Strategy (MSTR), the largest corporate holder of Bitcoin, has become the most heavily shorted stock in the U.S. market, according to Goldman Sachs and FactSet data. Short bets on MSTR equaled 14% of its $34 billion market cap at the time of the report, the highest among all stocks with a market cap over $25 billion. Crypto exchange Coinbase (COIN) ranked fourth with 11% short interest. Yet this may not reflect pure bearishness.
BTC Holdings Show $7B Unrealized Loss, Short Interest Surges
Strategy holds 717,722 BTC worth about $47 billion, with an unrealized loss of roughly $7 billion. The loss has no near-term impact on the stock, but MSTR shares have fallen 20% year-to-date, bringing its market cap to ~$42 billion. The elevated short interest has drawn attention to the underlying trading strategies.
The Basis Trade: Long IBIT, Short MSTR
Analysts point to the basis trade as the main driver. Traders buy Bitcoin spot ETFs (e.g., BlackRock's IBIT) while shorting MSTR, betting on a narrowing of MSTR's premium to its BTC holdings, plus funding from paired futures. This market-neutral strategy does not rely on directional price moves.
Brian Brookshire, a bitcoin treasury specialist, said: "I suspect a lot of this short interest is still MSTR / BTC basis trade. Jane Street, in particular, has recently acquired a conspicuously large IBIT position." Recent 13F filings show Jane Street bought over 7 million shares of BlackRock's iShares Bitcoin Trust while holding a large MSTR position. If accurate, the short build-up is not fundamentally bearish.
Basis Trade Not Profitable This Year
So far in 2026, the MSTR-to-IBIT ratio has risen about 12%, meaning MSTR has outperformed IBIT on the downside. MSTR is down 20% year-to-date versus IBIT's 27% drop. The basis trade would have lost money. Nevertheless, traders may persist, betting on premium convergence.
In summary, MSTR's top short ranking appears to reflect hedge funds exploiting structural arbitrage rather than a broad bearish consensus on Bitcoin or Strategy's fundamentals. The true sentiment may be better gauged by MSTR's premium changes.