| Creative360 | Baden-Württemberg |
| CreativeDogDesign | Saxony |
| CreativeNet | Lower Saxony |
| Creativestyle GmbH | |
| Creators by Drees & Sommer SE | |
| Credativ GmbH | North Rhine-Westphalia |
| credia communications GmbH | North Rhine-Westphalia |
| Credibur GmbH | |
| CreditLinks GmbH | |
| credX AG | |
| CRELUX GmbH | |
| Creopard Network & Websolutions | Bavaria |
| Creos Lernideen und Beratung GmbH | North Rhine-Westphalia |
| Criadero GbR | Brandenburg |
| Crispy IT-Solutions GmbH & Co. KG | |
| crisscrossed GmbH | Hesse |
| CRM InformationSystems GmbH | Bavaria |
| crm-now GmbH | Berlin |
| cron-job.org | |
| Cronon GmbH | Berlin |
| Cronsync | Berlin |
| CROSS Solution | |
| crossbase mediasolution GmbH | Baden-Württemberg |
| Crosscan GmbH | |
| Crossconcept GmbH | North Rhine-Westphalia |
| CrossEngage | Berlin |
| CrossLend GmbH | |
| CrossMedia Consulting | |
| CrossVentures GmbH | North Rhine-Westphalia |
| Crowd Guru | Berlin |
| Crowd Technologies GmbH | |
| Crowder | |
| Crowdfox GmbH | |
| Crowdpark Games & Entertainment GmbH | Berlin |
| Crowntronic Kommunikationsberatung | Hamburg |
| CRP Informationssysteme GmbH | Rhineland-Palatinate |
| CRS Clinical Research Services Management GmbH | |
| CRS Clinical Research Services Mannheim GmbH | |
| CRX Markets AG | |
| Cryptomator | North Rhine-Westphalia |
| CryptoMotors UG (haftungsbeschränkt) | Bavaria |
| CryptoPhone | |
| CrystalsFirst | |
| Crytek GmbH | Bavaria |
| CS ComputerService | Rhineland-Palatinate |
| CS Hard & Software Consulting GmbH | Saarland |
| CS Inventory Software | Bavaria |
| CS Stöber | Hesse |
| CS-Informationstechnik | Hesse |
| CS-Multimedia GmbH | Baden-Württemberg |