Supreme Court Rules

First Adopted: April 21, 1972

Most Recently Effective: January 01, 1994

Rule 52 | Rules of Civil Procedure | Rules Governing Civil Procedure in the Circuit Courts | Parties

52.12 | Intervention

(a) Intervention of Right. Upon timely application anyone shall be permitted to intervene in an action: 

(1) when a statute of this state confers an unconditional right to intervene or 

(2) when the applicant claims an interest relating to the property or transaction that is the subject of the action and the applicant is so situated that the disposition of the action may as a practical matter impair or impede the applicant's ability to protect that interest, unless the applicant's interest is adequately represented by existing parties.

(b) Permissive Intervention. Upon timely application anyone may be permitted to intervene in an action: 

(1) when a statute of this state confers a conditional right to intervene; or 

(2) when an applicant's claim or defense and the main action have a question of law or fact in common; or 

(3) when the validity of a statute, regulation or constitutional provision of this state, or an ordinance or regulation of a governmental subdivision thereof, affecting the public interest, is drawn in question in any action to which the state or governmental subdivision or an officer, agency or employee thereof is not a party, the court may in its discretion notify the chief legal officer of the state or governmental subdivision thereof, and the state or governmental subdivision may in the discretion of the court be permitted to intervene, upon proper application.

(c) Procedure. A person desiring to intervene shall serve a motion upon all parties affected thereby. The motion shall state the grounds therefor, and shall be accompanied by a pleading setting forth the claim or defense for which intervention is sought. The same procedure shall be followed when a statute of this state gives a right to intervene.

Committee Note – 1974

Paragraph (a) is the same as Rule 24(a) of the Federal Rules of Civil Procedure except for the reference to Missouri statutes instead of statutes of the United States.

Paragraphs (b) and (c) are substantially the same as prior Rule 52.11(b) and (c).



(Adopted April 21, 1972, eff. Dec. 1, 1972. Amended September 28, 1993, effective January 1, 1994.)
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