Ohio Revised Code Title I. State Government § 153.44

Before work is done or material furnished, all contracts that exceed twenty thousand dollars in amount shall be submitted by the board of county commissioners to the prosecuting attorney of the county.  If found to be in accordance with sections 153.01 to 153.60, inclusive, of the Revised Code, and a certificate to that effect is indorsed thereon by the prosecuting attorney, such contracts shall have full effect, otherwise the contract shall be void.