Ohio Revised Code Title LIII. Real Property § 5309.74

Before any person can convey, transfer, charge, or deal with any registered land, or any interest therein, as an attorney in fact for another, the deed or instrument empowering such person to so act shall be filed with the county recorder, and a memorial thereof entered upon the registered certificate of title giving the exact time of the filing. Such power of attorney may be revoked by revocation in writing, but such revocation shall not take effect until it is filed with the recorder and noted as a memorial on the register of title. Death shall not effect a revocation of such power of attorney until notice of the death is filed with the recorder and entered on the certificate of title.