Ohio Revised Code Title XLV. Motor Vehicles Aeronautics Watercraft § 4509.55

(A) Any policy which grants the coverage required for a motor-vehicle liability policy may also grant any lawful coverage in excess of or in addition to the coverage specified for a motor-vehicle liability policy and such excess or additional coverage shall not be subject to sections 4509.01 to 4509.78, inclusive, of the Revised Code. With respect to a policy which grants such excess or additional coverage the term “motor-vehicle liability policy” shall apply only to that part of the coverage which is required by such sections.

(B) Any motor-vehicle liability policy may provide that the insured shall reimburse the insurance carrier for any payment the insurance carrier would not have been obligated to make under the terms of the policy except for such sections.

(C) Any motor-vehicle liability policy may provide for the prorating of the insurance thereunder with other valid and collectible insurance.