Citadel Sheds 80% of Situational Awareness Portfolio Through $4 Billion in Block Trades

Ken Griffin told Citadel investors Friday that his firm has unwound more than 80% of the risk it took on when it bought the collapsed equity portfolio of Leopold Aschenbrenner's Situational Awareness hedge fund. The disclosure, in a letter to clients seen by Reuters, closes most of the chapter on one of the summer's more consequential forced-sale events.

The unwind was not quiet. According to the Reuters letter review, Citadel completed nearly 100 block trades totaling more than $4 billion in market value to trim the exposure. Griffin said the effort produced the largest single-session intraday block trades of the year in 10 separate names, a detail that gives traders a rough map of how concentrated the original book was.

Citadel entered talks to buy Situational Awareness assets on July 29, according to the letter as reported by CNBC. The next day, CNBC's David Faber reported that the fund had been forced to liquidate its entire public equities book after suffering steep losses. Citadel's role as the buyer was confirmed shortly after. According to Reuters, Citadel bought the positions at a discount of more than 10%, a price that helped stabilize the market on the last two trading days of July.

The arithmetic behind the Situational Awareness blowup is stark. The fund had concentrated its longs in companies it saw as direct beneficiaries of physical AI infrastructure build-out. Sandisk and Bloom Energy, two of the larger disclosed stakes, each fell more than 50% during June and July. At the same time, the fund held short positions in software names on the thesis that AI would erode those businesses. That thesis inverted: Adobe and peers recovered, meaning the fund was losing on both sides of the book simultaneously. The double-sided loss triggered margin calls and compulsory sales.

The fund, run by a former OpenAI researcher who launched it at 25 in July 2024, had managed roughly $16 billion in public equities before the forced unwind. According to Reuters, the portfolio lost 67% of its value in July alone.

Citadel, which manages about $77 billion in assets under management, declined to comment beyond the letter. Griffin's flagship Wellington multi-strategy fund gained 5.94% in July and stood up 12% for the year through that month, according to Reuters, meaning the firm entered the Situational Awareness rescue from a position of strength rather than desperation.

Griffin's characterization of the trade in the Friday letter is worth reading with the skepticism any forward-positioned quote deserves. He framed the rapid distribution of risk as proof of execution capability, writing that the ability to move the positions was central to the firm's investment thesis from the start. That may be true. It is also the kind of language that sounds better after the trades clear at a profit than before.

What the episode does confirm is structural: a large, thematically concentrated hedge fund with a leveraged long-short book can unravel fast when the spread between its long and short baskets moves the wrong way for even two months. The banks that handled prime brokerage for both Citadel and Situational Awareness absorbed real execution risk to get the transfer done. Griffin acknowledged that directly, crediting the prime brokerage teams in his letter as reported by Reuters. That's an unusual public nod to counterparty infrastructure, and it signals that the logistics of the transfer were more complex than a standard block-trade sequence.

Sources cited:
- Reuters (via WKZO/WTAQ wire pickups) (https://wkzo.com/2026/08/21/citadel-sheds-over-80-of-aggregate-risk-from-situational-awareness-portfolio/)
- CNBC (https://www.cnbc.com/2026/08/21/citadel-situational-awareness-ken-griffin.html)
- Bloomberg (https://www.bloomberg.com/news/articles/2026-08-21/citadel-sold-more-than-4-billion-of-situational-awareness-bets)