Third Rock Ventures
Boston, Massachusetts, United StatesFounded 2007
Third Rock Ventures is a leading healthcare venture capital firm focused on advancing disruptive areas of science and medicine to deliver breakthroughs to patients. Founded in 2007 and headquartered in Boston, the firm discovers, launches, and builds early-stage biotechnology and life sciences companies across small-molecule drugs, antibodies, proteins, and cell and gene therapies. Its latest fund, Fund VI, closed at $1.1 billion.
54% of their portfolio is in Biotech & Life Sciences. Deal activity increased 100% year-over-year (2 deals in the last 12 months). Average disclosed round size is $78.1M (across 62 rounds with reported amounts).
Portfolio
53
Fund Size
$1.1B
Top Stage
Series A
Last 12 Mo
2
Team
Portfolio Breakdown
Stage Distribution
Sector Distribution
Investment Activity
DealsAvg Round Size
Portfolio
68 investments
| Company | Round | Amount | Date |
|---|---|---|---|
 Merida Biosciences | Series A | $121M | Aug 2026 |
| TTerremoto Biosciences | Series C | $108M | Apr 2026 |
 ArtBio | Series B | $132M | Jul 2025 |
 Corvia Medical | Growth | $55M | Jun 2025 |
 Seaport Therapeutics | Series B | $225M | Oct 2024 |
 Maze Therapeutics | Unknown | $115M | Jan 2024 |
 Asher Bio | Series C | $55M | Jan 2024 |
| ArtBio | Series A | $90M | Dec 2023 |
 Flare Therapeutics | Series B | $123M | Mar 2023 |
 Cargo Therapeutics | Series A | $200M | Mar 2023 |
| TTerremoto Biosciences | Series B | $175M | Jan 2023 |
 Rapport Therapeutics, Inc. | Series B | $150M | Jan 2023 |
 Septerna | Series B | — | Jan 2023 |
 MOMA Therapeutics | Series B | $150M | May 2022 |
 Celsius Therapeutics | Series B | $83M | Mar 2022 |
| Celsius Therapeutics | Series A | $63M | Mar 2022 |
| Merida Biosciences | Seed | — | Jan 2022 |
| Asher Bio | Series B | $108M | Sep 2021 |
| AAbata Therapeutics | Unknown | $95M | Jan 2021 |
| TThrive Earlier Detection | Series A | $110M | May 2019 |
 Pliant Therapeutics | Series B | $62M | Jul 2018 |
 Decibel Therapeutics | Series C | $55M | Jun 2018 |
| Celsius Therapeutics | Series A | $65M | Jan 2018 |
| MMagenta Therapeutics | Series B | $50M | May 2017 |
 Neon Therapeutics | Series B | $36M | Jan 2017 |
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Top Co-Investors
Casdin Capital16 shared
Cormorant Asset Management12 shared
GV9 shared
Wellington Management8 shared
RA Capital Management8 shared
Foresite Capital8 shared
Alexandria Venture Investments7 shared
The Invus Group, LLC7 shared
Alphabet Inc.7 shared
Bessemer Venture Partners5 shared
Omega Funds5 shared
Sofinnova Partners5 shared
Eventide Asset Management5 shared
Nextech Invest Ltd.5 shared
Pfizer Ventures5 shared
Redmile Group5 shared
Logos Capital5 shared
ARCH Venture Partners5 shared
The Column Group5 shared
Bain Capital Life Sciences5 shared
Last updated: 7 September 2026