Marvel Studios has not yet needed an R rating to make its shared universe of superhero films work. Just two months ago, studio president Kevin Feige seemed to make that clear in an interview to promote Guardians of the Galaxy Vol. 2, praising R-rated blockbusters Logan and Deadpool as films that did well not because of adult content but because of an individual voice.

“My takeaway from both of those films is not the R rating; it’s the risk they took, the chances they took, the creative boundaries that they pushed,” he told The Hollywood Reporter. “That should be the takeaway for everyone.”

Since then, Guardians has become the massive hit we all expected it to be, anticipation has continued to build for Thor: Ragnarok and next year’s Black Panther is riding a huge wave of buzz after its trailer debut last week. Nothing has changed for Marvel Studios, except Feige’s public stance on R-rated films under his banner.

“Currently we don’t work on R-Rated movies,” he told AlloCine this week. “It’s not out of the question but currently, no.”

So, in two months Feige’s response to the inevitable R-rated interview question has shifted from “that’s not as important as people think” to “we haven’t ruled it out.” This is by no means a seismic shift. If anything, it’s Feige adopting a more PR-friendly, keep your options open tone when discussing the topic. The change is interesting, though, because it does point us to an inevitable question of the shared universe age: At what point does the reigning shared universe powerhouse stop leading and start following.

Marvel’s success with PG-13 films shows no sign of flagging, particularly as the studio heads into its two-part, universe-uniting Avengers: Infinity War project. That film, easily one of the biggest blockbuster endeavors of all times, is poised to set a new standard for scope in superhero cinema. But what happens after that? When you’ve built individual franchises into megafranchises and then built megafranchises into ultrafranchises, what’s next?

The answer might be something similar to what Fox has done in the last two years. Though the studio hasn’t abandoned its X-Men team-up series by any means, it has seen tremendous success giving more adult-oriented characters a more intimate platform. Now Fox is hoping to expand the reach of those adults characters with the R-rated team flick X-Force, while Sony hopes to reinvigorate its Spider-Man rights (separate from what Marvel’s doing) with a potentially R-rated Venom film. Even Warner Bros. has flirted with more violent territory thanks to the R-rated home media cut of Batman v Superman: Dawn of Justice. It’s not hard to see that studio expanding its own horizons beyond PG-13 with fan-favorite characters like Lobo or even Swamp Thing.

So that leaves Marvel. To be fair, the studio’s already flirted with content in the style of R-rated cinema thanks to its street-level Netflix shows, which are technically in the same universe as the films but enjoy a large amount of independence. Those projects cater to a different need, though. The movies are about butts in seats and toys on shelves as much as they’re about superhero universe building. This is Disney we’re talking about, after all.

Still, it’s hard to imagine there’s not an executive sitting at the House of Mouse right now, looking at Deadpool’s box office returns with dollar signs in his eyes. R ratings at Marvel might not happen anytime soon but it’s hard to imagine them never happening. Feige and company could simply resurrect the old Marvel Knights banner that was used for things like Punisher: War Zone and slap it on a flick starring Moon Knight or Nextwave or even Karnak. Eventually Marvel will find itself in a place where it needs to adapt or die in a changing superhero cinematic market, something Fox has already done with great success. The biggest question is likely not if but when.