- Accident Fund Insurance Company
- Aegis
- American Modern Insurance Group
- AmWINS
- BCBS
- CNA
- CNA Surety
- CompSource Oklahoma
- Farmers Alliance Mutual Insurance
- Foremost
- Hartford
- Liberty Mutual
- Mercury
- Mid-Continent
- MSA Group
- National American
- North Star Mutual Insurance Company
- Old Republic Surety
- Progressive
- Safeco
- Travelers
- Union Standard Group
- Zurich