[missjellyfish]

I'm not entirely sure if this is even possible the way copyright in the EU works today. Be that as it may, at least from my perspective what really prohibits me from actually enforcing GPL on my software is funding. I rarely go beyond sending a stern letter, because anything more would be financial suicide in most cases; I might win but it is incredibly hard to prove damages. Punitive damages don't really exist in the EU (or, to be more precise, in the roman-german law system), at least not to the exterme seen in common law systems.

At least in my case, I'd fight tooth and nail for my software, if I don't have to bear the financial risk.