Okla. Stat. tit. 19 § 290
He shall keep an index to chattel mortgages, bills of sale and other instruments affecting title to or incumbering personal property, required by law to be recorded, in which shall be entered in separate columns, the number of the instrument, name of grantor alphabetically, and the name of grantee, the year, month, day, hour and minute of filing, the amount secured, a description of the property, and dates when and by whom canceled; said chattel mortgage when so indexed to be numbered, filed and kept in his office, and when said mortgage or bill of sale is released or canceled the register shall note the same on the back of the instrument and on the index, in the proper column, giving the date and by whom said instrument is canceled.
Okla. Stat. tit. 19, § 290