12.21.2 A plaintiff to whom an interim payment has been made, whether voluntarily or under an order made under rule 3.56.3 or 3.56.4, may discontinue the proceeding only with the written consent of the party who made the payment or with the leave of the court.
12.21.3 A plaintiff may discontinue a proceeding in which there is more than 1 plaintiff only with the consent of every other plaintiff or with the leave of the court. If the plaintiff files a notice of discontinuance under rule 12.20.2, the consent of every other plaintiff must be in writing.
12.21.4 If there is more than 1 defendant in a proceeding, a plaintiff may discontinue a proceeding against a particular defendant only with the consent of every other defendant or with the leave of the court. If the plaintiff files a notice of discontinuance under rule 12.20.2, the consent of every other defendant must be in writing.