Ken Griffin, Founder and Chief Executive Officer of Citadel, speaks during the America Business Forum at Kaseya Center in Miami, Florida, U.S. Nov. 5, 2025. Ken Griffin's Citadel posted strong gains across its major hedge funds in July, helped by a recovery in risk assets and a discounted purchase of assets from the collapse of Leopold Aschenbrenner's Situational Awareness hedge fund to end the month, according to a person familiar with the firm's performance. The tactical fund and equities fund both had their best month ever. Situational Awareness, founded by former OpenAI researcher Leopold Aschenbrenner, was forced to unwind many of its positions after a sharp reversal in artificial intelligence trades left it bleeding on both sides of its book. Several of the fund's prime brokers worked to reduce positions in an orderly fashion as Situational Awareness sought to meet margin requirements.