Okla. Stat. tit. 16, § 16-16.1: Filing of special improvement district assessment in

office of county clerk.

Within thirty (30) days after the effective date of this act or

after the formation of a new special improvement, protection, or

conservancy district, the clerks and secretaries of all such

districts shall record in the office of the county clerk of the

county in which any part of the district is located a certified copy

of the ordinance, resolution, or order of the court creating the

district, and a plat of all parcels or tracts of land included in

said district. If thereafter the boundaries of the district are

enlarged or diminished by the creating authority, the clerk shall

record a certified copy of the ordinance, resolution, or order of

the court so enacted in the office of the county clerk within thirty

(30) days after said enactment. The county clerk shall record the

plat of the special district at such fees as provided by law for

recording plats, and indicate the land affected on the numerical

index. Liens for assessments levied thereafter by any such district

shall not attach to the lands within the district until such

ordinance, resolution, or order of the court is recorded. Provided

that nothing herein shall be construed as affecting any liens or

assessments existing prior to the effective date of this act.