(A) Designation of Parties. The party who commences a civil action is designated as plaintiff and the adverse party as defendant. In an appeal the relative position of the parties and their designations as plaintiff and defendant are the same, but they are also designated as appellant and appellee.
Rule 2.201.Parties Plaintiff and Defendant; Capacity
Current through May 1, 2026 · Last verified July 6, 2026
In one sentenceRule 2.201 requires a lawsuit to be brought in the name of the real party in interest, lists who may sue or be sued in their own name, sets a procedure for suing people whose identity can't be determined, and explains how minors and incompetent persons are represented in litigation.
Full Text of Rule 2.201
(B) Real Party in Interest. An action must be prosecuted in the name of the real party in interest, subject to the following provisions:
(1) A personal representative, guardian, conservator, trustee of an express trust, a party with whom or in whose name a contract has been made for the benefit of another, or a person authorized by statute may sue in his or her own name without joining the party for whose benefit the action is brought.
(2) An action on the bond of a public officer required to give bond to the people of the state may be brought in the name of the person to whom the right on the bond accrues.
(3) An action on a bond, contract, or undertaking made with an officer of the state or of a governmental unit, including but not limited to a public, municipal, quasi-municipal, or governmental corporation, an unincorporated board, a public body, or a political subdivision, may be brought in the name of the state or the governmental unit for whose benefit the contract was made.
(4) An action to prevent illegal expenditure of state funds or to test the constitutionality of a statute relating to such an expenditure may be brought:
(a) in the name of a domestic nonprofit corporation organized for civic, protective, or improvement purposes; or
(b) in the names of at least 5 residents of Michigan who own property assessed for direct taxation by the county where they reside.
(C) Capacity to Sue or be Sued.
(1) A natural person may sue or be sued in his or her own name.
(2) A person conducting a business under a name subject to certification under the assumed name statute may be sued in that name in an action arising out of the conduct of that business.
(3) A partnership, partnership association, or unincorporated voluntary association having a distinguishing name may sue or be sued in its partnership or association name, in the names of any of its members designated as such, or both.
(4) A domestic or a foreign corporation may sue or be sued in its corporate name, unless a statute provides otherwise.
(5) Actions to which the state or a governmental unit (including but not limited to a public, municipal, quasi-municipal, or governmental corporation, an unincorporated board, a public body, or a political subdivision) is a party may be brought by or against the state or governmental unit in its own name, or in the name of an officer authorized to sue or be sued on its behalf. An officer of the state or governmental unit must be sued in the officer's official capacity to enforce the performance of an official duty. An officer who sues or is sued in his or her official capacity may be described as a party by official title and not by name, but the court may require the name to be added.
(D) Unknown Parties; Procedure.
(1) Persons who are or may be interested in the subject matter of an action, but whose names cannot be ascertained on diligent inquiry, may be made parties by being described as:
(a) unknown claimants;
(b) unknown owners; or
(c) unknown heirs, devisees, or assignees of a deceased person who may have been interested in the subject matter of the action. If it cannot be ascertained on diligent inquiry whether a person who is or may be interested in the subject matter of the action is alive or dead, what disposition the person may have made of his or her interest, or where the person resides if alive, the person and everyone claiming under him or her may be made parties by naming the person and adding “or [his or her] unknown heirs, devisees, or assignees.”
(2) The names and descriptions of the persons sought to be made parties, with a statement of the efforts made to identify and locate them, must be stated in the complaint and verified by oath or affirmation by the plaintiff or someone having knowledge of the facts in the plaintiff's behalf. The court may require a more specific description to be made by amendment.
(3) A publication giving notice to persons who cannot be personally served must include the description of unknown persons as set forth in the complaint or amended complaint.
(4) The publication and all later proceedings in the action are conducted as if the unknown parties were designated by their proper names. The judgment rendered determines the nature, validity, and extent of the rights of all parties.
(5) A person desiring to appear and show his or her interest in the subject matter of the action must proceed under MCR 2.209. Subject to that rule, the person may be made a party in his or her proper name.
(E) Minors and Incompetent Persons. This subrule does not apply to proceedings under chapter 5.
(1) Representation.
(a) If a minor or incompetent person has a conservator, actions may be brought and must be defended by the conservator on behalf of the minor or incompetent person.
(b) If a minor or incompetent person does not have a conservator to represent the person as plaintiff, the court shall appoint a competent and responsible person to appear as next friend on his or her behalf, and the next friend is responsible for the costs of the action.
(c) If the minor or incompetent person does not have a conservator to represent the person as defendant, the action may not proceed until the court appoints a guardian ad litem, who is not responsible for the costs of the action unless, by reason of personal misconduct, he or she is specifically charged costs by the court. It is unnecessary to appoint a representative for a minor accused of a civil infraction.
(2) Appointment of Representative.
(a) Appointment of a next friend or guardian ad litem shall be made by the court as follows:
(i) if the party is a minor 14 years of age or older, on the minor's nomination, accompanied by a written consent of the person to be appointed;
(ii) if the party is a minor under 14 years of age or an incompetent person, on the nomination of the party's next of kin or of another relative or friend the court deems suitable, accompanied by a written consent of the person to be appointed; or
(iii) if a nomination is not made or approved within 21 days after service of process, on motion of the court or of a party.
(b) The court may refuse to appoint a representative it deems unsuitable.
(c) The order appointing a person next friend or guardian ad litem must be promptly filed with the clerk of the court.
(3) Security.
(a) Except for costs and expenses awarded to the next friend or guardian ad litem or the represented party, a person appointed under this subrule may not receive money or property belonging to the minor or incompetent party or awarded to that party in the action, unless he or she gives security as the court directs.
(b) The court may require that the conservator representing a minor or incompetent party give security as the court directs before receiving the party's money or property.
(4) Incompetency While Action Pending. A party who becomes incompetent while an action is pending may be represented by his or her conservator, or the court may appoint a next friend or guardian ad litem as if the action had been commenced after the appointment.
Amendment History
Michigan tracks the orders that adopt and amend its Court Rules in a separate administrative record rather than printing a history note beneath each rule in the compiled rules text reproduced here. The text above is verified current through the source’s own May 1, 2026 update; for the full order-by-order history of this rule, see the Michigan Supreme Court’s rules and orders page.
Plain-English Summary
Whoever files a complaint is the plaintiff, and whoever must answer it is the defendant; on appeal, the same people keep those labels but pick up the additional titles of appellant and appellee. Every action must be brought in the name of the real party in interest, though the rule carves out several exceptions: a personal representative, guardian, conservator, trustee, a party who contracted for someone else's benefit, or anyone else a statute authorizes can sue in their own name without joining the person who benefits from the outcome. Special provisions cover suits on a public officer's bond and taxpayer challenges to illegal government spending, which can be brought by a qualifying nonprofit or by at least five Michigan residents who own taxed property in the relevant county. Separately, natural persons, businesses operating under an assumed name, partnerships and associations, corporations, and government units can each sue or be sued in their own name or title.
When a person who might have an interest in the case can't be identified despite diligent inquiry, the complaint can describe them as an unknown claimant, owner, or heir, stating the efforts made to find them; once the court allows notice by publication, the case proceeds against them as if they had been named, and the resulting judgment binds them just the same. Anyone in that position who later wants to appear and assert their own interest can do so through intervention.
Minors and incompetent persons generally act through a conservator if one exists. Without a conservator, a plaintiff needs a next friend, who is responsible for the costs of the action, while a defendant needs a guardian ad litem, who generally isn't. The court appoints these representatives on nomination — the minor's own nomination if 14 or older, otherwise a relative's or friend's, or the court's own motion if no nomination is made within 21 days — and can require security before that representative handles the party's money or property. If a party becomes incompetent while the case is already underway, the same representation rules apply going forward.
Frequently Asked Questions
What is the "real party in interest" rule?
An action must generally be brought in the name of the person or entity that holds the legal right being enforced, though the rule lets several kinds of representatives — trustees, guardians, conservators, and others — sue in their own name on someone else's behalf.
Can I sue someone whose name I don't know?
Yes, by describing them as an unknown claimant, owner, or heir, stating your efforts to identify them in the complaint, and giving notice by publication once the court authorizes it.
Who represents a minor or a person who can't manage their own affairs in a lawsuit?
A conservator represents them if one exists. Otherwise, the court appoints a next friend for a minor or incompetent plaintiff, or a guardian ad litem for a minor or incompetent defendant.
Do I have to prove my capacity to sue in every case?
No. Capacity is generally presumed and becomes an issue only if the opposing side specifically challenges it with supporting facts, as provided in Rule 2.112.
Source & verification. The rule text is reproduced verbatim from the
official Michigan Court Rules (MCR 2.201). Prescribed by the Supreme Court of Michigan (Mich. Const. 1963, art. VI, § 5). The plain-English summary is original and written by us. Last verified July 6, 2026. ·
Official source
Also known as: real party in interest Michigannext friend Michigan lawsuitguardian ad litem Michigancapacity to sue Michiganunknown parties lawsuit Michigansuing a minor defendant Michigan