Trademark lawyer Martin Schwimmer of The Trademark Blog brings up a legal issue that has been discussed before but should be of increasing concern (About Three Conundrums After Eldred). The issue is the interaction of trademark and copyright law. As Schwimmer notes, even if Mickey Mouse enters the public domain, Disney still retains a trademark in Mickey Mouse. Thus, even if Eldred wins, it is not clear that Mickey will be freed. This will be one of the next battles in the war over the cultural commons.
Some skirmishes in this coming war have already been fought ... for example, there was an atrocious decision in 1976 that held that there was a liklihood of confusion for any entertainment-related goods and services (such as a movie or book) bearing the "Tarzan" mark. Apparently, people would be confused that a porn movie entitled, "Tarzan & Jane & Boy & Cheetah," was supplied or authorized by Tarzan's author and creator, Edgar Rice Burroughs. Too bad Shakespeare didn't think to trademark his characters. Of course, 1976 was well before "trademark dilution" raised its ugly head (and holders of famous marks no longer had to show consumer confusion).
Speaking of famous marks, one court, in Walt Disney Co. v. Powell (698 F.Supp. 10, 1988), has already determined that, "Mickey and Minnie [Mouse] have acquired not only a secondary meaning, but a meaning of great value, favorable in all respects, and well-entrenched worldwide." Hmmmm...