Okla. Stat. tit. 68, § 68-2941: Release and extinguishment of liens

Any and all ad valorem taxes and assessments, together with

interest, penalty and costs, heretofore or hereafter levied for any

year upon any real property and any lien created thereby in this

state are hereby released and extinguished forever upon the

expiration of seven (7) years after the date upon which any part

thereof became or shall become due, and any lien for ad valorem

taxes or assessments together with interest, penalty and costs, for

any tax year or years which has heretofore accrued or may hereafter

accrue because of the failure of any real property to have been

assessed or taxed and placed upon any tax roll, shall be and are

hereby extinguished upon the expiration of seven (7) years from the

date when such lien would have accrued had such assessment or

assessments been made or placed upon the tax rolls as required by

law.