Okla. Stat. tit. 16, § 16-78: Definitions

(a) "Marketable record title" means a title of record as

indicated in Section 71 of this title, which operates to extinguish

such interests and claims, existing prior to the effective date of

the root of title, as are stated in Section 73 of this title.

(b) "Records" includes probate and other official public

records, as well as records in the county clerk's office.

(c) "Recording," when applied to the official public records of

any office or court, includes filing.

(d) "Person dealing with land" includes a purchaser of any

estate or interest therein, a mortgagee, a levying or attaching

creditor, a land contract vendee, or any other person seeking to

acquire an estate or interest therein, or impose a lien thereon.

(e) "Root of title" means that conveyance or other title

transaction in the chain of title of a person, purporting to create

the interest claimed by such person, upon which he relies as a basis

for the marketability of his title, and which was the most recent to

be recorded as of a date thirty (30) years prior to the time when

marketability is being determined. The effective date of the "root

of title" is the date on which it is recorded.

(f) "Title transaction" means any transaction affecting title to

any interest in land, including title by will or descent, title by

tax deed, mineral deed, lease or reservation, or by trustee's,

referee's, guardian's, executor's, administrator's, master in

chancery's, sheriff's or marshal's deed, or decree of any court, as

well as warranty deed, quitclaim deed, or mortgage.