Aren't trademarks a national level issue like patents? If so couldn't multiple companies around the world all be called Dahon and have a reasonable claim on Dahon.com?
Trademarks, like patents, are registered with the federal government in the US, as well as copyrights. May be different in other countries. You can also apply for international patents(and pray that they are honored), and apply for foreign patents as well. Not sure how this translates to trademarks.
As far as the 'controversy' this keeps generating..."There's no such thing as bad publicity" - Jane Mansfield.