Market makers aggregate their risk exposure across all of their holdings and put limits on how large those exposures get. > Aren't these market makers sitting

Market makers aggregate their risk exposure across all of their holdings and put limits on how large those exposures get. > Aren't these market makers sitting on a ton of stock to cover call positions? The whole purpose of delta hedging is to make them immune to the first-order effects of market moves. The first-order derivative of the value of everything they hold with respect to price moves in any one stock is constantly kept near zero. In the old days, many options traders would put off hedging their books until near the closing bell. Smart equities traders would watch the options market to see which way the traders would be rushing to hedge in the cash equities market. These days, there are systems that automatically hedge out the positions throughout the day.