R. 4:7-1. — Mandatory or Permissive Counterclaims

Except as otherwise provided by R. 4:64-5 (foreclosure actions) and R. 4:67-4 (summary actions), a pleading may state as a counterclaim any claim against the opposing party whether or not arising out of the transaction or occurrence that is the subject matter of the opposing party's claim. A defendant, however, either failing to comply with R. 4:30A (entire controversy doctrine) or failing to set off a liquidated debt or demand or a debt or demand capable of being ascertained by calculation, shall thereafter be precluded from bringing any action for such claim or for such debt or demand which might have been so set off.