Ken Griffin

American hedge fund manager who founded Citadel at age 22 — building it into one of the world's largest and most successful hedge funds — and who started trading from his Harvard dorm room with a satellite dish to receive market data.

Built Citadel as the most successful multi-strategy hedge fund of its era — through rigorous quantitative analysis, systematic risk management, and an obsession with talent recruitment — while his early start (trading convertible bonds from his Harvard dorm room) became a canonical story of conviction and early action.