Tennessee Code Title 56. Insurance § 56-7-1104

(a) Upon a sheriff's return of “not to be found” within the particular county, or upon the secretary of state being unable to complete process upon the defendant or defendants, the plaintiff may serve demand notice upon the liability insurance carrier to reveal the location and whereabouts of the defendant automobile owner or operator.

(b) If the carrier is not a domestic company, the demand notice shall be through the commissioner. The demand notice shall be by certified mail with a return receipt requested and shall include a certified copy of the sheriff's return.

(c) The liability insurance carrier shall, upon notice, reveal to the plaintiff or the plaintiff's attorney any information it possesses as to the location of the defendant automobile operator or owner.