401(k) · DOL Form 5500 · 2024

2seventy Bio, Inc. 401(k) Plan

Data updated 2026-08-25

$32M
Total assets Below avg plan size
276
Participants Below avg headcount
78th
Percentile by assets National rank
$117,089
Avg per participant Below avg balance/head
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Official DOL plan name: 2seventy Bio, Inc. 401(k) Plan · Sponsored by 2seventy Bio, Inc. · Massachusetts · Professional & Technical Services

$32M in assets, 276 participants

2seventy Bio, Inc.'s 2seventy Bio, Inc. 401(k) Plan reported $32M in total assets and 276 participants in its 2024 DOL Form 5500 filing, ranking in the 78th 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.

  • #15,863 in Professional & Technical Services (20,173 peers)

Coverage in Massachusetts

2seventy Bio, Inc. 401(k) Plan covers 276 participants in Massachusetts, about 42% of the average Massachusetts filer (state average ~659 per filing). Assets: $32M.

#15,863
in Professional & Technical Services (20,173 peers)
-27.3%
assets change YoY
0.3×
vs typical plan assets (national mean)

The plan reported a net loss of $12M for the year, a single-year figure driven by markets and benefit payments, not a measure of plan health.

2seventy Bio, Inc. 401(k) Plan's outsized position by total assets

2seventy Bio, Inc. 401(k) Plan vs every filed plan by assets

End-of-year total assets · plan year 2024 · DOL Form 5500

$32,316,456 Top 22% higher than 78% of 123,620 filed plans

This plan $0 $2,050,000,000 every filed plan with reported assets, bucketed by value

Dashed line + filled bar = this entry, among filed plans.

Source U.S. Department of Labor Form 5500 filings (EBSA) · plan year 2024

2seventy Bio, Inc. 401(k) Plan among mid-size filed plans by headcount

Plan-year 2024 Form 5500 filings with a reported participant count, partitioned by headcount band, not by assets. 2seventy Bio, Inc. 401(k) Plan sits mid-pack in the medium band (276 participants).

What changed between DOL Form 5500 filings

plan year 2023 → plan year 2024

  • 2seventy Bio, Inc. 401(k) Plan reported net income fell from $14M in the plan year 2023 filing to -$12M in the plan year 2024 filing.
  • 2seventy Bio, Inc. 401(k) Plan reported participants fell from 413 in the plan year 2023 filing to 276 in the plan year 2024 filing.
  • 2seventy Bio, Inc. 401(k) Plan end-of-year assets fell from $44M in the plan year 2023 filing to $32M in the plan year 2024 filing.

See the national 2023→2024 release diff →

Form 5500 schedule snapshot

Filing strip 863658454 · 2seventy Bio, Inc. PY 2024 · 401(k)

2seventy Bio, Inc. 401(k) Plan · $32M · 276 · 78th

  • NET $32M
  • BOOK 276
  • VS-ST 78th
  • BOY 401(k)
  • SCH near R&h Construction Co. 401(k) Profit Sharing Retirement Plan
  • EBSA ind #15863

Stamps derive from this plan's Form 5500 line items (assets, participants, type, EIN, cohort placement) - not a quality rating of the sponsor. Read with Professional & Technical Services retirement plans → · Plans in Massachusetts →

2seventy Bio, Inc. 401(k) Plan in the asset neighbourhood

2seventy Bio, Inc. 401(k) Plan2seventy Bio, Inc. 401(k) Pl…$32MR&h Construction Co. 401(k) Profit Sharing Retirement PlanR&h Construction Co. 401(k) …$32MTwist Bioscience Corporation 401(k) PlanTwist Bioscience Corporation…$32MThe Bank of East Asia, Limited Savings PlanThe Bank of East Asia, Limit…$32MTexas Riogrande Legal Aid, Inc. 401(k) Profit Sharing PlanTexas Riogrande Legal Aid, I…$32M
End-of-year total assets ($M) among 2seventy Bio, Inc. 401(k) Plan and nearest nationwide 401(k) peers. Source: DOL Form 5500 plan year 2024.

Massachusetts filing particulars

Total Assets (Beginning of Year)$44M
Net Assets (End of Year)$32M
Net Income-$12M
Employer EIN863658454
Plan Effective Date2021-11-01
Filing StatusFILING RECEIVED

Sponsor Plan History (2seventy Bio, Inc.)

Sponsor-wide plan assets over time

All 2seventy Bio, Inc. plans reported in each filing year

Latest sponsor-wide plan assets
$32M 6.733421122832562% vs 2022
2024 filing year
$25M$30M$35M$40M$45M$50M 202220232024 $30.3M $32.3M ▲ +6.7%
Year Plans Participants Total Assets
2022 1 416 $30M
2023 1 413 $44M
2024 1 276 $32M

Nearby 401(k) Plans in Massachusetts

Peer 401(k) plans, same state, same plan type, ranked by total assets.

2seventy Bio, Inc. 401(k) Plan vs. nearby 401(k) plans in Massachusetts, assets vs. participants Scatter plot of 6 data points. -20000020000400006000080000 -10010203040 Total assets ($B) Participants 2seventy Bio, Inc. 401(k) Plan, Total assets ($B): 0.032316456 · Participants: 2762seventy Bio, Inc. 401(k) PlanFidelity Retirement Savings Plan, Total assets ($B): 34.201609937 · Participants: 66907Fidelity Retirement Savings PlanLiberty Mutual 401(k) Plan, Total assets ($B): 11.352606499 · Participants: 34618Liberty Mutual 401(k) PlanMassachusetts Institute of Technology Supplemental 401(k) Plan, Total assets ($B): 7.720373045 · Participants: 14762Massachusetts Institute of Technology Supplemental 401(k) PlanBoston Scientific Corporation 401(k) Retirement Savings Plan, Total assets ($B): 6.775289067 · Participants: 20639Boston Scientific Corporation 401(k) Retirement Savings PlanState Street Salary Savings Program, Total assets ($B): 6.532301643 · Participants: 12777State Street Salary Savings Program
2seventy Bio, Inc. 401(k) Plan vs. nearby 401(k) plans in Massachusetts, assets vs. participants
Compare 2seventy Bio, Inc. 401(k) Plan side-by-side with 3 peers →

2seventy Bio, Inc. 401(k) Plan's out-of-state 401(k) peers by assets and headcount

Outside Massachusetts, the nearest 401(k) by assets is R&h Construction Co. 401(k) Profit Sharing Retirement Plan in OR ($32M); by covered participants it is Fts International, LLC 401(k) Profit Sharing Plan in VA (276 participants). Same-state nearby plans are listed separately above.

Similar participant headcount

Nearest other-state filings by covered participants (276 participants); asset peers above are excluded.

DOL Form 5500 plan year 2024. Asset totals can differ widely at the same headcount; neither axis is a quality rating.

Frequently Asked Questions

How did 2seventy Bio, Inc. 401(k) Plan assets move in 2024? ▼
2seventy Bio, Inc. 401(k) Plan declined sharply - down 27.3% during 2024, from $44M to $32M. Reported net income was -$12M.
How have 2seventy Bio, Inc. plan assets changed over time? ▼
Across 3 plan years on file (2022-2024), 2seventy Bio, Inc.'s sponsor-wide assets grew 6.7%, from $30M to $32M.
Where does 2seventy Bio, Inc. 401(k) Plan rank by assets among Form 5500 filers? ▼
2seventy Bio, Inc. 401(k) Plan ranks in the 78th percentile by end-of-year assets among 123,622 plans that reported assets for plan year 2024 (in the top quartile of all filed plans by assets).
Which 401(k) plans are similar in size to 2seventy Bio, Inc. 401(k) Plan? ▼
Among 401(k) plans in other states, the closest by assets is R&h Construction Co. 401(k) Profit Sharing Retirement Plan in OR ($32M, 188 participants).
Which 401(k) plans cover a similar participant headcount to 2seventy Bio, Inc. 401(k) Plan? ▼
Among 401(k) plans in other states, the closest by covered participants is Fts International, LLC 401(k) Profit Sharing Plan in VA (276 participants, $101M in assets).

Source: U.S. Department of Labor, Employee Benefits Security Administration (EBSA), Form 5500 public disclosure dataset. Plan year 2024.

Source: DOL EFAST2 filing system (efast.dol.gov) - original filing retrieval by EIN 863658454.

Read our methodology - how this data is sourced, computed, and verified.

Data sourced from U.S. Department of Labor Form 5500 filings (EBSA). See our methodology for details.