| Convertigo S.A. | |
| ConvertPDFtoWord.net | Métropole de Lyon |
| ConviSAV | Morbihan |
| CONVIWEB | Bouches-du-Rhône |
| Copem S.A.S. | Val-de-Marne |
| Copiafax | Côte-d'Or |
| Copieur System | Isère |
| Copilot Partners | Paris |
| Copysud | Haute-Garonne |
| Corail Systems | Hauts-de-Seine |
| Coralis | Bouches-du-Rhône |
| Coralline Informatique | Val-de-Marne |
| Core Biogenesis | |
| Core Biogenesis S.A.S. | |
| Core For Tech | |
| Corebridge Systems | Paris |
| CORIM Solutions | Isère |
| Coriware | Haute-Garonne |
| Corma | |
| Cornec S.A.S. | Seine-et-Marne |
| Cornouaille Informatique | Finistère |
| Corse Diffusion Informatique | Haute-Corse |
| Corse Telecom | Corse-du-Sud |
| Corsicaweb | Haute-Corse |
| Corteria Pharmaceuticals | |
| Cortextech | Oise |
| Cortosys | Paris |
| CorWave S.A. | |
| Corwin | Somme |
| CORYENT Conseil | Yvelines |
| Cosa | |
| COSESO Agency | |
| Cosiweb | Haute-Garonne |
| Cosmian | |
| Cosmic Software | Val-de-Marne |
| Cosmo Tech | |
| Cosmopolit | |
| Cosmos Consultants S.A.S. | Paris |
| Cosmosoft | Seine-Saint-Denis |
| Cosoluce | Pyrénées-Atlantiques |
| Cosy.io | Paris |
| COTEP | |
| Côteweb | Alpes-Maritimes |
| Cotranet | Isère |
| Couleur & Connection | Rhône |
| Courcelles Design | Haute-Garonne |
| Cours de maths 78 | Paris |
| CourtBouillon | |
| Courtigo | |
| Cousin Surgery | |