(a) Persons to Be Joined if Feasible. A person shall be joined in the action if: (1) in the person’s absence complete relief cannot be accorded among those already parties, or (2) the person claims an interest relating to the subject of the action and is so situated that the disposition of the action in the person’s absence may: (i) as a practical matter impair or impede the person’s ability to protect that interest or (ii) leave any of the persons already parties subject to a substantial risk of incurring double, multiple, or otherwise inconsistent obligations by reason of the claimed interest. If the person has not been joined, the court shall order that the person be made a party. If the person should join as a plaintiff but refuses to do so, the person may be made a defendant.
Rule 52.04.Joinder of Persons Needed for Just Adjudication.
Part I · Rule 52: Parties · Last amended January 1, 1994 · Last verified July 22, 2026
In one sentenceRule 52.04 requires a court to join any absent person whose presence is needed for complete relief or to protect that person's own interest, and it directs the court to weigh several factors before proceeding without that person or dismissing the case entirely.
Full Text of Rule 52.04
(b) Determination by Court Whenever Joinder Not Feasible. If a person as described in Rule 52.04(a)(1) or Rule 52.04(a)(2) cannot be made a party, the court shall determine whether in equity and good conscience the action should proceed among the parties before it or should be dismissed, the absent party being thus regarded as indispensable. The factors to be considered by the court include: (i) to what extent a judgment rendered in the person’s absence might be prejudicial to that person or those already parties; (ii) the extent to which by protective provisions in the judgment, by the shaping of relief, or other measures, the prejudice can be lessened or avoided; (iii) whether a judgment rendered in the person’s absence will be adequate; and (iv) whether the plaintiff will have an adequate remedy if the action is dismissed for nonjoinder.
(c) Pleading Reasons for Nonjoinder. A pleading asserting a claim for relief shall state the names, if known to the pleader, of any persons as described in subdivisions (a) (1)-(2) hereof who are not joined, and the reasons why they are not joined.
(d) Exception of Class Actions. This rule is subject to the provisions of Rule 52.08.
Amendment History
Adopted April 21, 1972, eff. Dec. 1, 1972. Amended Sept. 28, 1993, eff. Jan. 1, 1994.
Official Comment
This is the same as Rule 19 of the Federal Rules of Civil Procedure with references to jurisdiction and venue eliminated.
Plain-English Summary
Rule 52.04 identifies people who need to be in a case for it to be resolved properly. A person must be joined if, without them, the court cannot give complete relief among the parties already in the case, or if the person claims an interest in the subject of the action and leaving them out could, as a practical matter, impair their ability to protect that interest, or leave the existing parties exposed to double, multiple, or inconsistent obligations because of the absent person's claim. Once the court identifies such a person, it orders that they be joined; if the person belongs on the plaintiff's side but will not join voluntarily, the court can instead make that person a defendant.
Sometimes joinder is not possible — the person may be beyond the court's reach, for example. In that situation, Rule 52.04(b) asks the court to decide, in equity and good conscience, whether the case should proceed among the parties already before it or be dismissed, treating the absent person as indispensable. The court weighs how much a judgment reached without that person might prejudice the absent person or the existing parties, whether protective measures in the judgment could lessen that prejudice, whether a judgment rendered without the absent person would be adequate, and whether the plaintiff would have an adequate remedy if the case were dismissed instead.
A pleading that asserts a claim must name any such person known to the pleader who has not been joined and explain why. This forces the issue onto the record early instead of letting it surface later in the litigation. Rule 52.04 does not govern class actions, which follow their own joinder framework under Rule 52.08.
Frequently Asked Questions
What makes a person “needed for just adjudication” under Rule 52.04?
Two situations trigger it: complete relief cannot be given among the existing parties without that person, or the person claims an interest in the case's subject matter and proceeding without them could impair that interest or expose the existing parties to inconsistent obligations.
What happens if a necessary party cannot be brought into the case?
The court decides, in equity and good conscience, whether the case should proceed among the parties already before it or be dismissed, treating the absent person as indispensable, after weighing the factors Rule 52.04(b) lists.
What factors does the court weigh before dismissing for nonjoinder?
Whether a judgment rendered without the absent person would prejudice that person or the existing parties, whether protective measures could lessen the prejudice, whether a judgment without the absent person would be adequate, and whether the plaintiff would have an adequate remedy if the case were dismissed.
Does a plaintiff have to explain why someone was left out of the case?
Yes. A pleading asserting a claim must name any person described in Rule 52.04(a) who is known to the pleader but not joined, and state the reasons for not joining that person.
How does Rule 52.04 relate to class actions?
Rule 52.04 says expressly that it is subject to Rule 52.08, so class actions follow their own certification and joinder framework instead of the individual-party analysis this rule sets out.
Can a person who should be a plaintiff be forced into the case as a defendant instead?
Yes. If a person should join the action as a plaintiff but refuses to do so, Rule 52.04(a) allows the court to make that person a defendant instead.
Source & verification. Rule text and amendment history are
reproduced verbatim from the Missouri State & Federal Court Rules, adopted by the
Supreme Court of Missouri. Last verified July 22, 2026. ·
Official source
Also known as: necessary partiesindispensable partiesjoinder for just adjudicationcompulsory joinderrequired party joinder