Organizers
- CRS Gymnastics
- Cru - Urban Sumit Adventures
- Crucible Racing LLC
- CRUK Louth
- CRUSA
- Crush Basketball Club
- Crush Rush
- Crushers Softball
- Cryo Depot
- Crystal Cove State Park
- Crystal Cove State Park Junior Lifeguards
- Crystal Crime Prevention Board
- Crystal Ice House
- Crystal Lake Sailing School
- Crystal Mountain INC
- Crystal Mountain Resort
- Crystal Springs Golf Course
- CS Blue Devils
- CS East Coast Championships and/or Kokushikai Judo Camp
- CSA
- CSC Soccer School of Excellence Camp
- Csc-Fon
- CSCRB, Inc.
- CSHP (California Society of Health-System Pharmacists)
- CSM Active
- CSP Dance Studios
- CS-Square Summer Camps
- CSU Professional Veterinary Medicine Program
- CSU, Chico Rec Sports Summer Camp
- CSUB
- CSUB Men's Basketball
- CSUDH BASKETBALL
- CSUDH SOCCER
- CSUF Army ROTC
- CSUN Women's Basketball Foundation
- CSz Theater Chicago
- CSz Theatre Chicago
- CT Audubon Society, Inc.
- CT Cycling Advancement Program
- CT Science Center
- CT Veterans Day Patriot Race
- CTC Tennis
- CU Little League
- C-U Marathon, LLC
- CU Science Discovery
- Cub Creek Inc.
- Cub Creek Science Camp / Animal Camp Jamaica
- Cub Creek Science Camp and Animal Camp Jamaica
- Cuba Little League
- Cubamerica Foundation
