Germans apparently allow all sorts of English words to be trademarked. I ran into the problem buying Google ads, and the ads would get rejected for a trademark violation. The whole campaign would get messed up because I targeted english speakers worldwide and the ads got rejected because the word "immersion" is trademarked in Germany.
Edit: I think Google has since improved the error message and gives a message like "Ad is running, but cannot be run in all regions due to a trademark issue." Adwords used to just reject the ad with ominous text "trademark violation".