The former OpenAI researcher’s fund was forced to unwind public equities after leveraged public bets plummeted. But he still has cards to play.

Situational Awareness, a hedge fund formed by former OpenAI researcher Leopold Aschenbrenner, has sold the majority of its public stock portfolio to Ken Griffin’s Citadel following steep losses over the past month, The Wall Street Journal reported earlier on Thursday. It’s a big comedown for the rising star who has been described as both “scarily smart,” and “brash.” German-born Aschenbrenner, who is 25, had no prior trading experience before launching the fund in 2024. He gained prominence for his investment thesis after publishing essays arguing that scaling AI would require a major build-up in semiconductors, compute, memory, and energy infrastructure. He joined OpenAI’s “superalignment” team in 2023, two years after graduating as valedictorian from Columbia at 19 (he enrolled at age 15). But he was dismissed from the company a year later over what it described as an improper disclosure of internal information. At the time, that team was led by OpenAI co-founder Ilya Sutskever and AI researcher Jan Leike. Soon after, Sutskever left to start his own company, Leike joined rival Anthropic, and Aschenbrenner launched his fund. Things couldn’t have been going better for Situational Awareness until very recently. The fund returned 439% for the year through June, Financial Times reported. Assets under management reportedly grew to as much as $45 billion during their peak before the fund’s positions began dropping sharply amid a broader decline in AI infrastructure investments, CNBC reported. Even after losses mounted, Aschenbrenner didn’t flinch. In a July 24 letter to investors seen by FT, he called the selloff one of the best buying opportunities since early last year and invited clients to commit fresh capital starting August 1. According to Bloomberg, the appeal didn’t garner the commitments he’d hoped would materialize. Some of the hardest-hit stocks held by the fund included memory chip producers SK Hynix and Sandisk, clean energy developer Bloom Energy, and neocloud provider Nebius Group, all of which have plummeted by more than 30% over the past month. AI infrastructure equities fell as public investors grew concerned that massive capital expenditures weren’t translating into near-term revenue. The fund’s losses were amplified by leverage, a common hedge fund strategy of using borrowed money to buy stocks. After Citadel bought the bulk of those holdings, Situational Awareness’ overall assets fell to roughly $10 billion, Bloomberg reported, down from around $20 billion in recent months, per an earlier WSJ report. Situational Awareness raised several hundred million dollars at its outset. Early backers of the fund include quant-trading firm Jane Street, Stripe co-founders Patrick and John Collison, and Meta executives Daniel Gross and Nat Friedman.