(a) Necessary Joinder. Subject to the provisions of subdivision (b) of this rule, persons having a joint interest which is not also a several interest shall be made parties and be joined on the same side as plaintiffs or defendants. When a person who should join as a plaintiff refuses to do so, the person may be made a defendant. (b) Effect of Failure to Join. When persons who are not indispensable, but who ought to be parties if complete relief is to be accorded between those already parties, have not been made parties and are subject to the jurisdiction of the court, the court shall order them summoned to appear in the action. The court in its discretion may proceed in the action without making such persons parties, if the court’s jurisdiction over them can be acquired only by their consent or voluntary appearance; but the judgment rendered therein does not affect the rights or liabilities of absent persons. (c) Effect of Failure to Join: Names of Omitted Persons and Reasons for Nonjoinder to Be Pleaded. In any pleading in which relief is asked, the pleader shall set forth the names, if known to the pleader, of persons who ought to be parties if complete relief is to be accorded between those already parties, but who are not joined, and shall state why they are omitted.
