Okla. Stat. tit. 19, § 1259

The owner or holder of any road improvement bonds heretofore or hereafter issued by any county in the State of Oklahoma for the payment of road or street improvements in any such county shall register such bond with the county clerk or appointed agent of such county by presenting same to such clerk, who shall thereupon enter in a book to be kept for that purpose, a description of such bond, and the name of the owner or holder presenting the same for registration, and the date of registration thereof, and endorse upon such bond, over his signature, or a facsimile of his signature, the legend, "registered in my office". After registration of any such bond no transfer or assignment thereof shall be valid until such transfer or assignment has been registered with the clerk or appointed agent of such county.