Okla. Stat. tit. 60 § 754
The disclaimer defined in Section 751 of this title shall be effective upon being filed on the miscellaneous docket in the office of the county clerk of any county of the State of Oklahoma in which the district court would have jurisdiction and venue of the matter. A copy of the disclaimer shall be delivered or mailed to the trustee of any trust in which the interest disclaimed exists or to any other person who has legal title to, or possession of, the property in which the interest disclaimed exists, and no such trustee or person shall be liable for any otherwise proper distribution or other disposition made without actual notice of the disclaimer. If an interest in or relating to real estate is disclaimed, the original of the disclaimer, or a copy of the disclaimer certified as true and complete by the custodian wherein the disclaimer has been filed, shall also be filed with the county clerk in the county or counties where the real estate is situated and shall constitute notice to all persons only from and after the time of the filing.
Okla. Stat. tit. 60, § 754