The AI fund that blew up in July took one of the world's best trading firms down $15 billion with it
Reuters reported on 14 August, citing people familiar with the matter, that Jane Street lost about $15 billion in July, and that its exposure to Situational Awareness — the AI-focused fund run by former OpenAI researcher Leopold Aschenbrenner — was a large part of it. Situational fell from a $45 billion peak to roughly $10 billion inside a single month; margin calls forced it to dump most of its stock portfolio in a fire sale to Ken Griffin's Citadel. Bloomberg reported the same $15 billion figure the same day. Jane Street is not in trouble: it has booked more than $40 billion in trading revenue so far this year, and executives told staff only that July was a bad month.
Why it mattersUntil now the AI trade going wrong looked like a problem for the people who made the bet. This is the first hard number showing it travelling somewhere else — into a firm that does not pick AI winners for a living and handles a meaningful share of daily volume in US stocks and ETFs. One fund's conviction became one trading giant's worst month, and $15 billion is large even against $40 billion of revenue. The question the rest of Wall Street is now asking is not whether Aschenbrenner was wrong, but how many other balance sheets were quietly standing behind that position.
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