Rule 23, Federal Rules of Civil Procedure

(a) Prerequisites to a Class Action. One or more members of a class may sue or be sued as representative parties on behalf of all only if (1) the class is so numerous that joiner of all members is impracticable, (2) there are questions of law or fact common to the class, (3) the claims or defenses of the representative parties are typical of the claims or defenses of the class, and (4) the representative parties will fairly and adequately protect the interests of the class.

(b) Class Actions Maintainable. An action may be maintained as a class action if the prerequisites of subdivision (a) are satisfied, and in addition:

(1) the prosecution of separate actions by or against individual members of the class would create a risk of

(2) the party opposing the class has acted or refused to act on grounds generally applicable to the class, thereby making appropriate final injunctive relief or corresponding declaratory relief with respect to the class as a whole; or

(3) the court finds that the questions of law or fact common to the members of the class predominate over any questions affecting only individual members, and that a class action is superior to other available methods for the fair and efficient adjudication of the controversy. The matters pertinent to the findings include: (A) the interest of members of the class in individually controlling the prosecution or defense of separate actions; (B) the extent and nature of any litigation concerning the controversy already commenced by or against members of the class; (C) the desirability or undesirability of concentrating the litigation of the claims in the particular forum; (D) the difficulties likely to be encountered in the management of a class action.

(1) As soon as practicable after the commencement of an action brought as a class action, the court shall determine by order whether it is to be so maintained. An order under this subdivision may be conditional, and may be altered or amended before the decision on the merits.

(2) In any class action maintained under subdivision (b)(3), the court shall direct to the members of the class the best notice practicable under the circumstances, including individual notice to all members who can be identified through reasonable effort. The notice shall advise each member that (A) the court will exclude the member from the class if the member so requests by a specified date; (B) the judgment, whether favorable or not, will include all members who do not request exclusion; and (C) any member who does not request exclusion may, if the member desires, enter an appearance through counsel.

(3) The judgment in an action maintained as a class action under subdivision (b)(1) or (b)(2), whether or not favorable to the class, shall include and describe those whom the court finds to be members of the class. The judgment in an action maintained as a class action under subdivision (b)(3), whether or not favorable to the class, shall include and specify or describe those to whom the notice provided in subdivision (c)(2) was directed, and who have not requested exclusion, and whom the court finds to be members of the class.

(4) When appropriate (A) an action may be brought or maintained as a class action with respect to particular issues, or (B) a class may be divided into subclasses and each subclass treated as a class, and the provisions of this rule shall then be construed and applied accordingly.

(d) Orders in Conduct of Actions. In the conduct of actions to which this rule applies, the court may make appropriate orders: (1) determining the course of proceedings or prescribing measures to prevent undue repetition or complication in the presentation of evidence or argument; (2) requiring, for the protection of the members of the class or otherwise for the fair conduct of the action, that notice be given in such manner as the court may direct to some or all of the members of any step in the action, or of the proposed extent of the judgment, or of the opportunity of members to signify whether they consider the representation fair and adequate, to intervene and present claims or defenses, or otherwise to come into the action; (3) imposing conditions on the representative parties or on interveners; (4) requiring that the pleadings be amended to eliminate there from allegations as to representation of absent persons, and that the action proceed accordingly; (5) dealing with similar procedural matters. The orders may be combined with an order under Rule 16, and may be altered or amended as may be desirable from time to time.

(e) Dismissal or Compromise. A class action shall not be dismissed or compromised without the approval of the court, and notice of the proposed dismissal or compromise shall be given to all members of the class in such manner as the court directs.

(f) Appeals. A court of appeals may in its discretion permit an appeal from an order of a district court granting or denying class action certification under this rule if application is made to it within ten days after entry of the order. An appeal does not stay proceedings in the district court unless the district judge or the court of appeals so orders.

Rule 23.1 Derivative Actions by Shareholders. In a derivative action brought by one or more shareholders or members to enforce a right of a corporation or of an unincorporated association, the corporation or association having failed to enforce a right which may properly be asserted by it, the complaint shall be verified and shall allege (1) that the plaintiff was a shareholder or member at the time of the transaction of which the plaintiff complains or that the plaintiff's share or membership thereafter devolved on the plaintiff by operation of law, and (2) that the action is not a collusive one to confer jurisdiction on a court of the United States which it would not otherwise have. The complaint shall also allege with particularity the efforts, if any, made by the plaintiff to obtain the action the plaintiff desires from the directors or comparable authority and, if necessary, from the shareholders or members, and the reasons for the plaintiff's failure to obtain the action or for not making the effort. The derivative action may not be maintained if it appears that the plaintiff does not fairly and adequately represent the interests of the shareholders or members similarly situated in enforcing the right of the corporation or association. The action shall not be dismissed or compromised without the approval of the court, and notice of the proposed dismissal or compromise shall be given to shareholders or members in such manner as the court directs.

Rule 23.2 Actions Relating to Unincorporated Associations. An action brought by or against the members of an unincorporated association as a class by naming certain members as representative parties may be maintained only if it appears that the representative parties will fairly and adequately protect the interests of the association and its members. In the conduct of the action the court may make appropriate orders corresponding with those described in Rule 23(d), and the procedure for dismissal or compromise of the action shall correspond with that provided in Rule 23(e)