Okla. Stat. tit. 36, § 36-6002: Approval by Insurance Commissioner

No form or plan of insurance covering any group or combination

of persons or risks shall be written or delivered within or outside

of this state to cover Oklahoma persons or risks at any preferred

rate or form other than that offered to persons not in such group,

and the public generally, unless such form, plan or policy and the

rates or premiums to be charged therefor have been submitted to and

filed or approved by the Insurance Commissioner.