Okla. Stat. tit. 17, § 17-158.29: Annexation of area to city or town

When an area, which is included in whole or in part in any

territory or territories certified to a retail electric supplier or

suppliers under this act, is annexed to and becomes a part of an

incorporated city or town, the certification of the territory or

territories under this act shall be subject to the provisions of the

Retail Electric Consumer Cost Reduction, Safety and Service

Efficiency Act.