Lady Gaga and/or her management appealed to the National Arbitration Forum. Her claim was that ladygaga.org, which was started by a fan, was a trademark infringement. The owner of the site claimed that she was not gaining any profit from the site and using it solely to promote Lady Gaga.
This is where it gets tricky for an artist who fiercely wants to protect his/her image. Is it worth alienating a fan who is clearly a superfan? The website states on the homepage that it's an unofficial site.
For someone as popular and in the public eye as Lady Gaga, she would have to think situations like this would be sprouting up all over. This fan was smart enough to register ladygaga.org. In checking other domains, .net is another unofficial website, .info redirects to a dance website. It's surprising that Gaga didn't register every domain configuration and redirect them all to her official website.
The official verdict according to the Hollywood Reporter:
Three panelists at the National Arbitration Forum ruled that Lady Gaga had failed to show that respondent lacked legitimate interest in the disputed domain name.
Fan 1, Gaga 0