Key Highlights

  • C4 Therapeutics is trading 7.83% higher at $3.46, with 34.7% of shares outstanding sold short as of October 15, 2026.
  • Jack in the Box has 33.09% of shares outstanding and 51.31% of float sold short, with 11.47 days to cover on the latest available data.
  • Intellia has 44,435,219 shares sold short and an FDA target action date of March 10, 2027 for lonvo-z.
  • Dave & Buster's reported 28.44% of float sold short for September 30, 2026, after a second-quarter net loss of $12.5 million.
  • Biodexa's short position is about 0.83% of shares outstanding, the smallest of the five.

Which Heavily Shorted Stocks Are Trading Higher on October 28, 2026?

Five stocks with notable short positions are trading higher on Wednesday, October 28, 2026. C4 Therapeutics (NASDAQ:CCCC) is trading 7.83% higher at $3.46, with no company announcement dated today. Jack in the Box (NASDAQ:JACK) is trading 6.03% higher at $11.95, with no dated release behind the move. Intellia (NASDAQ:NTLA) is trading 5.82% higher at $12.97, ahead of a March 10, 2027 FDA target date for lonvo-z. Dave & Buster's Entertainment (NASDAQ:PLAY) is trading 4.95% higher at $7.96, and Biodexa Pharmaceuticals (NASDAQ:BDRX) is trading 5.09% higher at $4.13 after an ADS ratio change.

The ranking below uses short interest as a percentage of shares outstanding, highest first. Settlement dates differ: October 15, 2026 for C4 Therapeutics and Intellia, September 30, 2026 for Dave & Buster's, and latest available for Jack in the Box and Biodexa. Dave & Buster's reported its figure against float (28.44%), so its 27.9% of shares outstanding is calculated from 9,733,845 shares sold short and 34.83 million shares outstanding. Short interest shows positioning only and does not predict direction.

1. C4 Therapeutics: What Is Behind the 7.83% Gain in the Most Shorted Name on This List?

C4 Therapeutics is trading 7.83% higher at $3.46, an implied prior close near $3.21 (calculated). No company announcement dated today accompanied the move. The Watertown, Massachusetts company is a clinical-stage biopharmaceutical business that designs medicines to break down disease-causing proteins, built around cemsidomide for multiple myeloma. Its market value is about $426 million (calculated).

Short interest was 42,722,018 shares for the October 15, 2026 settlement date, or 34.7% of shares outstanding, with 16.95 days to cover on average daily volume of 2,520,136 shares. Cash, equivalents and marketable securities were $300.4 million at June 30, 2026, which management expects to fund operations through the end of 2028. Phase 1 data showed a 53% overall response rate at the 100 microgram dose.

2. Jack in the Box: Why Is a Stock With 51.31% of Float Sold Short Trading Higher?

Jack in the Box is trading 6.03% higher at $11.95, against an implied prior close of about $11.27 (calculated). No dated release explains the move. The San Diego company franchises and operates quick-service restaurants, with 149 company-operated and 1,966 franchise-operated restaurants at July 5, 2026, after selling Del Taco.

The latest available short-interest data show 6.35 million shares sold short, equal to 33.09% of shares outstanding and 51.31% of a 12.37 million share float, with 11.47 days to cover. Third-quarter fiscal 2026 revenue was $257.7 million, down from $262.4 million a year earlier, and long-term debt was $1,428.7 million against $46.3 million of cash. Fiscal fourth-quarter results are expected around December 9, 2026.

3. Intellia: Can the March 10, 2027 FDA Date Explain a 5.82% Rise With 31.7% Sold Short?

Intellia is trading 5.82% higher at $12.97, an implied prior close near $12.26 (calculated). No company release is dated today. The latest dated items are a new chief medical officer announced on October 13 and FDA acceptance of its first license application on September 8. Intellia develops CRISPR-based genome-editing medicines delivered inside the body, and its market value is near $1.82 billion (calculated).

Short interest was 44,435,219 shares for October 15, 2026, about 31.7% of shares outstanding (calculated) and not a float-based figure, with 6.45 days to cover. The FDA set a March 10, 2027 target action date for lonvo-z under priority review. In the Phase 3 trial, a single dose cut mean monthly attacks of hereditary angioedema by 87% versus placebo, and cash and marketable securities were $628.4 million at June 30, 2026.

4. Dave & Buster's: What Is Behind the 4.95% Jump With 28.44% of Float Sold Short?

Dave & Buster's is trading 4.95% higher at $7.96. No dated company release explains the move, which follows a 6.70% drop on October 23 to a close of $6.96. A rebound in a heavily shorted stock is a plausible backdrop, though nothing dated confirms it. The company operated 250 stores at the end of the second quarter, 184 under the Dave & Buster's banner and 66 under Main Event.

Short interest was 9,733,845 shares, or 28.44% of float, for the September 30, 2026 settlement, with 3.6 days to cover. Second-quarter revenue fell 2.4% to $544.1 million, comparable store sales fell 2.9% and the net loss was $12.5 million, or $0.36 per share. Long-term debt was about $1.50 billion against $16.0 million of cash.

5. Biodexa Pharmaceuticals: Why Is the Penny Stock Trading Higher With the Thinnest Short Position?

Biodexa is trading 5.09% higher at $4.13, an implied prior close near $3.93 (calculated). No new dated release accompanied the move. Recent events are the October 13 trial update and an ADS ratio change that took effect on or about October 26, 2026, converting eight old ADSs into one new ADS. The UK-based clinical-stage company is focused on familial adenomatous polyposis, with eRapa as its main asset.

The latest short-interest data show 18,380 shares sold short, about 0.83% of shares outstanding, against 271,866 a month earlier, on a reported float of 943,491 shares. On October 13, 2026 the company enrolled its 100th patient in the Phase 3 Serenta trial, out of 168 planned, and a futility analysis after 25 progression events could occur early next year, per that release. Cash and equivalents were 8.534 million pounds at December 31, 2025.

Most Shorted Stocks Compared: How Do the Moves, Short Positions and Days to Cover Line Up?

All comparisons here are calculated from the figures above. The gap between the largest move, C4 Therapeutics at 7.83%, and the smallest, Dave & Buster's at 4.95%, is 2.88 percentage points. The average of the five moves is about 5.94%.

On shares outstanding, C4 Therapeutics (34.7%) sits 1.61 percentage points above Jack in the Box (33.09%) and 3.0 points above Intellia (31.7%). Biodexa's 0.83% is 33.87 points below C4 Therapeutics. On a float basis, Jack in the Box (51.31%) is 22.87 points above Dave & Buster's (28.44%).

C4 Therapeutics has 16.95 days to cover, 13.35 days more than Dave & Buster's 3.6, or about 4.7 times as long. Intellia has 1,713,201 more shares sold short than C4 Therapeutics, yet a shorter cover time of 6.45 days, because its average daily volume is about 6.9 million shares versus 2,520,136.

What to Watch Next: Short-Interest Updates on November 10 and Earnings Dates From November to December

The next short-interest settlement date for C4 Therapeutics and Intellia is October 30, 2026, with publication expected on November 10. Intellia's third-quarter results are estimated for around November 9, and its FDA target action date is March 10, 2027. Dave & Buster's third-quarter report is estimated for around December 8, 2026, and Jack in the Box expects fiscal fourth-quarter results around December 9, 2026. C4 Therapeutics targets an elranatamab dose-escalation update in the second half of 2026, and Biodexa's futility analysis could come early next year.