| CepNet | |
| CEPRES GmbH | |
| CeramOptec GmbH | North Rhine-Westphalia |
| Cerca Biotech | Berlin |
| Cere Network | |
| Ceritech AG | |
| Certif-ID International GmbH | |
| Certivity GmbH | |
| CESOFT | North Rhine-Westphalia |
| CESYS Gesellschaft für angewandte Mikroelektronik mbH | Bavaria |
| CeTI - Centre for Tactile Internet with Human-in-the-Loop | |
| Ceyoniq Technology GmbH | North Rhine-Westphalia |
| CFgO GmbH | |
| Cfm Oskar Tropitzsch GmbH | |
| cFos Software GmbH | North Rhine-Westphalia |
| CFturbo GmbH | Saxony |
| CFX Berlin Software GmbH | Berlin |
| CG IT-Solutions GmbH | |
| CGM Systemhaus GmbH | |
| CGM Technology Services | Hesse |
| Cgnote GmbH | |
| CGRateS | |
| Chamaeleon AG | Rhineland-Palatinate |
| Channel Guru GmbH | |
| Channel Microelectronic GmbH | |
| Chaos | |
| Chaos Computer Club Cologne e.V. | North Rhine-Westphalia |
| Chaos Computer Club e.V. | Lower Saxony |
| Chaos Computer Club Frankfurt e.V. | Hesse |
| Chaos Computer Club München e.V. | Bavaria |
| Chaos Consulting e.V. | |
| Chargecloud GmbH | |
| ChargeX GmbH | |
| Charging Interface Initiative (CharIN) e. V. | |
| Charité - Universitätsmedizin Berlin | Berlin |
| Charles GmbH | |
| Charly Education | |
| ChartMogul GmbH & Co. KG | |
| Chatbot Summit | |
| ChatPDF GmbH | |
| Chatsystem24.de | Schleswig-Holstein |
| CHC IT-Solutions | SOLVA | Hesse |
| CHD Electronics GmbH | Schleswig-Holstein |
| CHECK24 Ventures GmbH | |
| CHECK5 | Baden-Württemberg |
| Checkdomain GmbH | |
| Checkmk | Bavaria |
| chem IT Services GbR | Bavaria |
| ChemCon GmbH | |
| Chemisch-pharmazeutisches Labor, Rolf Sachse GmbH | |