To be exact, they currently send around "Abmahnungen" (written warnings; http://en.wikipedia.org/wiki/Abmahnung ). Germany is quite "special" in these laws, and there is a lot of abuse of this here. You can just wonder what the actual trademark owners are thinking about this (and how someone can be convinced of officially registering terms like "Gamer").

They secured these terms: 3020130411641 | Sheldon Cooper 3020130411668 | Geek Nerd 3020130531612 | Barney Stinson 3020130537076 | Walter White 3020130606299 | Gamer

(registrations can be viewn here: https://register.dpma.de/DPMAregister/marke/einsteiger )

More information on the blog of the biggest affected shop: http://www.getdigital.de/blog/fall-trade-buzzer-abmahnung-ge...