Tennessee Code Title 48. Corporations and Associations § 48-15-104

(a) A corporation's registered agent is the corporation's agent for service of process, notice, or demand required or permitted by law to be served on the corporation.

(b) Whenever a domestic or foreign corporation authorized to do business in this state fails to appoint or maintain a registered agent in this state, whenever its registered agent cannot be found with reasonable diligence, whenever a foreign corporation shall transact business or conduct affairs in this state without first procuring a certificate of authority to do so from the secretary of state, or whenever the certificate of authority of a foreign corporation shall have been withdrawn or revoked, then the secretary of state shall be an agent of such corporation upon whom any such process, notice or demand may be served.

(c) Whenever a domestic or foreign corporation authorized to do business in this state is an employer within the meaning of the Workers' Compensation Law and such corporation is, for the purpose of such Workers' Compensation Law, self insured or a part of a self-insurance pool as provided in title 50, chapter 6, part 4, such corporation shall, for workers' compensation actions only, be required to appoint the commissioner of commerce and insurance and the commissioner's chief deputy, or their successors, as its true and lawful attorneys upon either of whom all lawful process in any such action or legal proceeding against it may be served as is required of insurance companies by § 56-2-103.

(d) This section does not prescribe the only means, or necessarily the required means, of serving a corporation.