Leopold Aschenbrenner built one of the most talked-about hedge funds in recent memory. Then the margin calls came.
Citadel has acquired approximately $16 billion in public equity holdings from Situational Awareness LP, the AI-focused fund Aschenbrenner launched after leaving OpenAI in 2024. The fire sale was triggered by margin calls from Bank of America, Goldman Sachs, and JPMorgan, which demanded additional collateral as the fund’s positions deteriorated rapidly during late July.
From $45 billion to forced seller
Situational Awareness LP peaked at roughly $45 billion in assets under management earlier in 2026, making Aschenbrenner one of the most successful new fund managers in a generation. By late July, he was liquidating the majority of his public portfolio to keep the lights on.
The damage came from both sides of the book. Long positions in semiconductor companies like SK Hynix and Micron got hammered as AI infrastructure stocks sold off. Meanwhile, short positions in software stocks moved against the fund.
