Under the Federal Rules of Civil Procedure (FRCP), counterclaims are either compulsory or permissive.
[citation needed] A claim is a compulsory counterclaim if, at the time of serving the pleading, This last (fourth) requirement is explained in the official notes as follows: When a defendant, if he desires to defend his interest in property, is obliged to come in and litigate in a court to whose jurisdiction he could not ordinarily be subjected, fairness suggests that he should not be required to assert counterclaims, but should rather be permitted to do so at his election.
It will apply to various cases described in Rule 4(e), as amended, where service is effected through attachment or other process by which the court does not acquire jurisdiction to render a personal judgment against the defendant.
Clause (2) will also apply to State courts jurisdictionally grounded on attachment or the like, and removed to the Federal courts.If the counterclaim is compulsory, it must be brought in the current action or it is waived and lost forever.
Various tests have been proposed for when a counterclaim arises from the same transaction or occurrence, including same issues of fact and law, use of the same evidence, and logical relation between the claims.