Venture Capital · Profile from Venture Capital Research Companion
Third Rock Ventures
The Boston biotech venture-creation firm that three former Millennium Pharmaceuticals executives founded in 2007. It builds disease-focused companies from scratch, staffs them with its own partners as interim executives, and produced a run of exits in the 2010s (Agios, Foundation Medicine, bluebird, Sage, Blueprint, Global Blood Therapeutics) that made it the main alternative to Flagship's platform-invention model.
At a glance
- Founded
- 2007, Boston, Massachusetts
- Founders
- Mark Levin (former founding CEO of Millennium Pharmaceuticals), Kevin Starr (former Millennium COO/CFO) and Robert (Bob) Tepper, MD (former Millennium president of R&D)
- Headquarters
- Boston, Massachusetts (Back Bay); a San Francisco office was opened in the 2010s (verify current status)
- Ownership / structure
- Private partnership managing closed-end venture funds (Third Rock Ventures I–VI). Partners combine investing with interim operating roles at portfolio companies
- Leadership (2026)
- Co-founder Bob Tepper remains a partner; Mark Levin and Kevin Starr have stepped back (reported as retired/founding partners). Other partners include Abbie Celniker, Reid Huber, Jeffrey Tong and Jigar Raythatha (promoted to partner in January 2024) (verify current roster and titles)
- AUM / capital raised
- ~$3.8bn raised across six funds as of the June 2022 close of the $1.1bn Fund VI (firm-reported)
- Stage focus
- Company creation and Series A, with follow-on capital through crossover and IPO. Focus is therapeutics, plus some diagnostics and tools (Foundation Medicine, Thrive)
- Signature investments
- Agios, Foundation Medicine, bluebird bio, Sage Therapeutics, Blueprint Medicines, Global Blood Therapeutics, Editas Medicine, Relay Therapeutics, Thrive Earlier Detection, Constellation, Voyager, Revolution Medicines (co-founded 2014, verify), Tango. Instructive failures: Neon Therapeutics, Goldfinch Bio (shut 2023), Jounce Therapeutics (sold 2023), bluebird's later collapse (sold to Carlyle/SK Capital in 2025)
10 deals and moves analysed
Each one gets a full strategy file in the companion: context, the decision, the financing, what happened, and the lesson.
2008
Agios Pharmaceuticals
Company Creation / Series A
2010
Foundation Medicine
Company Creation / Series A
2010
Sage Therapeutics
Company Creation / Series A
2010
bluebird bio
Series B Recapitalisation
2011
Blueprint Medicines
Company Creation / Series A
2011
Global Blood Therapeutics
Company Creation / Series A
2013
Editas Medicine
Company Creation / Series A
2015
Neon Therapeutics
Company Creation / Series A
2016
Relay Therapeutics
Company Creation / Series A
2019
Thrive Earlier Detection
Company Creation / Series A