| Company Name | Software Titles |
|---|---|
| Compliance Systems | 4 |
| CASIO | 4 |
| Camtech | 4 |
| Computer | 4 |
| ConeXware | 4 |
| Cypherix | 4 |
| ContMedia | 4 |
| CareerTrack | 4 |
| ClickView | 4 |
| Cmotech | 4 |
| Chikka Asia | 4 |
| CapaSystems A-S | 5 |
| CT Summation | 5 |
| Canary Labs | 5 |
| COWON | 5 |
| CubexSoft Technologies | 5 |
| ComputerAssociates | 5 |
| Canopus | 5 |
| Calyx Software | 5 |
| Clipsal Integrated Systems | 6 |
| Comcast | 6 |
| Contex | 6 |
| Chapura | 6 |
| ChessBase | 6 |
| Cummins | 6 |
| Cigati Solutions | 7 |
| Colasoft | 7 |
| CollabNet | 7 |
| COMODO | 7 |
| Chicony | 7 |
| Client Version | 8 |
| Cadence Design Systems | 8 |
| Contributors | 9 |
| Crawler | 9 |
| Colin Watson | 9 |
| CirrusLogic | 10 |
| CoffeeCup | 10 |
| Compuware | 10 |
| Cengage | 10 |
| Computer Sciences | 12 |
| Cognos | 12 |
| Compellent | 12 |
| ComponentOne | 12 |
| CCH | 12 |
| Cisco Systems, Inc. | 13 |
| CCC Information Services | 13 |
| Conexant | 15 |
| Captaris | 15 |
| Cosmi | 19 |
| CCH Tax and Accounting. A WoltersKluwer Company | 20 |