Because Fox dont want to give that license back and Marvel is being a bunch of petty bytches about this shyt...Remember as long as fox keeps making films with x-men characters and or mutants they wont revert back to marvel unless it's under extreme circumstances and even if the x-men movies do suck they are still a box office draw the shyt prints money so Fox is reluctant to give back them rights I believe...
how is that petty? so they advertise and put out merchandise that fox gains a high portion of? i love the x-men too, but it is what it is. and its not like comics is going through some sort or renaissance that he x-men are missing out on. its garbage across the board
Remember as long as fox keeps making films with x-men characters and or mutants they wont revert back to marvel unless it's under extreme circumstances and even if the x-men movies do suck they are still a box office draw the shyt prints money so Fox is reluctant to give back them rights I believe...

This is hurting the fans who love these characters and books, it's hurting us... 

X-Men held a stranglehold on us because of their diverse looks and abilities. Marvel gave the rights away because they were going bankrupt so Fox cashed in and made major bank. It's not their fault fans have been enjoying it in their own right. Instead of trying to create a deal and be amicable about it they cancelled FF books, killed off their characters pretty much, now are killing off the X-Men. An Inhuman movie was ONLY happening because Perlmutter was Feiges boss at one point. Once Bob Igor owner of Disney said report to him that Inhumans movie was scrapped as Feige is in control now for the MCU. Spider-Man is only at Marvel because fans weren't feeling the direction. If Am Spider-Man 2 made a billie we'd have Spider-Man 3 by now. Marvel is trying to force Fox to lose money in X-men by killing them in the comics and pushing Inhumans. Fox only has movies and that Legion show as their only means of marketing for them at this point. 