Ohio Rev. Code § 109.16: Suits may be brought in Franklin county.

The attorney general may prosecute an action, information, or other proceeding in behalf of the state, or in which the state is interested, except prosecutions by indictment, in the proper court of Franklin county, or of any other county in which one or more of the defendants reside or may be found. No civil action, unless elsewhere specially provided, shall be commenced in Franklin county, if one or more of the defendants do not reside or cannot be found therein, unless the attorney general certifies on the writ that he believes the amount in controversy exceeds five hundred dollars.