- CIBC Bank USA
- Ciena Group
- Ciena Healthcare
- Cigna
- Circadia Health
- CIT Group
- Citadel Healthcare
- Citi
- Citizen’s News
- Citizens Memorial Hospital
- City of Hope
- CityBizList
- Cityblock Health
- CivicScience
- Civitas Solutions
- CLA
- Clark Retirement Communities
- Clayton Dublier & Rice
- Clear Choice Health Care
- ClearCare