RJ

I. BACKGROUND

20 On December 15, 2022, shortly before the close of fact discovery, plaintiffs learned that 21 defendants entered into a common interest agreement with United, a defendant in the LD matter. 22 Dkt. No. 136 at 1. Plaintiffs say that they immediately requested “the agreement itself, all 23 correspondence, and other documents shared between the parties.” Id. Defendants have agreed to 24 produce their written “joint defense agreement” with United, but decline to produce any other 25 materials. Id. at 4. 26

II. DISCUSSION

1 The voluntary disclosure of a privileged or protected document or information to a third 2 party ordinarily waives that privilege or protection. United States v. Ruehle, 583 F.3d 600, 612 3 (9th Cir. 2009); Weil v. Inv./Indicators, Research & Mgmt., Inc., 647 F.2d 18, 25 (9th Cir. 1981). 4 The “common interest” or “joint defense” doctrine is an exception to ordinary waiver rules that 5 applies when parties represented by separate counsel communicate in confidence about a matter of 6 common legal interest, in furtherance of that common legal interest. See In re Pac. Pictures Corp., 7 679 F.3d 1121, 1129 (9th Cir. 2012). The doctrine does…