N.Y. CVP Law § 902

§ 902. Order allowing class action. Within sixty days after the time\nto serve a responsive pleading has expired for all persons named as\ndefendants in an action brought as a class action, the plaintiff shall\nmove for an order to determine whether it is to be so maintained. An\norder under this section may be conditional, and may be altered or\namended before the decision on the merits on the court's own motion or\non motion of the parties. The action may be maintained as a class action\nonly if the court finds that the prerequisites under section 901 have\nbeen satisfied. Among the matters which the court shall consider in\ndetermining whether the action may proceed as a class action are:\n 1. the interest of members of the class in individually controlling\nthe prosecution or defense of separate actions;\n 2. the impracticability or inefficiency of prosecuting or defending\nseparate actions;\n 3. the extent and nature of any litigation concerning the controversy\nalready commenced by or against members of the class;\n 4. the desirability or undesirability of concentrating the litigation\nof the claim in the particular forum;\n 5. the difficulties likely to be encountered in the management of a\nclass action.\n