Rule 41.Dismissal of Actions.

A plaintiff can dismiss voluntarily and without a court order either by filing a notice of dismissal before the return date set under Rule 12(a) and before the defendant answers or moves for summary judgment, or by filing a stipulation signed by every party who has appeared, following the format Rule 41.1 requires. That dismissal is without prejudice unless it says otherwise, with one exception: a second dismissal of the same claim, after the plaintiff already dismissed it once before in any U.S. court, counts as a decision on the merits. Once those windows close, the plaintiff needs a court order to dismiss, and if a defendant has already pleaded a counterclaim, the court won't dismiss the plaintiff's claim over the defendant's objection unless the counterclaim can still be independently adjudicated.

The court can also dismiss involuntarily, on a defendant's motion or on its own initiative, when the plaintiff fails to prosecute the case or comply with the rules or a court order; a dismissal the court orders on its own must come with written notice, and can be set aside for good cause on a timely motion. Except for dismissals for lack of jurisdiction, improper venue, or failure to join a required party, these dismissals count as decisions on the merits unless the court says otherwise. The same dismissal rules apply to counterclaims, cross-claims, and third-party claims, and if a plaintiff who already dismissed one action brings the same claim again, the court can order the plaintiff to pay the costs of the earlier action and can pause the new case until that happens.