User blog comment:Mattd43/The Blue Beetle/@comment-174.55.127.157-20131117034304/@comment-174.99.19.200-20131117164325

The thing is, in the US trademarks don't have to be registered, you have what is called "common law trademarks". Registration helps, especially if you're pursuing damages.. But, all DC has to show is that they have put out a book or advertising in the recent past with the title and character that someone doing a new comic would surely know about.