Rule 502, where are you?

Anyone remember “Car 54, Where Are You?” Well, that’s probably another story. On where Federal Rule of Evidence Rule 502 is, Hangley Aronchick’s John S. Summers and Michael D. Gadarian find it with two flags: (1) The rule flips the current presumption on subject matter waivers on its head and (2) it falls short of providing guidance when “fairness” requires a subject matter waiver.