Board Thread:General Discussion/@comment-3048593-20130509225000/@comment-3419446-20130516055420

Another criterion: When characters from an alternate earth are interacting with Earth-616 characters, it is probably safe to assume that the respective alternate Captain Britains (or similarly named folks) are part of the CBC. Still, as long as they are not explicitly shown as CBC members in gatherings, assistances and the like, I would count them only as presumed members.