Main character = Chris, Jill, Leon (the ones that carry the series and have many adventures)
Secondary protagonist = Rebecca, Billy, Sheva (important enough to lead in a numbered title, but irrelevant to the series as a whole)
I used to think Claire was a main, but she hasn't been in the main games for over a decade, was the only one of the four not to have a new story in the Chronicles games and her small appearance in Degeneration felt like an attempt to write her out of the series. Is it time for her to get demoted to secondary status?
She IS a main character, always was, always will be, RE is not RE without her, so what if she didn't have her own game in long time? Did you know that before RE5 chris only appeared in 2 games? And he was considered to be the main character of RE despite that, so yea claire is main character of RE along with chris, leon and jill.