term:

Privy

privy n

pl: priv·ies
[Anglo-French privé, from Old French, intimate, confidant, from privé intimate, familiar, from Latin privatus private]
: one having privity
;esp
: 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

Source: Merriam-Webster's Dictionary of Law ©1996. Merriam-Webster, Incorporated. Published under license with Merriam-Webster, Incorporated.