $191,790 | $52.9M | $78.4M | $0 |
| 2021 | 8,420 | $2.01B | $238,610 | $54.8M | $80.2M | $0 |
| 2020 | 8,247 | $1.70B | $206,462 | $48.8M | $69.3M | $0 |
| 2019 | 7,255 | $1.35B | $185,523 | $41.8M | $58.7M | $0 |
| 2018 | 6,878 | $1.05B | $152,246 | $39.4M | $55.2M | $15K |
| 2017 | 6,674 | $1.11B | $166,039 | $38.8M | $53.0M | $10K |
| 2016 | 6,585 | $940M | $142,746 | $39.2M | $53.3M | $0 |
| 2015 | 6,632 | $873M | $131,627 | $44.5M | $60.6M | $0 |
| 2014 | 6,381 | $824M | $129,110 | $38.9M | $52.7M | $0 |
| 2013 | 5,937 | $716M | $120,520 | $34.8M | $46.0M | $0 |
| 2012 | 5,514 | $530M | $96,073 | $27.8M | $37.8M | $0 |
| 2011 | 4,920 | $440M | $89,396 | $23.9M | $32.9M | $6,000 |
| 2010 | 4,775 | $452M | $94,569 | $25.1M | $34.7M | $6,000 |
| 2009 | 4,708 | $355M | $75,418 | $23.4M | $31.9M | $7,000 |
Years in which the plan filed the full Form 5500 with 100 or more participants, from 2009. Plan year is the year in which the plan year began.
Statement for the year
- Net assets, beginning of year$1,938,085,017
- Employer contributions$46,151,108
- Participant contributions$70,668,367
- Rollovers and other contributions$16,541,765
- Total contributions$133,361,240
- Total income, including investment results$472,910,354
- Benefits paid$251,944,167
- Administrative expenses−$404,525
- Total expenses$251,804,788
- Net income$221,105,566
- Net transfers$0
- Net assets, end of year$2,159,190,583
Participants
- Active participants4,289
- Retired or separated, receiving benefits22
- Retired or separated, entitled to future benefits3,495
- Participants with account balances7,636
- Total participants, end of year7,813
Fees and service providers
| Organisation | Services reported | Direct | Indirect |
|---|---|---|---|
| Fidelity Investments Institutional | Participant loan processing | $0 | $0 |
Schedule C, Part I line 2: providers that received $5,000 or more, with the form's own service codes. Individuals named on Schedule C (plan employees, individual trustees) are never shown and their compensation is excluded. Eligible indirect compensation disclosed by formula carries no dollar amount. See how to read Schedule C fees.
Administrative expenses on Schedule H
- Contract administrator fees$2,700
- Total administrative expenses−$404,525
Investment structure
Assets at year end by Schedule H category. The form shows the kind of vehicle holding the money, not the funds on the menu.
- Common/collective trusts$1.86B · 86.0%
- Registered investment companies (mutual funds)$221M · 10.2%
- Cash (interest and non-interest bearing)$64.5M · 3.0%
- Participant loans$11.9M · 0.5%
- Receivables$5.4M · 0.3%
Audit and compliance answers, as filed
- Accountant's opinionUnmodified (unqualified)
- Audit scope limited under ERISA section 103(a)(3)(C)Yes
- Accounting firmPricewaterhouseCoopers
- Participant contributions reported as transmitted lateNo
- Covered by a fidelity bondYes, $10,000,000
- Blackout period during the yearNo
These are the plan administrator's own answers on Schedule H, Part IV. A reported late transmittal is the filer's disclosure of a timing lapse, usually corrected through the Department of Labor's voluntary program; the amount is the total involved, not a loss.
Plan characteristics
2AAge/service weighted or new comparability or similar plan2EProfit-sharing plan2FERISA section 404(c) plan2GTotal participant-directed account plan2JCode section 401(k) feature2KCode section 401(m) arrangement2TTotal or partial participant-directed account plan with a default investment account
Codes entered on Form 5500 line 8a, with the labels from the official instructions. Business code 325410: Pharmaceutical & Medicine Mfg.
Similar plans in Massachusetts
| Plan | Sponsor | Participants | Net assets | Per participant |
|---|---|---|---|---|
| Analog Devices, Inc. the Investment Partnership Plan | Analog Devices, Inc. | 11,411 | $4.34B | $380,042 |
| Hologic, Inc. Savings and Investment Plan | Hologic, Inc. | 6,876 | $1.19B | $172,433 |
| Philips North America 401(k) Plan | Philips North America LLC | 27,842 | $6.37B | $228,677 |
| Zoll Medical Corporation Employee Savings Plan | Zoll Medical Corporation | 6,809 | $782M | $114,850 |
| Boston Scientific Corporation 401(k) Retirement Savings Plan | Boston Scientific Corporation | 34,105 | $7.90B | $231,688 |
| Entegris, Inc. 401(k) Retirement Savings Plan | Entegris, Inc. | 6,446 | $881M | $136,645 |
Defined contribution plans in manufacturing closest in size.
Questions and answers
How big is Biogen 401(k) Savings Plan?
7,813 participants at the end of the plan year ending 31 Dec 2024, of whom 4,289 were active employees, with net assets of $2,159,190,583. Among defined contribution plans that places it in the 5,000 to 24,999 participants band, which held 2,605 plans in plan year 2024.
What does Biogen Inc. contribute per participant?
The filing reports $46,151,108 in employer contributions for the year, which is $10,760 per active participant; the median for plans of the same type and size was $2,424 in plan year 2024. Form 5500 reports the total only. It does not state the match formula, and the per-participant figure is an average, not any one person's contribution.
What fees does the plan pay and how do they compare?
Schedule C reports no provider compensation for the year. Administrative expenses on Schedule H were −$404,525. Investment costs deducted inside mutual funds and other pooled vehicles are not itemised on Form 5500, so these figures are a floor rather than a full cost.
Who runs the plan?
The sponsor is Biogen Inc.. Recordkeeping or administration: Fidelity Investments Institutional. The financial statements were audited by PricewaterhouseCoopers. Form 5500 also names the plan administrator's signer and other individuals; this site publishes organisations only.
Was the audit opinion unqualified?
The filing reports an unmodified (unqualified) opinion from a limited-scope audit, in which the accountant did not audit investment information certified by a bank or insurance company. Unmodified (formerly "unqualified") is the standard clean opinion.
How current is this, and does it show my balance?
This is the Form 5500 for the plan year 1 Jan 2024 to 31 Dec 2024, received by the Department of Labor on 14 Oct 2025. Filings are due seven months after the plan year ends, or nine and a half with an extension, so the public record always runs a year or more behind. It contains plan-level totals only: no individual balances, contributions or names of participants exist in the data.
Provenance
Source: U.S. Department of Labor, Employee Benefits Security Administration, Form 5500 research files (Form 5500, Schedule H, Schedule C) for plan years 2009 to 2025, public domain, with filings received through 24 Aug 2026. This page shows the latest filing on record for EIN 33-0112644, plan 001, received 14 Oct 2025; an amended filing replaces it at the next build. Medians and percentiles are computed by this site; see the methodology. Report an error through corrections.