The Hollywood actor previously credited the veteran guitarist with inspiring his flamboyant Jack Sparrow character, and Richards made two cameos playing Depp's onscreen swashbuckling father Captain Teague in the adventure films.
Now the rocker reveals he may be heading back to the big screen as Depp prepares to shoot a fifth installment.
Richards tells Bbc 6 Music, "I spoke to Johnny a couple of weeks ago and he said, 'Are you up for another one?' I can leave it at that because I know no more. But I do have the costume! (It helps because) some kids who don't know nothing (sic) about the Rolling Stones go, 'There's Johnny Depp's dad! There's Captain Teague, arrgh!'"