Richard Wheeler reports that some literary heirs have found a way to undermine public domain — they trademark the name of the author, as Zane Grey’s estate has done with his name.
What the trademark accomplishes is to make it impossible for anyone to
publish a Grey novel that has fallen into the public domain unless the
publisher licenses the name of the author from the heirs. Oh, you can
print the public domain material, all right; just don’t put the
author’s name on it.
I wonder if this has ever been tested in court? If not, it probably will be soon.