Its own screen, whole market
Sell the pre-market spike
This strategy sells short. Every return below is the position's — the stock's move with the sign reversed. It is a measurement of where the system's information lives, not a recommendation to sell anything.
Sessions
10
Mean return
+2.02%
vs S&P 500
+2.00%
Verdict
no verdict yet
The hypothesis, as registered
A liquid stock up fifteen percent or more before the open has usually been bid up on thin volume by people who will want out once real volume arrives. On a hundred replayed sessions, buying the largest pre-market gap won only 38% of the time. The pre-market leader strategy stops at +15% for that reason; this one starts there, and sells.
The rule
Among stocks with average volume over 2M and price over $10 that traded in the pre-market: gap of +15% or more against yesterday's close. Sell short the largest, hold to the close. Abstains when nothing qualifies, which will be most mornings.
Session by session
| Session | Pick | What the rule read | Return | vs S&P 500 |
|---|---|---|---|---|
| 2026-10-14 | passed | No liquid stock was trading 15% or more above yesterday's close in the pre-market. | — | — |
| 2026-10-13 | passed | No liquid stock was trading 15% or more above yesterday's close in the pre-market. | — | — |
| 2026-10-12 | WFFWF Holding Limited | pre-market gap +360.98% · average volume 7,565k · 5-day return +411.02% | +16.91% | +17.00% |
| 2026-10-09 | SECZSecuritize Corp. | pre-market gap +18.16% · average volume 5,494k · 5-day return -7.86% | +4.70% | +4.40% |
| 2026-10-08 | BSPBending Spoons S.p.A. | pre-market gap +17.24% · average volume 3,110k · 5-day return +23.26% | -3.28% | -3.16% |
| 2026-10-07 | OPCHOption Care Health | pre-market gap +32.73% · average volume 5,361k · 5-day return +35.91% | no price found | — |
| 2026-10-06 | PTCPTC Inc. | pre-market gap +33.56% · average volume 3,122k · 5-day return +37.63% | -0.11% | -0.23% |
| 2026-10-05 | XPXP Inc. | pre-market gap +18.56% · average volume 8,235k · 5-day return +4.83% | +8.94% | +8.27% |
| 2026-10-02 | MATMattel | pre-market gap +18.09% · average volume 6,366k · 5-day return +14.46% | +0.89% | +1.01% |
| 2026-10-01 | ACNAccenture | pre-market gap +21.40% · average volume 5,331k · 5-day return -0.08% | -1.70% | -1.66% |
| 2026-09-30 | IOVAIovance Biotherapeutics, Inc. | pre-market gap +33.67% · average volume 17,259k · 5-day return +35.81% | +0.89% | +1.38% |
| 2026-09-29 | KODKodiak Sciences Inc | pre-market gap +170.79% · average volume 2,757k · 5-day return +177.36% | +4.14% | +4.48% |
| 2026-09-28 | passed | No liquid stock was trading 15% or more above yesterday's close in the pre-market. | — | — |
| 2026-09-25 | GRMLGreenland Mines Ltd | pre-market gap +51.97% · average volume 21,409k · 5-day return +399.66% | -11.15% | -11.49% |