What does Rule 13 govern regarding counterclaims?

Rule 13 of the Federal Rules of Civil Procedure indeed governs counterclaims and provides specific guidelines regarding when they must be asserted. It delineates between compulsory counterclaims and permissive counterclaims. A compulsory counterclaim is one that arises out of the same transaction or occurrence that is the subject matter of the opposing party's claim, and it must be raised in the current litigation or it is waived. Conversely, permissive counterclaims are those that do not arise out of the same transaction or occurrence and may be asserted at the party's discretion.

This distinction is crucial because it ensures judicial efficiency by encouraging parties to resolve all related disputes in one action. Consequently, failing to assert a compulsory counterclaim could lead to the loss of the opportunity to pursue that claim in the future, as it effectively becomes barred from subsequent litigation. Thus, the correct explanation of Rule 13’s application highlights the necessity for parties to be vigilant about asserting their counterclaims based on their nature and relation to the original claim. This is why the assertion concerning guidelines for when counterclaims must be asserted is accurate.