Does Trademarks need to be registered to sell in foreign countries? I know copyright is automatic, what about trade secrets?
I can't help but feel something's being set up here. However I'll bite with my 2 pence of knowledge I'm gleaned from my friend that does know about this stuff...
You've got your "tm" trademark, that you can just about slap on anything. That means you're claiming that's your trademark, it's not a right, but the more you say that's your trademark then the more it is useful. That's why companies defend their trademark so harshly. Hoover lost theirs, because now everyone calls it a hoover.
Then you've got your "@r" trademark, that is officially signed off. To get those you go through processes to ensure you're not infringing on other trademarks, and generally have to jump through hoops. These are easier to defend, but still not concrete.
Both can be defended in court, you're much better if you have an @r, but your "tm" that you've been slapping on stuff might also be defensible if it's recognised.
I'm not a lawyer, this is my take on it from what I heard.