...s". They SOLD, to stave off their impending bankruptcy, the movie rights to some of their characters to studios capable of making big-budget blockbuster movies which would, in turn, (hopefully) generate more comic book sales. Replacements aren't the issue here. Yes, Inhumans (not created for the MCU, btw, they were created in the pages of the Fantastic Four books 50 years ago) are substituting for mutants in the context of the MCU, but not for specific characters. The FF movie's (which I quite enjoyed) dismal box office performance in no way "reverts" the rights back to Marvel, but it may hopefully provide Marvel leverage in negotiations just as ASM2's crappy reception did. I hate the idea of "rebooting" the FF again already, but given the context of the MCU and their current schedule, it'll likely be 5 or 6 years before we would see Marvel's original family of adventurers in an MCU film, should the rights issues get sorted. Excelsior!