Every civil action shall be prosecuted in the name of the real party in interest, but an executor, administrator, guardian, trustee of an express trust, a party with whom or in whose name a contract has been made for the benefit of another and a party authorized by statute may sue in their own names in such representative capacity without joining the party for whose benefit the action is brought. When a statute so provides, a civil action for the use or benefit of another shall be brought in the name of the State of Missouri.
Rule 52.01.Civil Actions--In Whose Name Prosecuted--Suits in Representative Capacity--Civil Actions in Name of State--Real Party in Interest to Bring Civil Action.
Part I · Rule 52: Parties · Last amended January 1, 1994 · Last verified July 22, 2026
In one sentenceRule 52.01 requires every civil action to be prosecuted in the name of the person or entity holding the claim, while letting executors, administrators, guardians, trustees, and certain statute-authorized parties sue in their own name on someone else's behalf.
Full Text of Rule 52.01
Amendment History
Adopted April 21, 1972, eff. Dec. 1, 1972. Amended Sept. 28, 1993, eff. Jan. 1, 1994.
Official Comment
This is substantially the same as prior Rule 52.01. Compare: Rule 17(a) of the Federal Rules of Civil Procedure.
Plain-English Summary
Rule 52.01 settles a question that has to be answered before any lawsuit can move forward: who gets to be the plaintiff? The rule's default answer is the real party in interest — the person or entity that owns the claim and stands to collect if the case succeeds. Naming the true owner keeps a defendant from being sued twice over the same wrong, once by the owner and again by someone standing in for them, and it lets the defendant raise defenses good against that owner specifically, such as a release, a settlement, or a prior payment.
The rule then lists representatives who may sue in their own name without joining the person they represent: an executor or administrator handling an estate, a guardian acting for a ward, a trustee of an express trust, a party who signed a contract for someone else's benefit, and any party a statute authorizes to sue in a representative capacity. Each of these stands in a recognized legal relationship to the underlying claim, so the rule lets them bring the case without adding the beneficiary as a named party in the caption.
The last sentence covers a narrower situation: when a Missouri statute directs that a case brought for someone else's use or benefit be filed in the name of the State of Missouri. Rule 52.01 does not create that requirement on its own — it tells the pleader to follow the statute's naming instructions whenever one applies, so the caption matches what the underlying law demands.
Frequently Asked Questions
What does “real party in interest” mean under Rule 52.01?
It refers to the person or entity holding the right being sued on — the one who would collect a judgment or is bound by one. Rule 52.01 requires that this person or entity be named as the plaintiff, unless one of the rule's listed exceptions applies.
Can a guardian or trustee sue without naming the person they represent?
Yes. Rule 52.01 lets an executor, administrator, guardian, trustee of an express trust, a party who contracted for another's benefit, or a party a statute authorizes act in a representative capacity to sue in their own name, without joining the person for whose benefit the case is brought.
Why does it matter to a defendant who is named as plaintiff?
Naming the real party in interest protects a defendant from facing a second lawsuit over the same claim brought by the true owner later, and it preserves the defendant's ability to raise defenses — such as a release or payment already made — that are good against that particular owner.
When would a Missouri lawsuit be brought in the name of the State of Missouri?
Rule 52.01 requires this only when a separate Missouri statute directs that a civil action for someone's use or benefit be filed in the state's name. The rule itself does not create such a requirement; it defers to whatever the applicable statute says.
Does an assignee who has been given a claim qualify to sue under Rule 52.01?
The rule's text addresses executors, administrators, guardians, trustees of an express trust, contracting parties, and statute-authorized parties. It does not itself list assignees as a separate category, so whether an assignee may sue depends on whether the assignment made that person the actual holder of the claim.
Is Rule 52.01 only about who sues, or does it also affect who can be sued?
The rule's text is directed at who prosecutes a civil action — that is, who may properly appear as plaintiff. It does not set separate standards for naming defendants.
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: real party in interestwho may suerepresentative capacitysuit in name of the stateexecutor administrator guardian trustee suits