Utah Code § 58-55-604: Proof of licensure to maintain or commence action.

A contractor or alarm business or company may not act as agent or commence or maintain any action in any court of the state for collection of compensation for performing any act for which a license is required by this chapter without alleging and proving that the licensed contractor or alarm business or company was appropriately licensed when the contract sued upon was entered into, and when the alleged cause of action arose.