Ever-Infamous Kojiro-san
So wait: if DC and Marvel OWN the word "superhero" then does that mean Image is in trouble for creating "superhero" comics? And does that also mean that other "superhero" comics cannot be made unless it's under the watchful Big Brother-esque eyes of DC or Marvel?
That is so totally not how coypright/trademark works.
Them having a trademark on the word Super-Hero means you cannot have a product or character called Super-Hero, the "concept" of a super-hero cannot be trademarked or copyrighted.
For example: If I wanted I could create a book about a guy with Spider-Powers. Marvel does not own the concept. However, if I were to make it about a high school kid who got his powers from a radioactivity experiment whos parents are dead and he lives with his aunt and uncle and he uses his powers inapporpriately untill his uncle is killed as a result? Then Marvel could sue my a** up and down. Because that concept is copyrighted.
Now, say I come up with a totally original concept for the book, and call it "The Spider-Man From Mars" Marvel could totally sue me because the word "Spider-Man" is trademarked by them, and I cannot use it in the title of my product.
Super Hero Happy Hour had to change its name to Hero Happy Hour, not because the book dealt with super-heroes, but because the word "Super Hero" was in the title of their book.
Marvel and DC do not own the concept of a super-hero. That is far too broad an idea to be copyrighted. They do however, own the trademark, which is basically the words "Super" and "Hero" when used together as the name/title of a character or product.