There must be no shortage of investors who have been bracing for the moment the tide would turn on the recent decline in AI infrastructure-related stocks. It was former OpenAI researcher Leopold Aschenbrenner—someone who warned earlier than almost anyone about the arrival of AI—who delivered an unexpected answer to that concern. It emerged on July 30, 2026, that the hedge fund he leads had racked up massive losses on its own long positions in AI stocks and sold the bulk of its public equity portfolio to Ken Griffin's Citadel. The fund's asset base shrank from $45 billion to roughly $10 billion in less than a month.
$45 Billion to $10 Billion: What Happened in the Block Sale to Citadel
According to a CNBC report on July 30, Situational Awareness LP (Limited Partnership), the hedge fund led by Aschenbrenner, sold the bulk of both its long and short public equity positions to Citadel in a single block trade. Bloomberg reported the same day that this sale brought the fund's assets under management down to roughly $10 billion.
The Kobeissi Letter, citing WSJ reporting, noted that this asset scale had reached $45 billion as recently as July 1—less than a month earlier. That works out to nearly 80% of the fund's assets vanishing in under a month. The Financial Times, meanwhile, reported independently that the public equity portfolio stood at $16 billion before the sale, with Citadel acquiring the majority of that amount. The acquisition price itself has not been disclosed. The $45 billion peak asset figure, the $10 billion post-sale remaining assets, and the $16 billion pre-sale public equity portfolio each refer to different metrics—total assets, remaining assets under management, and public equity holdings, respectively—and are not figures that can simply be added together or compared as straightforward multiples.
Private equity holdings were not part of this sale. Notably, the stake in Anthropic, worth an estimated $5 billion, remains untouched, and Situational Awareness LP reportedly plans to continue operating as a private investment firm. What was sold was strictly the fund's publicly traded equity positions; the fund itself has not been liquidated.
How 4x Leverage Led to a Margin Call
According to analysis from SpotGamma, Situational Awareness LP had built up long positions in AI stocks with gross exposure roughly four times its own capital. That analysis puts the size of the liquidated book at around $20 billion in AI stocks, a figure covering a different scope than the $16 billion pre-sale public equity portfolio reported by the FT. In leveraged investing, borrowed funds are layered on top of capital posted as margin to inflate position size, meaning that price movements in the underlying assets are amplified many times over when reflected as gains or losses on that capital.
When the maintenance margin ratio falls below a certain threshold, brokers demand additional collateral. If the shortfall isn't resolved, the broker forcibly closes out the position. According to a report from thenextweb, three prime brokers—Goldman Sachs, JPMorgan, and Bank of America—were assisting with meeting margin requirements and reducing positions.
The scale of this amplification effect is visible in the outcome: the fund's assets fell roughly 77.8%, from $45 billion to $10 billion. With gross exposure (combined long and short positions) at four times capital, even a much smaller move in the underlying assets gets amplified into a far larger swing in capital gains or losses. However, since the 4x figure represents combined gross exposure across both long and short positions, it's not possible to simply back out the decline rate of the long positions alone through straightforward division. In fact, it appears that short positions in software stocks such as Adobe moved against the fund as those stocks rose, compounding the losses from the long side—suggesting the actual breakdown of gains and losses was considerably more complex.
According to Q1 2026 13F filings (institutional equity holdings disclosures) compiled by SpotGamma, Situational Awareness LP's top holdings included Bloom Energy (22.8%), SanDisk (18.8%), and CoreWeave (14.4%), with the top five holdings accounting for more than 76% of the disclosed portfolio. With such concentrated positions layered with 4x leverage, a sharp drop in just a handful of AI infrastructure stocks was enough to rapidly erode the fund's capital.
Over $460 Billion Lost Across Three Chipmakers: The Reality of the AI Infrastructure Stock Rout
The unwinding of Situational Awareness LP unfolded in step with a broader selloff hitting AI infrastructure stocks across the board. According to a CNBC report from July 29, the three major semiconductor giants—SK Hynix, Samsung, and Micron—lost a combined market capitalization of over $460 billion in a single week. The breakdown was $176 billion for SK Hynix, $173 billion for Samsung, and $113 billion for Micron—all three being major suppliers of AI-focused memory chips.
That same week, SoftBank shares also fell 6.95%, as the turmoil rippled across Asian markets broadly. SoftBank is widely viewed as a proxy for AI-related investment through its stake in Arm (the UK-based chip design giant), among others, meaning that any wavering in AI stock valuations feeds directly back into concerns over unrealized gains on its investments, and thus into its own share price. Converted to yen, Situational Awareness LP's current asset base of $10 billion equates to roughly ¥1.59 trillion (at ¥159 to the dollar), a figure that the weekly market cap decline across the three chipmakers exceeds by an order of magnitude. This lineup of numbers makes clear that the sale of a single hedge fund is not an isolated incident, but rather one facet of a broader correction across the entire AI infrastructure stock sector.
Why Did the Man Who Warned of AI's Arrival Undo Himself With His Own AI Stock Bets?
Aschenbrenner is a former researcher on OpenAI's Superalignment team (which focused on the safety of superintelligent AI), and was dismissed in April 2024 over allegations of leaking confidential information. He himself has claimed the real reason for his dismissal was an internal whistleblower memo concerning safety issues, a claim OpenAI has denied. According to a report from thenextweb, in late 2024 Aschenbrenner founded Situational Awareness LP with roughly $225 million in capital, backed by prominent investors including the Collison brothers (Patrick and John), Daniel Gross, and Nat Friedman.
What made Aschenbrenner famous was his own essay arguing that the arrival of AGI (artificial general intelligence) would come sooner than widely expected. The fund's very name, "Situational Awareness," is a nod to that essay. According to techtimes, the fund's net return for the first half of 2026 reached 439%, meaning its bullish bet on AI stocks had, until then, paid off handsomely.
The same bet turning against it through a combination of leverage and concentrated positioning mirrors the 2021 collapse of Archegos Capital Management. Archegos, too, held concentrated leveraged positions in specific stocks, and a sharp price decline triggered a cascade of margin calls, ultimately leading prime brokers to book losses in the billions of dollars. The mechanism was the same, even if the underlying bet differed—Archegos was betting bullishly on individual stocks, whereas Situational Awareness LP was betting on the growth trajectory of the AI industry itself.
The winner here is Citadel's Ken Griffin, who gained the opportunity to acquire a large, distressed portfolio in a single transaction. The losers are Situational Awareness LP's existing investors, and Aschenbrenner's own reputation as a commentator. This episode extends beyond a single fund's risk-management failure, and is being received as a case that raises questions about the sustainability of the AI investment boom as a whole.
Ripple Effects on the Japanese Market and Aschenbrenner's Case for a Turnaround
According to Yahoo Finance, Aschenbrenner, in an investor letter dated July 24, characterized the recent stock decline as a "buying opportunity." The letter reportedly cited expectations for Anthropic's initial public offering (IPO) as a positive catalyst, and took the position that the AI industry's long-term growth narrative remains intact. Situational Awareness LP plans to open a window for accepting new capital from existing clients starting August 1, and intends to continue operating as a private equity investment firm.
Whether this optimistic outlook plays out hinges on how Anthropic's valuation is priced in the public market. The roughly $5 billion stake in Anthropic is said to be the largest holding among the private equity positions excluded from this sale, and if an IPO materializes and that valuation is validated by the market, it could provide a foothold for restoring the fund's reputation. Conversely, if skepticism spreads more broadly regarding private valuations of AI companies, Aschenbrenner's "buying opportunity" call would carry the same fragility.
The market cap declines at SK Hynix, Samsung, and Micron, along with the drop in SoftBank shares, show that the AI boom's correction is not confined to North American markets alone. For Japanese investors, share price swings among the companies that form the core of the semiconductor supply chain feed back indirectly into asset formation. It is an ironic ending that a fund named "Situational Awareness" misjudged the very situation its own positions were in. The next focal point will be how Anthropic's valuation is tested in the public market—and that will determine whether Aschenbrenner's "buying opportunity" call was justified.