| CargoSoft GmbH | Bremen |
| CARIAD | |
| Carinopharm GmbH | |
| Cariqa | |
| Carl Finance GmbH | |
| Carl von Ossietzky Universität Oldenburg | |
| Carl von Ossietzky Universität Oldenburg - Department für Informatik | Lower Saxony |
| Carl Zeiss AG | Baden-Württemberg |
| Carl-von-Ossietzky-Universität Oldenburg - Institut für Mathematik | Lower Saxony |
| Caro.one | Berlin |
| Carr Consulting GmbH | Rhineland-Palatinate |
| Carré Mobility GmbH | |
| Carsig Automotive GbR | Baden-Württemberg |
| Carsten Zöhrer | North Rhine-Westphalia |
| Carstens WebServices | Lower Saxony |
| Caruso GmbH | |
| CAS Software AG | Baden-Württemberg |
| Casadomus AG | Baden-Württemberg |
| Casana GmbH | Bavaria |
| casavi GmbH | |
| Casco Schoeller GmbH | |
| Case Corporate Finance | |
| Case One GmbH | Lower Saxony |
| case-team | North Rhine-Westphalia |
| CaseKing | Berlin |
| CashCape | |
| Cashlink Technologies GmbH | |
| Cashrain | |
| CASIO Europe GmbH | Schleswig-Holstein |
| CASO Systemhaus MOTIVA | Bavaria |
| Caspar Health | |
| Caspari-Software | Hesse |
| Castellan Software Entwicklung GmbH | North Rhine-Westphalia |
| castLabs | |
| CatalYm GmbH | |
| Catchup Applications KG | |
| Categis GmbH | Berlin |
| Catena Capital GmbH | |
| CATHAGO Technology UG (haftungsbeschränkt) | Berlin |
| Catix GmbH | Baden-Württemberg |
| catkin GmbH | |
| Catmedia | Saarland |
| Catuno GmbH | Baden-Württemberg |
| Caudillo GbR | Baden-Württemberg |
| Caught | Baden-Württemberg |
| Caupo.Net | Baden-Württemberg |
| Cavalry | |
| Cavalry Ventures Management GmbH | |
| Cavea Shop | Lower Saxony |
| Cavok | |