Okla. Stat. tit. 42, § 206

The notice of lien shall state the name of the claimant, the name of the owner, a description of the property upon which the lien is being claimed, the amount for which the lien is claimed, and the license number of the real estate broker. The notice of lien shall recite that the information contained in the notice is true and accurate to the knowledge of the signators. The notice of lien shall be signed by the broker or by a person authorized to sign on behalf of the broker and shall be notarized.