| Name | Type | Country |
|---|---|---|
| CAF | Enterprise | |
| CBT Comunicación Multimedia | Enterprise | Spain |
| CEIT | Enterprise | Spain |
| Cenker | Enterprise | Spain |
| Centre for Research and Technology HELLAS | Research group | Greece |
| CENTRE TECNOLOGIC DE TELECOMUNICACIONS DE CATALUNYA | Research group | |
| Clúster de Movilidad y Logística de Euskadi | Association | Spain |
| CNIT | Enterprise | France |
| Codognotto | Enterprise | Italy |
| Compañía Mediterránea de Energía Solar | Enterprise | Spain |