Gamma flip
Also called zero gamma level, gamma flip point
The gamma flip is the price at which modeled net dealer gamma changes sign, separating the range where hedging dampens moves from the range where it amplifies them.
In more detail
Above the flip, dealers are typically net long gamma: their hedging leans against price, and sessions tend to be quieter and more mean-reverting. Below it, they are typically net short: hedging leans with price, and moves tend to extend.
Because the flip is a level rather than a signal, traders use it as context. Price crossing it does not mean buy or sell; it means the character of the tape may change.
A ticker can legitimately have no flip. If modeled net gamma never crosses zero across the strike range, there is no crossing point to report — and a page that printed 0 in that case would be inventing a level rather than reporting one.
How Hermes measures it
Hermes reports the flip per ticker on its public market page and omits it entirely when net gamma does not cross zero, rather than defaulting to a number.
Read this on a live chart.
Hermes puts dealer positioning next to price through the session. Free to use.