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 that is the subject matter of the opposing party's claim and does not require for its adjudication the presence of third parties over whom the court cannot acquire jurisdiction, except that such a claim need not be so stated if, at the time the action was commenced, the claim was the subject of another pending action.
A pleading may state as a counterclaim any claim against an opposing party not arising out of the transaction that is the subject matter of the opposing party's 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.
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 Minnesota or an officer or agency thereof.
A claim which either matured or was acquired by the pleader after serving a pleading may, by leave of court, be presented as a counterclaim by supplemental pleading.
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.
A pleading may state as a cross-claim any claim by one party against a co-party arising 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.