You mean the AI model itself, the weights?

A derivative work is a creative expression based on another work that receives its own copyright protection. It's very unlikely that AI weights would be considered a creative expression, and would thus not be considered a derivative work. At this point, you probably can't copyright your AI weights.

An AI might create work that could be considered derivative if it were the creative output of a human, but it's not a human, and thus the outputs are unlikely to be considered derivative works, though they may be infringing.