Okla. Admin. Code § 710:10-7-6
The five-year period of allowable ad valorem manufacturing exemption for any qualifying manufacturing facility property shall begin on January 1 following the initial qualifying use of the property in the manufacturing process as provided by law. Failure to claim an exemption for which a qualifying manufacturing concern may be eligible shall not toll or extend the five-year period of allowable exemption. Any remaining eligibility for previously acquired assets may be claimed for the following year based on the initial year of acquisition. Oklahoma Constitution Article 10 Section 22A prohibits the filing of an exemption application for any prior year(s) beginning January 1, 2009. The application must be made in the same year as the exemption is requested.
Okla. Admin. Code § 710:10-7-6