Portfolio Co Investors 2026 for Third Rock Ventures: investors, rounds, and co-investor patterns from StartupFundraising.com research, updated for 2026.
Third Rock Ventures accounts for 40 tracked companies with verified cap-table data, 40 of which disclose round sizes totalling $8.9B. The median disclosed raise is $150M, and the largest is Revolution Medicines at $2.1B, ahead of Tubulis ($575M) and Candid Therapeutics ($370M).
The names that recur most often on these co-invested cap tables are Third Rock Ventures (40 companies), Casdin Capital (8 companies), GV (5 companies), Nextech Invest (5 companies), RA Capital Management (5 companies), Foresite Capital (4 companies). By latest disclosed round, the market skews Series A (16), Series B (9), Series C (8), IPO (3).
Companies tracked: 40
Disclosed funding total: $8.9B across 40 companies
Median disclosed raise: $150M
Largest raise: Revolution Medicines — $2.1B
Stage mix: Series A 16 · Series B 9 · Series C 8 · IPO 3
