M.R. Civ. P. 13

(a) Compulsory Counterclaims.

(1) Pleadings. Unless otherwise specifically provided by statute or

unless the relief demanded in the opposing party’s claim is for damage arising

out of the ownership, maintenance or control of a motor vehicle by the pleader,

a pleading shall state as a counterclaim any claim which at the time of serving

the pleading the pleader has against any opposing party, if it arises out of the

transaction or occurrence that is the subject matter of the opposing party’s

claim, and does not require for its adjudication the presence of third parties of

whom the court cannot acquire jurisdiction. But the pleader need not state the

claim if (A) at the time the action was commenced the claim was the subject of

another pending action, or (B) the opposing party brought suit upon the claim

by attachment or other process by which the court did not acquire jurisdiction

to render a personal judgment on that claim, and the pleader is not stating any

counterclaim under this Rule 13.

(2) Removal of Claims Not Within the Subject-Matter Jurisdiction of

the District Court. If a compulsory counterclaim filed in the District Court is not

within the subject-matter jurisdiction of that court, the pleader shall

simultaneously file and serve notice of removal and pay the required removal

fee under Rule 54A, and the action shall be removed to the Superior Court as

provided in that rule.

(b) Permissive Counterclaims. A pleading may state as a counterclaim

any claim against an opposing party that is within the subject-matter

jurisdiction of the court.

(c) Counterclaim Exceeding Opposing Claim. A counterclaim may or may

not diminish or defeat the recovery sought by the opposing party. It may claim

relief exceeding in amount or different in kind from that sought in the pleading

of the opposing party.

(d) Counterclaim Against the State. These rules shall not be construed to

enlarge beyond the limits now fixed by law the right to assert counterclaims or

to claim credits against the State of Maine or an officer or agency thereof.

(e) Counterclaim Maturing or Acquired After Pleading. A claim which

either matured or was acquired by the pleader after serving a pleading may,

with the permission of the court, be presented as a counterclaim by

supplemental pleading.

(f) Omitted Counterclaim. When a pleader fails to set up a counterclaim

through oversight, inadvertence, or excusable neglect, or when justice requires,

the pleader may by leave of court set up the counterclaim by amendment.

(g) Cross-Claim Against Co-party. A pleading may state as a cross-claim

any claim by one party against a co-party that is within the subject-matter

jurisdiction of the court and arises out of the transaction or occurrence that is

the subject matter either of the original action or of a counterclaim therein or

relating to any property that is the subject matter of the original action. Such

cross-claim may include a claim that the party against whom it is asserted is or

may be liable to the cross-claimant for all or part of a claim asserted in the

action against the cross-claimant.

(h) Joinder of Additional Parties. Persons other than those made parties

to the original action may be made parties to a counterclaim or cross-claim in

accordance with the provisions of Rules 19 and 20.

(i) Separate Trials; Separate Judgment. If the court orders separate trials

as provided in Rule 42(b), judgment on a counterclaim or cross-claim may be

rendered in accordance with the terms of Rule 54(b) even if the claims of the

opposing party have been dismissed or otherwise disposed of.