Aschenbrenner's Situational Awareness sells AI book to Citadel

A hedge fund built explicitly around the thesis that AI is underrated just got liquidated by that same trade, and the mechanics are worth reading carefully because they land on every other concentrated AI book on the Street. Situational Awareness, the fund launched by former OpenAI researcher Leopold Aschenbrenner, reportedly sold its entire book of public stock positions to Ken Griffin's Citadel in a single block trade, after leveraged AI bets and shorts against software names moved against it within weeks. CNBC first reported that the fund had been working with prime brokers including Bank of America, Goldman Sachs and JPMorgan Chase to meet margin calls and wind down positions in an orderly way.

The scale is what makes the story more than a personality piece. The fund had reportedly grown to as much as $45 billion after posting a 439% net return through the end of June 2026, built on concentrated long positions in AI hardware names such as SK Hynix, CoreWeave, Nebius, Micron and Bloom Energy, and short positions against software companies including Adobe. In July those infrastructure names fell somewhere between 35% and 47%, according to Bloomberg's coverage, while the software shorts rallied against the fund at the same time. With reported leverage around 4x across the book, that combination turned a drawdown into a forced liquidation rather than a paper loss.

Why this matters beyond one fund: this is the first high-profile blowup of a hedge fund constructed around the explicit AI-is-underrated thesis, and it happens during an AI-stock selloff that other concentrated funds are still living through. The prime brokers who wrote this leverage are the same ones extending margin to other AI-heavy books, and how they behave over the next few weeks will shape how quietly the broader AI trade gets de-risked before any next leg down.

Several pieces of this account are soft: the reporting is single-sourced in places and hedged with 'according to sources', the precise dollar loss to LPs is not disclosed, and Aschenbrenner has reportedly told investors he sees the rout as 'the most attractive investment opportunity since early 2025'. Still unreported: the LP-level damage, the price Citadel actually paid for the book, or whether other funds on the same primes are getting similar calls.

Situational Awareness itself is not going away — it will continue to operate as a private investment firm and still holds a roughly $5 billion stake in Anthropic, so a future Anthropic IPO could re-mark the story again. The near-term watch item is not Aschenbrenner. It is whether the primes now widen the same haircut treatment to every fund that spent 2026 running the same trade.