- Carlsbad CVB
- Casa Colina Hospital
- Catholic Charities of California
- Catholic Diocese of Sacramento
- Catholic Healthcare West
- CBIA
- CC Myers Inc.
- Cedars-Sinai Liver Center
- Cedars-Sinai Medical Center
- Center of Hope
- Centinela Hospital Medical Center
- Central California Blood Centers
- Central County Hispanic Chamber of Commerce
- Central County United Way
- Century Wilshire Hotel, Los Angeles
- Cervitor Kitchens, Inc.
- CHA Hollywood Presbyterian Medical Center
- Chevron Texaco
- Children's Hospital Los Angeles
- Children's Hospital of Orange County
- Children's Hospital San Diego
- Chinese American Citizens Alliance - Peninsula
- Chinese American Club of Southern California
- Chinese Newcomers Service Center
- Chino Valley Medical Center
- CHOC Children's
- CHOC Children's at Mission Hospital
- CHOC- Children's Hospital of Orange County
- Chong-Parteners
- Cisco
- Cisco Brothers Corporation
- City of Cruz
- City of Dana Point
- City of Hope National Medical Center
- Clinica Sierra Vista
- Clinimetrics
- Clovis Community Medical Center
- CMA
- CMC Americas Inc.
- Coast Independent Review Board
- Coast Plaza Hospital
- Coherent Inc.
- Colorado River Medical Center
- Colusa Regional Medical Center
- Community Hospital of Huntington Park
- Community Hospital of San Bernardino
- Community Regional Medical Center
- Community Regional Medical Center - Fresno
- Concierge Media Group, Inc.
- Conor Medsystems