Aschenbrenner's AI Fund Sells Stocks, Keeps Anthropic Stake

From $45 billion at its peak to roughly $10 billion today. That is the arc of Situational Awareness, the AI-focused hedge fund run by 25-year-old former OpenAI researcher Leopold Aschenbrenner, which sold most of its public stock portfolio to Ken Griffin's Citadel this week after a brutal July.

The mechanics were straightforward leverage math. The fund held borrowed-money positions in AI infrastructure names, among them SK Hynix, Sandisk, Bloom Energy, and Nebius Group, a basket that fell more than 30 percent in a month as investors began doubting whether enormous capital spending would show up in near-term revenue. Leverage turned a drawdown into a forced unwind, and Citadel absorbed the bulk of the positions. A margin call, in plain terms, is the lender demanding cash the moment your collateral shrinks; at this scale of borrowing, a 30 percent slide leaves no room to wait for a recovery.

A 439 percent year, then the floor gave way

Through June, the fund was up 439 percent for the year, one of the most spectacular runs in hedge fund history. Assets that peaked near $45 billion had already slid to about $20 billion in recent months before this week's sale cut them to roughly $10 billion. What survived the fire sale is telling: a $5 billion private stake in Anthropic, valued at $965 billion in its May Series H round, plus positions in chipmaker MatX and data-center startup Fluidstack.

One fund's stumble, or a market signal?

The episode also lands in a market already on edge: Asian chip stocks sold off hard earlier this month on the same capex doubts, and reporting has put the hidden AI-related debt of five US tech giants at $1.65 trillion. It is tempting to read this as the AI bubble popping, and just as tempting to dismiss it as one overleveraged fund. The truth sits in between. The same month that punished chip stocks punished anyone borrowing against uninterrupted AI growth, yet the fund's private bets, notably Anthropic, kept their value, and commentators summarizing the episode landed on a fair verdict: the thesis may still be right, but the leverage and the timing were not. For companies that buy AI rather than trade it, the takeaway is calm but real. Financing turbulence rarely changes what the technology can do, but it can change vendors' prices, roadmaps, and survival odds, so treat vendor diversity as risk management rather than indecision.

Sources: TechCrunch, The Decoder