Yes. In employment cases, the plaintiffs must prove that they meet one of two additional rules under Federal Rule 23(b), either that: The party opposing the certification of a class action has acted or refused to act on grounds generally applicable to the class, making final injunctive or corresponding declaratory relief appropriate for the class as a whole (discussed in question 10); or, The questions of law or fact common to the members of the class predominate over any questions affecting only individual members (discussed in question 11); and, That it be found that a class action is superior to other available methods for the fair and efficient determination of the controversy (discussed in question 12).