[expazl]

Micky mouse was inspired by "a real world animal". That doesn't mean that all IP is suddenly void.

[jevoten]

But it does mean other cartoon mice don't necessarily infringe on Mickey, even though nearly all could be argued to be "inspired by" him.

[Ekaros]

Just looking at various Warner Brothers properties and it is pretty clear that you can do lot even in something that is somewhat similar in style. If not in substance.