2seventy Bio, Inc. 401(k) Plan

401(k) · DOL Form 5500 · 2024

What the Filing Says About 2seventy Bio, Inc. 401(k) Plan

2seventy Bio, Inc. 401(k) Plan is a 401(k) retirement plan sponsored by 2seventy Bio, Inc., headquartered in Massachusetts. According to the U.S. Department of Labor's 2024 Form 5500 filing, the plan reports $32M in total end-of-year assets and covers 276 participants across the Professional & Technical Services industry. The sponsor's EIN on file with the U.S. Department of Labor is 863658454, and the plan has been effective since 2021-11-01. Its filing status is currently FILING RECEIVED.

Year over year, total assets declined sharply from $44M at the beginning of 2024 to $32M at year-end - down 27.3%. Net assets (after liabilities) closed the year at $32M, with reported net income of -$12M driven by investment returns, contributions received, and benefit payments during the period. These figures reflect what the plan administrator certified on Schedule H or Schedule I of the Form 5500 annual return and can be compared against 2 prior plan-year filings from the same sponsor shown below.

Across the 3 plan years 2seventy Bio, Inc. has on file with PlainRetire (2022-2024), sponsor-wide plan assets have moved from $30M to $32M, a gain of 6.7%, while reported participants moved from 416 to 276 (-33.7%). The strongest year on file by total sponsor assets was 2023 at $44M; the softest was 2022 at $30M. Year-by-year, sponsor-wide filings show: 2022 - $30M in assets across 1 plan covering 416 participants; 2023 - $44M in assets across 1 plan covering 413 participants; 2024 - $32M in assets across 1 plan covering 276 participants.

By assets, 2seventy Bio, Inc. 401(k) Plan outranks 78% of the 116,472 plans that filed a Form 5500 for the 2024 plan year, and holds roughly 0.3x the national average plan size of $100M and 730 average participants.

Asset totals and participant counts reflect a single plan year snapshot and can change materially with market conditions, plan mergers, or workforce changes. Fields such as "net income" include both realized investment performance and contribution/distribution flows, a single-year figure does not by itself indicate plan health or participant outcomes. This page summarizes public DOL disclosures for research and educational purposes only and is not retirement, tax, legal, or financial advice. Before making decisions about your own retirement benefits or evaluating an employer's plan, verify the underlying filing directly via the DOL EFAST2 system and consult a qualified professional.

How the percentile is calculated: we count every plan that filed a 2024 Form 5500 with a reported end-of-year asset figure (116,472 plans), rank 2seventy Bio, Inc. 401(k) Plan against all of them by total assets, and report the share of those plans it outranks. A plan reporting no asset figure for the year is excluded from the ranking rather than assumed to be zero.