OFFENSIVE-USE WAIVER
offensive-use waiver.An exemption from the attorney–client privilege, whereby a litigant is considered to have waived the privilege by seeking affirmative relief, if the claim relies on privileged information that would be outcome-determinative and that the opposing party has no other way to obtain. Cf. AT-ISSUE WAIVER R. [Cases: Witnesses 219(3).]
[Blacks Law 8th]