How Does the Common Interest Doctrine Work in the Intellectual Property Context?

November 9, 2022

The common interest doctrine sometimes prevents what would be a waiver when separately represented clients disclose privileged communications to each other. But the doctrine normally requires an identical legal interest, not just a shared financial interest in a litigation’s outcome. Two recent intellectual property cases highlight courts’ widely varying approaches to the common interest doctrine protection.

In BBAM Aircraft Management LP v. Babcock & Brown LLC, Case No. 3:20-cv-1056 (OAW), 2022 U.S. Dist. LEXIS 154791 (D. Conn. Aug. 29, 2022), the court took an expansive view of the common interest doctrine. Among other things, it found the doctrine available even to a non-party to the litigation. The court also found that the common interest doctrine could avoid a waiver “even if no attorney is involved” in the communication. Id. at *9. Finally, the court held that “the relationship between a trademark licensor and its licensee necessitates a common interest in the protection of the mark from infringing uses such that sharing attorney advice does not result in the waiver of privilege.” Id. at *11-12. But just a few days earlier, the court in KPH Healthcare Services, Inc. v. Mylan, N.V., Case No. 2:20-cv-02065-DDC-TJJ, 2022 U.S. Dist. LEXIS 151439 (D. Kan. Aug. 23, 2022) applied a more demanding standard when assessing communications between Mylan and Pfizer involving patents for the commonly used EpiPen. Explicitly rejecting an earlier case requiring only “substantially identical” legal interests, the court demanded “identical” legal interests. Id. at *21-22. The court acknowledged that Mylan and Pfizer had “operative agreements” relating to the EpiPen patent before Pfizer transferred the patents to Mylan in July 2013. Id. at *22-23. But the court “conclude[ed] that while Mylan and Pfizer had a shared desire to prevail in any potential litigation regarding the patents before July 2013, they did not have an identical legal interest until the transfer was effectuated.” Id. at *23. Oddly, the court did not assess any work product claims for pre-July 2013 withheld documents.

Some lawyers erroneously think that a court will automatically honor their contractual non-waiver agreement asserting the common interest doctrine. And such contracting clients normally begin to immediately share privileged communications based on such agreements. But even well-known companies represented by sophisticated lawyers frequently lose the common interest argument, by which time it is too late to have avoided privilege waiver.