Is Captain Atom Trademarked?

Okay, I'm talking the original Captain Atom (Allen Adams) by Charlton, his silver age stuff is in the pd but I dont know whether or not his name is trademarked. It doesn't say so on pdsh so...?

http://tess2.uspto.gov/ is where to go online to search the United States Patent and Trademark Office database for active Trademarks. However, the USPTO's online database only contains entires for registered & pending applications.

According to USPTO's FAQ, a Trademark does not have to be registered in order for someone to have a valid claim of ownership. A Trademark is "registered" when it uses the ® symbol. Whenever you see the ™ symbol, someone is claiming ownership of a Trademark without the benefits that a registered mark provides, and, more importantly, that claim of ownership will not turn-up in an online search.

DC Comics may have claimed a Trademark on the name without registering it with the USPTO. Most comic companies will use the ™ symbol until a property/character reaches the point that spending the time & money to register the mark is worthwhile. Since an online search for "Captain Atom" turned-up nothing, I would suggest looking at recent covers where the name has been used to see if CA's name carried the ™ symbol.