gap-reversal
Price gaps away overnight, then turns and works back toward where it came from.
What defines it
An open far from the prior close, with no trade in between. The gap leaves an air pocket, and price tends to revisit it — the reversal is the market rejecting the overnight repricing once real liquidity shows up.
What makes it work
A gap driven by sentiment rather than a change in the facts. The first thirty minutes are the tell: if the gap can't extend and the open turns out to be the extreme of the session, the overnight move was thin-liquidity noise and the fill is on. Weak follow-through volume after the open supports it.
What kills it
A gap on genuine news — earnings, guidance, a deal, a rate decision. That gap is a repricing, not a mistake, and it doesn't want to fill; fading it is standing in front of a re-rate. Gap direction against a strong trend is the other trap: gaps with the trend run, gaps against it fill.
What to record
The gap size as a percentage, whether news drove it, and where the session extreme landed relative to the open. The news/no-news split is the line that separates the fills from the runners.