| Chemovator GmbH | |
| Cherry Ventures | Berlin |
| Ches IT Service GmbH | Hesse |
| Chilinet Solutions GmbH | |
| CHIP Xonio Online GmbH | Bavaria |
| CHIP-FLIP | Bavaria |
| Chipcon Systems GmbH | Bavaria |
| Chirai GbR | Bavaria |
| Chives | Hesse |
| CHM.Digital GmbH | |
| Choco Communications GmbH | |
| Chris Heilmann | Berlin |
| Christa Siebes und Lorenz Hölscher Software-Service GbR | North Rhine-Westphalia |
| Christian Adolphy Consulting | Hesse |
| Christian Beier | Brandenburg |
| Christian Borchardt Informatik | North Rhine-Westphalia |
| Christian Ehrhart | North Rhine-Westphalia |
| Christian Jäger Webdesign | Baden-Württemberg |
| Christian Koenen GmbH | |
| Christian Schmidt - Computerservice | Rhineland-Palatinate |
| Christian Schmitz Software GmbH | Rhineland-Palatinate |
| Christian-Albrechts-Universität zu Kiel | Schleswig-Holstein |
| Christian-Albrechts-Universität zu Kiel - Institut für Informatik | Schleswig-Holstein |
| Christian-Albrechts-Universität zu Kiel - Mathematisches Seminar | Schleswig-Holstein |
| Christian-Albrechts-University of Kiel - Information and Coding Theory Lab | Schleswig-Holstein |
| Christliche Internet Dienst GmbH | Berlin |
| Christoph Göbel | |
| Christoph Schubert | Bavaria |
| Chromasoft GmbH | Rhineland-Palatinate |
| Chudovo | |
| CHZ-Soft | Lower Saxony |
| CIB software GmbH | Bavaria |
| Cibait AG | Saarland |
| CID GmbH | Hesse |
| CIDEON Holding GmbH & Co. KG | North Rhine-Westphalia |
| CiJu GmbH | Berlin |
| Cilian AG | |
| cimt AG | Hamburg |
| Cineflight GmbH | |
| Cinemo GmbH | |
| Cinference GmbH | |
| Cinteg AG | Baden-Württemberg |
| CINTEG Design Solutions GmbH | Baden-Württemberg |
| CipSoft GmbH | Bavaria |
| Circadian Technologies GmbH | |
| Circle Unlimited AG | Schleswig-Holstein |
| Circula GmbH | |
| circular.fashion | |
| CircularTree | |
| Circulee GmbH | |