The federal courts have recognized that waiver by disclosure may occur if a litigant discloses work-product materials to an adversary, and have indicated that such disclosure to one adversary may-although will not invariably-trigger an implied waiver of the immunity vis-a-vis other adversaries. See, ie.g.,
In re Steinhardt Partners, LP., 9 F.3d 230, 235-36 (2d Cir.1993); In re Cardinal Health, Inc. Sec. Litig., 2007 WL 495150, at *9 (S.D.N.Y. Jan.26, 2007). That principle of waiver has been expanded to encompass waiver by disclosure to non-adversaries in circumstances that make it likely that the erstwhile protected materials will be revealed to an adversary. See, e.g.,
Seven Hanover Assocs., LLC v. Jones Lang LaSalle Americas, Inc., 2005 WL 3358597, at *1 n. 3 (S.D.N.Y. Dec.7, 2005); In re Gulf Oil/Cities Serv. Tender Offer Litig., 1990 WL 108352, at *4 (S.D.N.Y. July 20, 1990). By the same token, “disclosure simply to another person who has an interest in the information but who is not reasonably viewed as a conduit to a potential adversary will not be deemed a waiver” of the rule. In re Gulf Oil, 1990 WL 108352, at *4 (citing cases).