Narration: AI voice.
The number
Wednesday, October fourteenth, 2026. SPX down 1.11%. By noon it had crossed the gamma flip. It closed below it. Here's the dated record, straight off the session page.
The morning
Ten a.m. Spot 7,780.38. The page reads: session opened in positive gamma, flip at 7,739.6, 40.8 points beneath spot. Under the model's dealer convention, hedging dampens moves. That's a model line, computed once that morning from open interest settled the day before.
The cross
A flip cross is spot moving through that line, and the modeled regime switching sides. Noon: spot 7,730.49. In the page's words, spot crossed the flip into negative gamma, so dealer hedging now amplifies moves. That's the model's read under its assumed dealer positioning, not a measurement. And most of the day's drop came before the cross: by noon spot was already 49.89 points under the ten a.m. snapshot. The close: 7,718.94, down 86.51 points, 20.67 below the morning flip. High to low, 95.84 points.
The next morning
Next morning, Thursday the fifteenth. New settlement, new levels. Session opened in negative gamma, flip 33.2 points above spot. The put wall relocated 150 points higher, to 7,650 from 7,500. The flip moved 10.4 lower, to 7,729.2. Then spot crossed it five times that session.
Wrap
One session, one dated record. Not a tally, not a forecast. The flip is a model line, recomputed every morning from settled open interest. How it's built is on the learn page linked below. Educational only.
Full write-up with sources: /learn/spx-gamma-levels
Educational content, not investment advice.
Levels shown are as captured on 2026-10-16 01:43 ET; they are not current.