This would appear to be a breach of contract suit:
2305.06 Contract in writing.
Except as provided in sections 126.301 and 1302.98 of the Revised Code, an action upon a specialty or an agreement, contract, or promise in writing shall be brought within fifteen years after the cause thereof accrued.
Effective Date: 07-01-1993
2305.07 Contract not in writing - statutory liability.
Except as provided in sections 126.301 and 1302.98 of the Revised Code, an action upon a contract not in writing, express or implied, or upon a liability created by statute other than a forfeiture or penalty, shall be brought within six years after the cause thereof accrued.
Effective Date: 07-01-1993
You can find other limitations of actions here, but I don't know what else it would fall under?
http://codes.ohio.gov/orc/2305

