Does TM Law Limit Superman's PD Reproduction?

Dear Rich: In another entry, you mentioned that there were public domain Superman strips. If someone published a book of the public domain Superman strips, would that be infringing upon Superman as a trademarked character? Or would it infringe (if at all) only if the book title included Superman? Would a generic title get around that? Or does the fact that those particular strips are now public domain outweigh any trademark concerns? You're within your legal rights to simply reproduce the public domain Superman strips. And you're within your rights to use Superman within the title of your book, provided that it accurately describes the source -- for example, "Forgotten Superman Comic Strips from the 1940s," "Superman in the Public Domain." (Here's an entry explaining how the Superman character survived falling into the PD). You may run into problems with Superman's trademark owners if you reproduce the public domain strips on merchandise or if you use them to sell a product or service other than the republished comics.
The mutant copyright. The world of character trademarks vs. public domain source material is not black and white as we discussed in an entry about Sherlock Holmes, and as Stephen Fishman writes in his public domain treatise: "[W]ill “Mickey Mouse” cease to enjoy trademark protection when the original cartoon on which it is based enters the public domain in 2024? No court has definitively answered this question." One thing seems clear, the Supreme Court does not support using trademark law to make an end run against the public domain. If trademark law could do that, as Justice Scalia wrote, it would "create a species of mutant copyright law that limits the public's 'federal right to "copy and to use"' expired copyrights."