What Is the Gamma of a Deep ITM Option?
The Gamma of a deep In-the-Money (ITM) option is very close to zero. Gamma measures the rate of change of Delta.
Since a deep ITM option's Delta is already near its maximum of 1.0 (or -1.0) and changes very little with small movements in the underlying price, its Gamma is low. This means the Delta-hedge for a deep ITM option is very stable and requires minimal re-adjustment.