What Is Gamma Scalping? Market Maker Hedging Explained

The Market Maker’s Goal

Options market makers do not want to bet on the direction of the S&P 500. Their goal is to remain Delta Neutral. If they sell you a call option (giving them negative delta), they immediately buy shares of the underlying asset (positive delta) so their net exposure to the market is zero.

However, as the market moves, Gamma changes the option’s delta.

The Mechanics of Gamma Scalping

If a market maker is long Gamma (they bought options from retail), their position’s delta will increase as the market rises. Because they want to stay delta neutral, they must sell stock to offset the new positive delta.

If the market then drops, their delta decreases, and they must buy stock to remain neutral.

By constantly buying low and selling high in small increments as the market chops around, the market maker is Gamma Scalping. This process generates enough profit from the stock movement to pay for the Theta (time decay) of the options they hold.

Why it Matters for 0DTE

When dealers are short Gamma (they sold options to retail), the hedging process works in reverse. They are forced to buy stock when the market goes up, and sell stock when the market goes down.

This forced buying and selling throws gasoline on the fire, accelerating market trends and creating the violent, directional intraday moves that 0DTE traders aim to capture.