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Rule 21.Misjoinder and Non-Joinder of Parties

Effective July 1, 1974 · Last verified June 26, 2026

In one sentenceRule 21 says a case is never dismissed merely because parties are wrongly joined or left out; the court instead drops, adds, or severs parties as justice requires.

Full Text of Rule 21

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Misjoinder of parties is not ground for dismissal of an action. Parties may be dropped or added by order of the court on motion of any party or of its own initiative, after hearing, at any stage of the action and on such terms as are just. Any claim against a party may be severed and proceeded with separately.
End

Rule History

Effective July 1, 1974.

Reporter’s Notes

(1973)

Rule 21 embodies prior law: G.L. c. 231, § 4A; §§ 51-54, and adds to Federal Rule 21 the requirement of a hearing before parties may be dropped or added.

Plain-English Summary

Rule 21 keeps a party mistake from ending a case. Misjoinder—joining the wrong party—is not a ground for dismissal. Instead, at any stage and on just terms, the court may drop or add parties on a party's motion or on its own after a hearing, and it may sever any claim against a party to proceed separately. The rule turns what used to be fatal pleading errors into adjustments the court can make as the case develops.

Frequently Asked Questions

Can a case be dismissed because the wrong party was named?

No. Rule 21 provides that misjoinder of parties is not a ground for dismissal. The court drops, adds, or severs parties as justice requires.

How are parties added or dropped?

By order of the court, on motion of any party or on the court's own initiative after a hearing, at any stage of the action and on terms that are just.

Source & verification. Rule text, Rule History, and Reporter’s Notes reproduced verbatim from the Massachusetts Rules of Civil Procedure as published by the Massachusetts Trial Court Law Libraries. Promulgated by the Supreme Judicial Court of Massachusetts. Last verified June 26, 2026. · Official text
Also known as: misjoindernon-joinderdropping a partyadding a partyseverance