Okla. Stat. tit. 19 § 299
The county assessor, county clerk and county treasurer of any county may adopt a system of land parcel identifier numbers whereby the same land identifier numbers shall be used by the county assessor, county clerk and county treasurer to designate a tract of real property situated within the county.
In any county where this system has been adopted, the county clerk shall not accept for filing or recording any map, plat, deed, mortgage, lease or other instrument affecting real property unless the land parcel identifier numbers for all of the land parcels described and affected are affixed on the face of the map, plat, deed, mortgage, lease or other instrument. Provided that, failure to comply with these provisions shall not affect the validity of any such instrument that is duly recorded.
Okla. Stat. tit. 19, § 299