Utah R. Bus. & Chancery Ct. P. 14

(a) When defendant may bring in third party. At any time after commencement of the action a defendant, as a third-party plaintiff, may cause a summons and complaint to be served upon a person not a party to the action who is or may be liable to the defendant for all or part of the plaintiff’s claim, so long as the third-party plaintiff’s claimis a claim over which the court has jurisdiction. The third-party plaintiff need not obtain leave to make the service if the party files the third-party complaint no later than 14 days after serving the party’s original answer. Otherwise, the third-party plaintiff must obtain leave on motion upon notice to all parties to the action.

(b) The third-party defendant’s response. The person served with the summons and third-party complaint, hereinafter called the third-party defendant, must make defenses to the third-party plaintiff’s claim as provided in Rule 12 of the Utah Rules of Civil Procedure and any counterclaims against the third-party plaintiff and cross-claims against other third-party defendants as provided in Rule 13. The third-party defendant may assert against the plaintiff any defenses which the third-party plaintiff has to the plaintiff’s claim. The third-party defendant may also assert any claim against the plaintiff arising out of the transaction or occurrence that is the subject matter of the plaintiff’s claim against the third-party plaintiff. The third-party defendant may also proceed under this rule against any person not a party to the action who is or may be liable to the third-party defendant for all or part of the claim made in the action against the third-party defendant, so long as the claim is a claim over which the court has jurisdiction.

(c) Plaintiff’s claims against the third-party defendant and the third-party defendant’s response. The plaintiff may assert any claim against the third-party defendant arising out of the transaction or occurrence that is the subject matter of the plaintiff’s claim against the third-party plaintiff, so long as the claim is not a claim over which the court lacks jurisdiction, and the third-party defendant thereupon must assert defenses as provided in Rule 12 of the Utah Rules of Civil Procedure and any counterclaims and cross-claims as provided in Rule 13.

(d) When plaintiff may bring in third party. When a counterclaim is asserted against a plaintiff, the plaintiff may cause a third party to be brought in under circumstances which under this rule would entitle a defendant to do so.