Okla. Stat. tit. 15, § 15-141.28: Hearings

A. Whenever the Insurance Commissioner has reason to believe

that any person has engaged, or is engaging, in this state in any

unfair method of competition or any unfair or deceptive act or

practice as defined in Section 26 of this act, or is engaging in the

business of service warranty without being properly licensed, and

that a proceeding by the Commissioner in respect thereto would be in

the interest of the public, the Commissioner shall conduct or cause

to have conducted a hearing in accordance with Article II of the

Administrative Procedures Act.

B. A statement of charges, notice, order, or other process may

be served by anyone duly authorized by the Insurance Commissioner,

either in the manner provided by law for service of process in civil

actions or by certifying and mailing a copy thereof to the person

affected by such statement, notice, order, or other process at the

residence or principal office or place of business of the person.

The verified return by the person so serving such statement, notice,

order, or other process, setting forth the manner of the service, is

proof of the same; and the return postcard receipt for such

statement, notice, order, or other process, certified and mailed as

provided in this subsection, is proof of service of the same.