Ohio Revised Code Title LIII. Real Property § 5301.21

When the owners of adjoining tracts of land, or of lots in a municipal corporation, agree upon the site of a corner or line common to such tracts or lots, in a written instrument containing a pertinent description thereof, either with or without a plat, executed, acknowledged, and recorded as are deeds, such corner or line thenceforth shall be established as between the parties to such agreement, and all persons subsequently deriving title from them.

Such agreement shall be recorded by the county recorder in the official records.  The original agreement, after being so recorded, or a certified copy thereof from the record, is competent evidence in any court in this state against a party thereto, or person in privity with a party.

When a tract of land is owned by the state, the officer or board having administrative control thereof, with the approval of the attorney general, may execute said written instrument and following recording in the county where the land is situated, said instrument shall be filed with the auditor of state with the evidence of title to the land affected.