Rule 21.Misjoinder and nonjoinder of parties
Group IV: Parties · Last amended March 1, 2019 · Last verified July 14, 2026
Full Text of Rule 21
Amendment History
Amended eff. 3-1-19.
Plain-English Summary
Lawsuits sometimes end up with a party who should not be there, or missing a party who should be. Rule 21 keeps that kind of mistake from sinking an otherwise good case. Misjoinder, meaning someone was included who does not belong, is never by itself grounds to dismiss the action. Instead, the court fixes the lineup.
That fix can happen anytime, whether a party asks for it or the court raises it on its own, and the court sets whatever conditions are fair given the circumstances. The court can add a party who is missing, drop one who should not be there, or split off, or sever, a particular claim against a party so it proceeds as its own case. The goal is to keep the litigation moving on the merits rather than derailing it over who happens to be named in the caption.
Frequently Asked Questions
Can a case be dismissed just because the wrong person was named as a party?
No. Rule 21 says misjoinder of parties is never grounds for dismissing an action. The court addresses the problem by adjusting who is in the case, not by throwing the whole case out.
Who can ask the court to add or drop a party?
Any party can file a motion asking the court to do so, and the court can also act on its own without waiting for a request.
What does it mean to "sever" a claim?
Severing a claim means the court splits it off from the rest of the case so it proceeds separately, often as its own lawsuit, rather than continuing to be litigated alongside the other claims.
Is there a deadline for fixing a misjoinder problem?
No. The rule allows the court to add or drop a party at any time during the case, on whatever terms are just under the circumstances.
How is misjoinder different from failing to join a required party?
Misjoinder means someone was improperly included; this rule lets the court drop that party. A required party who is missing from the case is addressed by a different rule, which governs when someone must be joined and what happens if they cannot be.