The #Firefish word #trademark is registered for NICE classes 9, 41, 42, i.e. computer software and services etc., for the whole of the European Union (and I believe for the UK too, not checked). Server admins in those jurisdictions, you may want to avoid domains containing the word or at least get legal advice before deploying a server with such a domain - this could potentially be costly otherwise.
@choyer@fediversenews@feditips The rule with domains is: Whoever gets the domain first, gets it. Trademarks have no meaning with domain names. Reminds me of the German person who bought a Google domain when they forgot to renew it. Google had to pay up. It was legally that person's domain and there was nothing Google could do other than buying it from that person.
@choyer@fediversenews I should also add, that if the trademark is registered under "computer software and services", that means it's still available for other categories. You could create a detergent called Firefish and legally register it, because it falls under another category (assuming no one did that before you).
Now, you might tell me that I'm wrong about that, too. To which I will only say, Linux (the kernel) is a registered trademark, but also only for a certain category, which is why this is possible: https://www.roeschswiss.com/en/11_linux
And yes, it's a real product, I've seen it in grocery stores. And yes, they have a registered trademark on Linux (for another category).