privy

noun | \ ˈpri-vē \

1. : one having privity; especially : one who acquires an interest in the subject matter (as property) of prior or pending litigation and is bound by the judgment as if he or she were a party to the action : one who acquires an interest in the subject matter (as property) of prior or pending litigation and is bound by the judgment as if he or she were a party to the action