The Defense of the Ancients trademark recently filed by Valve is being challenged. Riot Games, the creator of the free-to-play DotA clone League of Legends, has apparently counter-filed, claiming that the trademark should be held by DotA Allstars creators Steve "Guinsoo" Feak and Steve "Pendragon" Mescon, who later worked with Riot on LoL.
The pair filed for the trademark themselves "to protect the work that [original DotA creator] Eul, Guinsoo and dozens of other modders have done to create the game," Pendragon told Joystiq via email. He added that, "if we were to obtain the trademark, we would keep the game and the DotA name freely available to the mod community."
Valve still hasn't returned multiple requests for comment, but of course DotA's most recent author, Icefrog, now works for the company on a project that will "excite " DotA fans, and as long ago as 2008 was reportedly shopping around a full-scale version of the popular mod. Pendragon tells PC Gamer that he'd prefer no one owned the trademark to DotA, but it seems that if Valve is planning to take the name for its own title, Guinsoo and Pendragon will fight for it.