Leopold Aschenbrenner's hedge fund, Situational Awareness, experienced a dramatic downturn in July 2026, losing 67% of its value after an initial gain of 439% in the first half of the year. The fund, which peaked at $45 billion in assets, leveraged its bets on AI-linked stocks by as much as four times, primarily investing in infrastructure providers and other AI-related companies. This high leverage intensified losses when AI stocks began to decline, triggering substantial margin calls from its prime brokers, including Goldman Sachs, JPMorgan, Citigroup, and Bank of America. The fund never missed a margin call, but faced severe liquidity constraints.
To meet these demands and manage the mounting losses, Situational Awareness sold the bulk of its $16 billion public equities portfolio to Citadel at approximately a 10% discount on July 30. This transaction helped the fund survive, preserving its remaining $10 billion portfolio, which includes a significant stake in Anthropic valued at about $5 billion. Following the sale, AI stocks rebounded, providing Citadel with a substantial windfall. Despite the significant upheaval, the fund remains up about 80% year-to-date.
The incident has drawn comparisons to the Archegos Capital Management collapse in 2021, though banks asserted they would have been fine even without Citadel's intervention. Prime brokers largely avoided losses due to improved risk management, dynamic margining practices, and additional protections, such as recourse to both public and private investments, including the Anthropic stake. Bank of America CEO Brian Moynihan acknowledged the situation as a "warning shot." The SEC has reportedly issued subpoenas to the involved banks to investigate the fund's trading activity, leverage use, and communications with lenders, though this does not imply wrongdoing.
Regulators are now scrutinizing bank lending standards, especially as prime brokerage borrowing from hedge funds has nearly doubled to $3.2 trillion over the past five years. While some banks had declined to finance Aschenbrenner due to his concentrated bets, high leverage, and inexperience, the general consensus among bankers is that the system worked as intended, with a "weak hand" transferring assets to a "strong hand" without systemic risk or losses to prime brokers. The episode serves as a reminder of the inherent risks in the prime brokerage business despite its high, steady returns.
