Ohio Rev. Code § 3125.43
The department of taxation shall not provide any information to the office of child support, except as provided in this section. For purposes of the establishment of paternity, the establishment, modification, or enforcement of support orders, and the location of absent parents pursuant to child support enforcement activities and activities to establish and enforce orders allocating parenting rights and responsibilities and parenting time orders, the office is authorized to obtain information concerning the residential address and income of taxpayers if that information is contained in the state tax records maintained by the department. The department shall not provide any information to the office if the provision of the information is prohibited by state or federal law.
R.C. § 3125.43