Ohio Revised Code Title LV. Roads Highways Bridges § 5516.06

(A) Advertising devices located in zoned or unzoned industrial or commercial areas adjacent to highways on the primary system that conform to rules adopted by the director of transportation;

(B) Signs lawfully in existence on October 22, 1965, that the director, subject to the approval of the secretary of the United States department of transportation, has determined to be landmark signs, including signs on farm structures or natural surfaces, which are of historic or artistic significance;

(C) Advertising devices that are located on the premises of a professional sports facility and that conform to rules adopted by the director.