C
- Caliber
- Camco Manufacturing
- Campbell Fittings
- Canada Metal (Martyr Anodes)
- Canadian Hydrographic Service
- Cannon
- Carefree of Colorado
- CargoLoc
- Carlisle Sanitary Maintenance
- Carroll Clean
- Carver by Covercraft
- Caviness Woodworking Company
- CDI/Rapair
- Centek Industries
- Century Plastics
- Cequent Performance Products
- Champion
- Chevron
- Chicago Hardware & Fixture Company
- Chrysler Marine
- Chukar Cherry Company
- Cipa
- Climate Technical Gear
- Cloyes Gear and Products
- CMC Marine
- Cobra Electronics
- Cobra Wire & Cable
- Coghlan's
- Cole Hersee
- Coleman
- Collinite
- Columbia Sportswear Company
- Computrol (Cannon)
- Conbraco Industries
- Continental Western
- Convert-A-Ball
- Corona Brushes
- Corroseal
- Corrosion Technologies
- Covertuff by Shoretex
- Covich-Williams
- CQR
- Crab Grabber Products
- CRC Industries
- Crescent
- Crosby
- Cross Manufacturing
- Crusader / Pleasurecraft (PCM)
- Custom Metal Spinning
- Cancord
- Cuda
- C.T. Johnson Enterprises
- Cofair Products, Inc.
- CMP Cordage