Why Options Dealers Can Move the Market (Gamma Exposure Explained)

Some days the market drifts. Other days it swings hard and nobody can say why. Part of the answer is options dealer hedging, and here is how to see it on the terminal. Dealers sell options to traders, then hedge that risk by trading the underlying stock or ETF.

How they hedge depends on something called gamma. When dealers are long gamma, they sell rallies and buy dips. That calms price down. When they are short gamma, it flips.

They buy as price rises and sell as it falls, and that can make moves bigger. This chart shows gamma strike by strike. Call gamma sits above the zero line, put gamma below it, and the dashed marker is where price trades right now. The call wall is the strike with the most net call gamma.

The put wall is the strike with the most net put gamma. Price often reacts around them, though not every time. Zero gamma is the price where the estimated total gamma flips sign. Further down, open interest shows where contracts are stacked up by strike.

Big clusters are one reason those walls can matter. You can try this on any ticker in the free trial. The signals panel turns all of it into plain labels: likely support, likely resistance, and where volatility could pick up. One caution.

Gamma exposure is an estimate: each option's gamma times its open interest, plus an assumption about which side dealers hold. Treat it as context, never a forecast. For information only, not financial advice.