5 1 NASDAQ 0001128308 Director Ohio Casualty Corporation 0000073952 31-0783294 12/31/02 5 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 5 ANNUAL STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP [ ] Check box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. [ ] Form 3 Holdings Reported [ ] Form 4 Transactions Reported 1. Name and Address of Reporting Person(s) MARCUM, STEPHEN S. 1345 SMITH ROAD HAMILTON, OH 45013 2. Issuer Name and Ticker or Trading Symbol Ohio Casualty Corporation (OCAS) 3. I.R.S. Identification Number of Reporting Person, if an entity (Voluntary) 4. Statement for Month/Year 12/02 5. If Amendment, Date of Original (Month/Year) 6. Relationship of Reporting Person(s) to Issuer (Check all applicable) [X] Director [ ] 10% Owner [ ] Officer (give title below) [ ] Other (specify below) Non-Employee Director 7. Individual or Joint/Group Filing (Check Applicable Line) [X] Form filed by One Reporting Person [ ] Form filed by More than One Reporting Person

SIGNATURE OF REPORTING PERSON /S/ MARCUM, STEPHEN S. DATE 02/06/03

OHIO CASUALTY CORP 5