Bethesda Trademark Could Hint at Skyrim DLC

Apart from some updates, Skyrim has yet to get its first DLC content. Is this about to change?

Bethesda parent company ZeniMax Media filed a trademark in February for "Dawnguard" relating to video game software, including downloadable content. The application does not specify anything else, and doesn't mention Skyrim specifically.

Speculation tabs Skyrim because of the Mythic Dawn cult in the series, as well as the Redguard race.

Could this be the game's first DLC content or is it something not even Skyrim related?

[Thanks to Commander Shepard for the news tip!]