The trademark has been filed in Germany by a German events directory. Their main focus appears to be club events, not nerd events and indeed there is only one listing from mid last year for a hackathon.
Are they getting into the trademark troll business on the side?
Edit: The agency also has a word mark on "Nerd Zone", both seem to be motivated by this: http://www.nerd-zone.com/hackathon.
Here is the claimed background for this http://www.young-targets.com/formation-of-tech_hub-started/
with implying that most of the people are on board with this - most of the organizer used in that image however where only asked if they liked the idea of the techhub nothing more. The good thing about the connected world is that those kinds of statements can be easily verified.
The discussion is happening with the guy here https://www.facebook.com/groups/159595270791268/permalink/44...
if you don't like to join, you can see statements of organizers also here https://www.facebook.com/nicole.simon/posts/1015164077361130...