Ohio Rev. Code Ann. § 3919.28

An action may be brought against a corporation, company, or association organized under section 3919.01 of the Revised Code, or against any foreign corporation, company, or association described in section 3919.21 of the Revised Code doing business in this state, in any county where such cause of action arises, and summons may be issued and service had as provided by law for the issuance and service of such writs in the court of common pleas.