Michael Burry's Scion: the big short, a book of options and a fund that stopped reporting
The investor made famous by The Big Short filed his last public stock report for September 2025. What the last five reports show, and why options in a 13F are easy to misread.
Who he is and why people copy him
Michael Burry is a doctor who left medicine to invest. He started Scion Capital in 2000 and in 2005 bought credit default swaps against subprime mortgage bonds, a bet that paid off enormously when the housing market collapsed in 2007 and 2008. The story was told in Michael Lewis's book The Big Short and in the film that followed. Since then every move he makes in public is read as a warning or a signal.
The most recent report on EDGAR is for the quarter ending in September 2025. He is reported to have said afterwards that he was winding down the fund, and no later reports appear. That is why this article covers an earlier period than the others.
The ideas behind the portfolio
Burry's approach is deep, document-level research and a willingness to take a view that is very far from the crowd. He looks for assets that he thinks are mispriced, and for risks that the market ignores, and he is prepared to look foolish for years. He has been publicly sceptical of passive investing and of the largest technology stocks, and his positions sometimes follow from that scepticism.
The strategy often uses options. A put gives the right to sell at a set price and gains when a stock falls. A call gives the right to buy and gains when it rises. They cost little compared with the shares they refer to, so a small amount of money can express a large view, and the whole premium can be lost.
What a Form 13F does and does not show
The 13F is particularly easy to misread for a book like this. Options are reported at the value of the shares they cover, not at what was paid for them. A report that shows a put on Palantir at 66.0% of the portfolio does not mean that two thirds of the money is in that bet; the real cost may be a small fraction. The report also does not say whether a put is the whole position or a hedge on shares held elsewhere, or whether a position was closed a week after the quarter ended.
Because of this, the percentages for Scion should be read as the size of the underlying exposure, not as the money at risk.
The portfolio over the last five quarters
The last five reports run from September 2024 to September 2025. The reported value grew from $0.13 billion to $1.38 billion, but in the last two reports almost all of it is the value of the shares that options refer to, not capital. In September 2024 the book was shares and puts on Chinese technology companies (Alibaba shares were 16.4%, with JD.com and Baidu), and in December 2024 it held only shares: Alibaba, Baidu, JD.com, Estee Lauder, Molina Healthcare and PDD.
In March 2025 the portfolio turned to puts: Nvidia puts were 49.0% of the reported value, with Alibaba, PDD and JD.com puts behind. In June 2025 the picture reversed again, to calls: UnitedHealth (18.9%), Regeneron (18.2%), Lululemon (16.4%) and Meta (12.8%). In September 2025 the last report showed 8 positions, led by puts on Palantir (66.0%) and Nvidia (13.5%) and calls on Pfizer (11.1%) and Halliburton (4.5%); the effective number of positions was 2.1.
Ten largest positions at the end of the latest quarter (2025-09-30) and the same names at the start of the period (2024-09-30), as a share of the US-listed stocks in the report (8 positions, $1.4 billion in total).
| Position | 2025-09-30 | 2024-09-30 |
|---|---|---|
| Palantir Technologies (put) | 66.0% | — |
| Nvidia (put) | 13.5% | — |
| Pfizer (call) | 11.1% | — |
| Halliburton (call) | 4.5% | — |
| Molina Healthcare | 1.7% | 8.0% |
| Lululemon Athletica | 1.3% | — |
| Slm | 1.0% | — |
| Bruker | 1.0% | — |
| Ten largest together | 100.0% | 99.1% |
What changed quarter by quarter
The portfolio changed almost completely from one report to the next in each of the last three quarters. In the quarter to December 2024 puts on JD.com, Alibaba and Baidu and the stake in Shift4 were closed and positions in Estee Lauder, PDD, HCA Healthcare and Bruker were opened. In the quarter to March 2025 the long shares in Alibaba, Baidu, JD.com and Molina (together more than 50% of the book) were closed and replaced with puts, mainly on Nvidia.
In the quarter to June 2025 the Nvidia, Alibaba, PDD and JD.com puts were closed and calls on UnitedHealth, Regeneron, Lululemon and Meta were opened. In the quarter to September those four calls were closed, and puts on Palantir and Nvidia and calls on Pfizer and Halliburton were opened. A position held for one quarter is not a theory about the next ten years.
Changes between consecutive filings. A share is measured as a part of the reported stock portfolio; it can move because of price changes too, so read it together with the text.
| Quarter end | Positions | Opened | Closed | Biggest rise in share | Biggest fall in share |
|---|---|---|---|---|---|
| 2024-12-31 | 11 → 13 | Lauder Estee Cos (9.7%), Pdd (9.4%), Hca Healthcare (5.8%) | Jdcom (put) (15.4%), Alibaba (put) (13.8%), Shift4 Pmts (10.2%) | Baidu (+3.5 pp) | Jdcom (−2.0 pp) |
| 2025-03-31 | 13 → 7 | Nvidia (put) (49.0%), Alibaba (put) (13.3%), Pdd (put) (11.9%) | Alibaba (16.4%), Baidu (13.6%), Jdcom (13.4%) | Lauder Estee Cos (−3.1 pp) | Lauder Estee Cos (−3.1 pp) |
| 2025-06-30 | 7 → 15 | Unitedhealth (call) (18.9%), Regeneron Pharmaceuticals (call) (18.2%), Lululemon Athletica (call) (16.4%) | Nvidia (put) (49.0%), Alibaba (put) (13.3%), Pdd (put) (11.9%) | Lauder Estee Cos (−4.5 pp) | Lauder Estee Cos (−4.5 pp) |
| 2025-09-30 | 15 → 8 | Palantir Technologies (put) (66.0%), Nvidia (put) (13.5%), Pfizer (call) (11.1%) | Unitedhealth (call) (18.9%), Regeneron Pharmaceuticals (call) (18.2%), Lululemon Athletica (call) (16.4%) | Lululemon Athletica (−0.8 pp) | Bruker (−0.8 pp) |
What to take away, and what to doubt
The first lesson is how to read options in a filing: never take the percentage at face value. The second is that a famous contrarian is not a stable one. This book swung between bearish and bullish bets, from China to healthcare to technology, in twelve months, so each report is a snapshot of an opinion that changed.
The warnings are plain. A record of one spectacular trade, made nearly twenty years ago, does not predict the next. Short bets lose when prices rise, and a bet against a rising stock can lose all of its premium. And the public reports have ended, so we cannot see what happened next.
Where it meets our bots
Burry buys what the crowd avoids and bets against what the crowd loves, which is a contrarian logic. Our nearest mechanical cousin is the bot that buys sharp short-term dips of the S&P 500 and sells on the rebound; it acts against the move, but it never bets on a fall and uses no options. Our trend bots work in the opposite direction.
All accounts are virtual and public. The guides below explain the rules.
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