I just assume that this would only be resolved at the Supreme Court level. Any local court decision would be challenged by Twitter.
Re: @Microsoft. I am not convinced that’s the case. If I build a public website with user handles it doesn’t automatically give all trademark owners the right to the matching handle.
> I just assume that this would only be resolved at the Supreme Court level. Any local court decision would be challenged by Twitter.
That's not how the Supreme Court works. The Supreme Court only agrees to consider a small number of cases every year, which are usually cases that could have a significant impact on constitutional law. If the Supreme Court refuses to hear a case, the decision of the lower court (federal appeals court) would stand.
That maybe true - I don't know much about the legal system. However, my guess is that the implications of being able to lock down vs seize and sell user handles in private companies are more far reaching than some of the recent cases the Supreme Court did agree to consider, e.g. whether "Trump too small" can be trademarked.
If you want to send tweets as @Microsoft after they leave the platform, you’re going to run into Trademark law among other issues.