N.Y. C.P.L.R. 901 — Prerequisites to a class action

§ 901. Prerequisites to a class action. a. One or more members of a class may sue or be sued as representative parties on behalf of all if:

1. the class is so numerous that joinder of all members, whether otherwise required or permitted, is impracticable;

2. there are questions of law or fact common to the class which predominate over any questions affecting only individual members;

3. the claims or defenses of the representative parties are typical of the claims or defenses of the class;

4. the representative parties will fairly and adequately protect the interests of the class; and

5. a class action is superior to other available methods for the fair and efficient adjudication of the controversy.

b. Unless a statute creating or imposing a penalty, or a minimum measure of recovery specifically authorizes the recovery thereof in a class action, an action to recover a penalty, or minimum measure of recovery created or imposed by statute may not be maintained as a class action.