# Gamma Flip (Zero Gamma): The Regime Line on One Page Source: https://squawkflow.com/videos/gamma-flip-regime-line Retrieved: 2026-10-17T16:08:08.200Z Uploaded: 2026-10-16 Duration: 7:04 Topic: Options Greeks Video file: https://storage.googleapis.com/squawkflow-videos/gamma-flip-regime-line/gamma-flip-regime-line-358a7f7c.mp4 Captions: https://storage.googleapis.com/squawkflow-videos/gamma-flip-regime-line/captions-6777101f.vtt What the gamma flip is, how it is found, why it moves every morning, how crosses are logged, and what it cannot tell you. Dated records. AI voice. AI voice: the narration is a synthetic voice reading a script SquawkFlow wrote. Educational only, not investment advice. Nothing here is a forecast or a recommendation to trade. ## Chapters - 0:00 One line, three names (https://squawkflow.com/videos/gamma-flip-regime-line?t=0) - 0:28 What the flip is (https://squawkflow.com/videos/gamma-flip-regime-line?t=28) - 1:26 How it is found (https://squawkflow.com/videos/gamma-flip-regime-line?t=86) - 2:50 A morning figure that moves (https://squawkflow.com/videos/gamma-flip-regime-line?t=170) - 4:13 Crosses, and the neutral case (https://squawkflow.com/videos/gamma-flip-regime-line?t=253) - 5:34 Not the vol trigger (https://squawkflow.com/videos/gamma-flip-regime-line?t=334) - 6:11 What it is not (https://squawkflow.com/videos/gamma-flip-regime-line?t=371) ## Related - Explainer: https://squawkflow.com/learn/gex-flip-price-explained ## Transcript # Gamma Flip (Zero Gamma): The Regime Line on One Page Narration: AI voice. ### One line, three names One number on the SPX gamma page splits the board in two. Captured October 16, 2026: spot 7,663.20, zero-gamma flip 7,729. Gamma flip, zero gamma, the regime line. Three names, one level. Here's what it is, how it's found, how it moves every morning, and what it can't tell you. ### What the flip is Definition. Take the whole SPX options book. At each index price, add up the modeled dealer gamma across every strike and expiry. Plot that total against price. Somewhere it crosses zero. That price is the flip. In the page's words: the index price where net dealer gamma crosses zero. Above it, the model has dealers net long gamma. They hedge against the move: sell strength, buy weakness. That damps moves. Below it, they hedge with the move, and that amplifies it. That's why it's called the regime line. And every word of that is conditional on the assumed positioning. The page says it straight: that's the flow the convention implies, not a measurement of how often price has behaved that way. No hit rate is published for it. ### How it is found How is it found? Not by watching trades. Start from settled open interest on every strike and expiry. Value each contract's gamma with an options pricing model and an implied volatility surface. Sign it from the dealer's side: calls positive, puts negative. Then, at each possible price, sum the signed gamma. Where the total equals zero, that's the flip. So there are three inputs. Settled open interest. Implied volatility. And an assumption about who holds what. Change any one of them and the line moves. You can watch that happen on the page. The tile's flip is 7,729. Underneath, the repriced block, stamped Oct 16, 13:30 ET: same open interest, settled October 15, 2026, revalued at spot 7,667 and that read's implied volatility. Zero gamma there: 7,728. Regime: negative. Same positions, a different spot and volatility read, a different line. The positions themselves aren't updated intraday. Open interest is published once a day. ### A morning figure that moves Now the dates. The flip is a settlement figure. It's computed in the morning from open interest settled at the prior session's close, and it does not update through the session. Here's the closed record for October fourteenth, 2026. Ten o'clock: spot 7,780.38, session opened in positive gamma, flip 40.8 points beneath. The log's read: dealer hedging dampens moves. Morning flip, 7,739.61. It sat 0.85 points lower than the prior session's, on new open interest. Line up four mornings. October twelfth, 7,722.92. The thirteenth, it relocated higher, to 7,740.46. The fourteenth, 7,739.61. The fifteenth, lower, to 7,729.20. Nobody drew a new line. The open interest settled, the book got re-priced, the zero crossing landed somewhere else. Yesterday's flip is a stale answer to today's question. ### Crosses, and the neutral case Mostly, the regime is which side of the flip spot sits on. The session record tracks it on a thirty-minute grid. October fourteenth, noon: spot 7,730.49 crossed the flip into negative gamma, and the log's read switches to: dealer hedging now amplifies moves. October fifteenth, as of 16:00 ET: 5 flip crosses in a single session. So "we're in negative gamma" is a statement about where price is right now, not a standing condition. And a cross that happens between two snapshots is invisible to the grid. The log says so itself. Sometimes the record won't name a side at all. September eighteenth, 2026: regime neutral. Morning flip 7,617.59, 20.2 points beneath spot, and the session opened with no gamma side called, because the two estimators of dealer positioning disagree near the flip. That's the honest answer. Close to the line, two defensible estimates can land on opposite sides, and the page says so instead of picking one. ### Not the vol trigger One more line sits close by: the vol trigger. On this capture, 7,761, against a flip of 7,729. Different number, different definition. The flip is where total dealer gamma crosses zero. The vol trigger is a second regime level, and providers build it differently: some from vanna and charm flows, some as the lowest positive-gamma strike between the walls. On this page, it's the second. Related. Not interchangeable. ### What it is not What the flip is not. It's not a volatility call, and it's not a direction call. The page says the gamma sign describes modeled exposure under the assumed positioning, not a forecast of volatility or direction. And the positioning really is assumed. Researchers who rebuilt the actual market maker book from Cboe trade records found its gamma, quote, while typically positive, is often negative. There's no hold rate on the page either, on purpose. So: the zero crossing of modeled dealer gamma, set each morning from settled open interest, a regime named by which side spot sits on, dated every time. The learn page is linked below. Educational only. Full write-up with sources: [/learn/gex-flip-price-explained](/learn/gex-flip-price-explained) Educational content, not investment advice. Levels shown are as captured on 2026-10-16 13:34 ET; they are not current.