Heavy short-sale volume leads to a squeeze
High short-sale volume is often confused with a large outstanding short position, though they measure different things.
Result
No difference — The test did not establish a difference from the matched baseline.
- Observed up-rate
- 39.5%
- Volatility-matched expected rate
- 40.2%
- 95% lift interval
- 0.95 ~ 1.01x
- Signals · symbols · dates
- 16,772 · 5,241 · 64
As of 2026-10-19 · Observed period 2026-07-13 to 2026-10-14
Source: FINRA Reg SHO daily short-sale volume and DawnScan daily scan records
Rule definition
An event is a day on which FINRA Reg SHO short-sale volume was at least 50% of reported off-exchange volume.
Why people use this rule
High short-sale volume is often confused with a large outstanding short position, though they measure different things.
Results by market regime
| Regime | Cases | Observed | Expected | Verdict |
|---|---|---|---|---|
| Neutral | 3,436 | 30.1% | 31.1% | No difference |
| Risk-on | 13,336 | 41.9% | 42.5% | No difference |
Recent confirmed cases
| Date | Symbol | Outcome |
|---|---|---|
| 2026-10-14 | ATII | -2.5% Delisted (last recorded value) |
| 2026-10-12 | NATH | +0.2% Delisted (last recorded value) |
| 2026-10-08 | GREEL | +0.0% Delisted (last recorded value) |
| 2026-10-07 | ACA | +1.9% Delisted (last recorded value) |
| 2026-10-05 | PERF | +3.6% Delisted (last recorded value) |
| 2026-10-02 | ZVRA | +2.9% |
| 2026-10-02 | ZNB | -71.5% |
| 2026-10-02 | YYAI | -32.9% |
| 2026-10-02 | YB | -13.4% |
| 2026-10-02 | XRPNU | -50.5% Delisted (last recorded value) |
| 2026-10-02 | WSHP | -52.9% |
| 2026-10-02 | WK | +17.4% |
| 2026-10-02 | WHG | -3.9% |
| 2026-10-02 | WDC | -11.8% |
| 2026-10-02 | VXX | +10.4% |
| 2026-10-02 | VFF | -12.0% |
| 2026-10-02 | UUUU | -28.1% |
| 2026-10-02 | UTG | -0.7% |
| 2026-10-02 | TRIN | -3.5% |
| 2026-10-02 | TREX | +17.4% |
| 2026-10-02 | TPG | +4.5% |
| 2026-10-02 | TNGX | -2.2% |
| 2026-10-02 | TEO | -9.5% |
| 2026-10-02 | T | -11.9% |
| 2026-10-02 | SVM | -24.8% |
| 2026-10-02 | STX | -24.1% |
| 2026-10-02 | SSYS | -22.8% |
| 2026-10-02 | SPXC | -7.6% |
| 2026-10-02 | SPTX | +6.4% |
| 2026-10-02 | SPKL | +0.0% Delisted (last recorded value) |
Method and limitations
Definition: An event is a day on which FINRA Reg SHO short-sale volume was at least 50% of reported off-exchange volume.
Historical outcomes only. The sample may reflect a limited market regime. Results do not account for stops, position sizing, fees, or taxes.
Past data · not investment advice