Ind. Code § 32-29-3-1

Sec. 1. The release of a mortgage, lease, or other instrument required by law to be recorded written upon the margin, or upon the record, of any mortgage in Indiana by the party authorized to release the mortgage is not a valid release of the mortgage, lease, or other instrument unless the release is attested on the record by the recorder or deputy recorder of the county in which the mortgage is recorded.