UPDATE: Domain registrations attributed to CBS Films indicate Human Defiance is, in fact, related to the motion picture. The original story follows.
Square Enix has filed for a new trademark in the Deus Ex brand. The application, spotted on NeoGAF (via CVG), is for "Deus Ex: Human Defiance" and was submitted on February 26.
The trademark follows the name scheme established in Deus Ex: Human Revolution. We're not aware of any upcoming projects within the franchise, aside from that movie adaptation plodding along with CBS Films.
The title's initials are "HD," so aside from a wholly new project it might be a remake of some kind.