To Sue's concern over poaching:
 
The problem becomes even more incidious when the image being poached is
something that has a greater resonance and potential for cultural
comment.  An artist wishing to critique the feel-good mythologizing
that's implicit in Disney's vision of America can be prevented from
incorporating Mickey or another image--images which have a closely
knit relationship with American culture--into a work.
 
For more on the legal discourse surrounding the ownership of images see Jane
Gaines's new book.