Okla. Stat. tit. 36, § 36-1219.5: Modification of existing or issuance of new coverage -

Consent.

No insurer shall modify a group or individual policy of existing

coverage or issue new coverage under an accident and health

insurance policy unless written consent for such modification or

issuance is obtained from the policyholder. However, this section

shall not be construed as prohibiting a modification that is

provided for in an existing policy that has been filed and approved

by the Insurance Commissioner.