SanDisk surged 11%, storage and chip stocks saw massive trading volume in "short-term options," has the "AI stock guru" made another move?

On Friday, approximately $96 million in short-term call options flowed into four AI chip stocks: SanDisk, Micron, Intel, and Marvell. SanDisk's stock price surged by as much as 11% during the session.

Seeing this massive surge in short-term options trading, CNBC host Jim Cramer posted on social media platform X, exclaiming, "Judging by this, Leopold is back!"

If you've been following investment opportunities in the global AI computing power and large-scale modeling sector, you're probably familiar with Leopold Aschenbrenner.

This former core researcher at OpenAI and founder of the illustrious AI-themed hedge fund Situational Awareness was known for his aggressive use of high leverage to buy short-term call options on semiconductor and AI companies. Starting with approximately $225 million in 2024, his fund grew to approximately $45 billion through highly leveraged AI bets.

In July of this year, the fund suffered a massive margin call, plummeting 67% during the AI sector correction and selling off most of its holdings to Citadel. The Financial Times listed it as the largest single loss in hedge fund history. Despite this, the fund still recorded a positive return of approximately 80% that year.

In a letter to investors at the end of July, Aschenbrenner stated that he would "find another day" and "learn the necessary lessons," and promised that public market investments would be "managed with full payment."

Last week, CNBC reported that the fund had repurchased options on stocks such as AMD, Bloom Energy, and CoreWeave. This time, the focus shifted to memory and chips—its two largest holdings before the crash.

Composition of nearly $100 million in call options

According to intraday trading data compiled by ZeroHedge, the details of these call options expiring on October 2nd are as follows:

• Micron (MU) : Exercise price 1000 , approximately 10,000 warrants, premium approximately 44 million.
• SanDisk (SNDK) : Strike price 1600 , approximately 4200 contracts, premium approximately 41 million.
• Intel (INTC) : Exercise price 115 , approximately 20,000 contracts, premium approximately 7.3 million.
• Marvell (MRVL) : Strike price 250 , approximately 3500 contracts, premium approximately 3.85 million.

SanDisk was trading near its strike price at the time; Micron was around $990, with its strike price almost at par; Intel and [other companies] had strike prices slightly higher than their current prices. Micron and SanDisk's weekly highs were $1255 and $2354 respectively , and their current prices are still quite far from those highs.

Contracts expiring in two weeks have extremely high time decay and gamma sensitivity, leaving almost zero room for error in directional judgment.

Cramer points out that the October expiry date follows Micron's fourth-quarter earnings report—a report that has historically impacted the entire storage sector. He was optimistic about the sector back in August, believing that the demand and supply discipline of AI data centers was reshaping the storage industry's traditional boom-bust cycle.

Why is the market pointing to "AI stock market geniuses"?

The SEC filing has not yet disclosed the buyer's identity, but there is ample speculation in the market about Aschenbrenner.

The most direct clue is the underlying assets. Situational Awareness's regulatory filing at the end of June showed that SanDisk held approximately $5.7 billion and Micron approximately $5.6 billion, making them its two largest positions. This nearly $100 million in option premiums is concentrated in the same two stocks.

The trading methods also align. This fund was previously known for its extremely high short-term leverage bets on AI momentum, with leverage ratios reaching as high as 400%. Short-term, large-scale call options were its signature tool—triggering market makers' gamma hedging buys through large-scale purchases, driving short-term price surges.

The timeline also aligns. According to a Financial Times report on September 11, Aschenbrenner had rebuilt positions in AMD, Intel, SK Hynix, SanDisk, and CoreWeave through flex options. Nomura strategist Charlie McElligott noticed a signal at the time: a total of $315 million in option premiums flowed into AI and semiconductor stocks over several days, involving a Delta exposure of $1.1 billion. He also noted that the skewness of call options on semiconductor ETFs over the next three months had surged to a record high.

The tools have changed, but the logic remains the same.

Unlike in July when he relied on total return swaps (TRS) provided by major banks such as Goldman Sachs to obtain leverage, Aschenbrenner is believed to have switched to fully-paid options this time—the maximum loss is limited to the premium already paid, and theoretically there is no risk of margin calls or liquidation.

This shift has real-world reasons. Following the collapse, JPMorgan Chase terminated its lending relationship with the fund, the SEC has requested information from the banks that financed it, and the brokerage firm it previously partnered with is under investigation by the U.S. Department of Justice. According to the Financial Times, Aschenbrenner has turned to Clear Street, a brokerage firm focused on the technology sector, to re-establish a partnership.

However, the underlying strategy remained fundamentally unchanged. McElligott observed that these trades exhibited a correlation between rising spot prices and rising volatility—a pattern highly similar to that before the July crash. They still established large, concentrated exposures in momentum assets with limited liquidity, intending to trigger a chain reaction of price increases. Once momentum reversed, the premiums were wiped out, and there was no way to mitigate this by adjusting leverage.

The fund's third-quarter 13F report will be filed in mid-November, at which time the true buyers of these transactions will be identified from regulatory filings.

Risk warning and disclaimerInvesting involves risk; please exercise caution. This article does not constitute personal investment advice and does not take into account the specific investment objectives, financial situation, or needs of individual users. Users should consider whether any opinions, views, or conclusions in this article are suitable for their specific circumstances. Any investment decisions made based on this information are at your own risk.