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 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.
Rule 21.Misjoinder and nonjoinder of parties
Part IV: Parties · Not amended since adoption on record · Last verified July 28, 2026
In one sentenceRule 21 states that misjoining parties is never grounds to dismiss a Delaware action, and lets the court add or drop parties, or sever a claim against a party for separate proceedings, on motion or on its own initiative at any stage of the case.
Full Text of Rule 21
Plain-English Summary
Rule 21 opens with a flat statement: misjoinder of parties is not ground for dismissal of an action. A case doesn't get thrown out because the wrong combination of parties ended up in it.
Instead, the court has ongoing authority to fix the problem. Parties may be dropped or added by court order, on motion of any party or on the court's own initiative, at any stage of the action, and on whatever terms are just. That authority isn't limited to the pleading stage — it runs throughout the life of the case.
Rule 21 also allows severance: any claim against a party may be severed and proceeded with separately. That gives the court a tool to untangle a case where one claim or one party doesn't belong with the rest, without dismissing anything.
Frequently Asked Questions
Can my Delaware case be dismissed because I joined the wrong parties?
No. Rule 21 states directly that misjoinder of parties is not ground for dismissal of an action.
Can the court add or drop parties without anyone filing a motion?
Yes. Rule 21 allows the court to add or drop parties on its own initiative, not only on motion of a party, at any stage of the action.
Is there a deadline for fixing a misjoinder or nonjoinder problem?
Rule 21 doesn't set one. It allows parties to be added or dropped at any stage of the action, on terms that are just.
What does it mean to sever a claim under Rule 21?
It means the court proceeds with a claim against a particular party as a separate matter rather than dismissing it or keeping it bundled with the rest of the action.
Source & verification. Rule text is reproduced verbatim from the
Delaware Rules of Civil Procedure for the Superior Court, adopted by the
Superior Court of the State of Delaware. Last verified July 28, 2026.
· Official source
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