Okla. Stat. tit. 19, § 19-290: Chattel mortgage record

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.