The X-Men vs. Mutant X lawsuit, which was settled earlier, has led to a new lawsuit.
For those late to the whole controversy, ICv2 does a good job of summarizing it. When 20th Century Fox licensed X-Men for its movies, they were riled that they thought they had the only X-Men property in other media but “Mutant X” apparently wasn’t considered an X-franchise title and so it was optioned for a TV series running at the same time as the new movies. (That’s it in a nutshell.)
Now, the company behind Mutant X is suing Marvel because fighting the lawsuit by deep-pocketed Fox has now made “Mutant X” a loss for them. In addition to the legal costs, they’ve had to alter the show so that it bears less resemblence to X-Men and that has hurt the viability of the property in profits and licensing.
It certainly sounds like a good argument to me, assuming that they didn’t go into this with the intention of doing a ripoff show siphoning off the interest in the X-Men movies. But I suppose that was what the whole earlier lawsuit was about!