EXHIBIT (15) LETTER RE: UNAUDITED FINANCIAL INFORMATION Board of Directors and Shareholders Park-Ohio Holdings Corp. We are aware of the incorporation by reference in the following Registration Statements of Park-Ohio Holdings Corp., for the registration of its common stock of our report dated August 12, 2003 relating to the unaudited consolidated interim financial statements of Park-Ohio Holdings Corp., which are included in its Form 10-Q for the quarter ended June 30, 2003. <Table> <Caption> SHARES REGISTRATION STATEMENT DESCRIPTION REGISTERED - ---------------------- ---------------------------------- ---------- Form S-8 (33-01047) Individual Account Retirement Plan 1,500,000 Form S-8 (333-58161) 1998 Long-Term Incentive Plan 550,000 </Table> /s/ Ernst & Young LLP Cleveland, Ohio August 12, 2003 25