https://optioncharts.io/options/SPY/open-interest?option_type=all&expiration_dates=2025-10-07:w&chart_type=line&strike_range=all I've left the graph settings for you. The simplest visual understanding of the gamma ramps is this. You see how there was a call cliff from 670 to 669. That is roughly where the ramp ended. SPY at start of day was around 673 (it opened at the top of gamma ramp, same same.but call side). At this time all the calls on that green line were hedged, meaning shares held for risk of excise today. Then the marketed started moving back down rhe ramp to neutral. Those hedges sold as chance of being ITM decrease, while also short sales open to hedge the puts increasing chance of being ITM. The combination of both dehedging calls and hedging puts is considerable. But eventually the call volume being ITM falls off so the rate of movement slows, which then slows down the short selling as the rate of change of delta slows down (gamma), while theta burns along. This generally results in a minor reversal as probability calculations now factor in the deceleration in movement. You have seen this happen day after day, just its usually on the call side for a positive ramp.

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