Sean O Brien

Portfolio Co Investors 2026 for Sean O Brien: investors, rounds, and co-investor patterns from StartupFundraising.com research, updated for 2026.

Sean O Brien covers 30 companies with a founder-verified check from Sean O Brien, concentrated in Biotech, Climate, AI Infrastructure. Round sizes are not disclosed for these companies, so this report lists the verified positions rather than dollar totals.

Sean O Brien — verified positions

Sean O'Brien — related firms and companies (56)

Sean O'Brien profile · All research reports

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•By Alejandro Cremades