Common interest agreements and joint representations share many characteristics. Both types of arrangements involve lawyers engaging in protected communications with multiple clients. But they are structurally distinct. In common interest agreements, separately represented clients cooperate in a common legal strategy. In a joint representation, the same lawyers represent several clients on the same matter. As long as everything rolls along smoothly, the structural difference has few privilege consequences. But adversity reveals a key privilege distinction.

In DePuy Orthopaedics, Inc. v. Orthopaedic Hospital, Cause No. 3:12-cv-299-JVB-MGG, 2016 U.S. Dist. LEXIS 166537 (N.D. Ind. Dec. 1, 2016), plaintiff DePuy and defendant Hospital had worked together on patent prosecutions - but later become litigation adversaries. DePuy resisted the Hospital's attempt to discover communications to and from DePuy's in-house counsel. The in-house counsel claimed that DePuy and the Hospital had only entered into a common interest agreement - noting that O'Melveny & Myers had acted as patent "prosecution counsel" on behalf of both companies. In contrast, the Hospital "claim[ed] that DePuy's in-house counsel jointly represented both parties." The court recited facts that could have proven either a common interest agreement or a joint representation: DePuy and the Hospital shared confidential information and cooperated on a common legal strategy; DePuy's in-house counsel communicated with and gave direction to O'Melveny, etc. But the court ultimately concluded that DePuy's in-house counsel had jointly represented DePuy and the Hospital -- rather than represented just DePuy in a common interest arrangement with the separately represented Hospital.

Given the privilege implication similarities between a common interest agreement and a joint representation, one might wonder why DePuy's in-house counsel argued so strenuously against the latter. Next week's Privilege Point will explain the court's key reason for finding such a joint representation, and its frightening implication.