Plaintiffs who opt-in during a collective action under the FLSA must disclose their computation of damages under Rule 26(a), just as any other plaintiff must, or risk exclusion of such evidence at trial. Hoffman v. Construction Protective Services, Inc. (9th Cir. 2008) 541 F.3d 1175.
The trial court certified an FLSA collective action, but there was no pre-trial disclosure of damage calculations for the individual opt-in plaintiffs. At trial, the court excluded all evidence of damage for the opt-ins, but allowed evidence regarding claims of the named plaintiffs. The class appealed the exclusion of damages evidence and an award of attorney fees. The Ninth Circuit affirmed.