In Diaz v. First American Home Buyers Protection Corp., ___ F.3d ___ (9th Cir. Oct. 4, 2013), the Ninth Circuit held that "an unaccepted Rule 68 offer that would fully satisfy a plaintiff’s claim is insufficient to render the claim moot." Slip op. at 3.
This shuts the door to "picking off" the class representative—a door some believed was left open by Genesis Healthcare Corp. v. Symczyk, 133 S. Ct. 1523 (2013). As the Diaz court observed, the Supreme Court did not decide the issue in that case. Slip op. at 8 (citing Genesis Healthcare, 133 S. Ct. at 1528-29). The substantive analysis in Diaz relies heavily on Justice Kagan's dissent, however, which did address it. Diaz, slip op. at 10-15.