| MarkStein Software Entwicklungs- und Vertriebs GmbH | Hesse |
| Markt und Standort Beratungsgesellschaft mbH | Bavaria |
| MarktPilot GmbH | |
| Marktstammdatenregister | |
| Markus Friedrich - Datentechnik | Brandenburg |
| Markus Metzger Webentwicklung | North Rhine-Westphalia |
| Markus Software GmbH | North Rhine-Westphalia |
| Marley Communications | Hesse |
| Marmato GmbH | Baden-Württemberg |
| Marquis Automatisierungstechnik GmbH | |
| Mars Solutions GmbH | |
| Marschall Electronics GmbH & Co. KG | Bavaria |
| Marta GmbH | |
| Martes New Media | Baden-Württemberg |
| Martian & Machine GmbH | Berlin |
| Martime Startups Germany | |
| Martin Fabiani | North Rhine-Westphalia |
| Martin Networks | Rhineland-Palatinate |
| Martin-Luther-Universität Halle-Wittenberg | |
| Martin-Luther-Universität Halle-Wittenberg - Institut für Informatik | Saxony-Anhalt |
| Martin-Luther-Universität Halle-Wittenberg - Institut für Mathematik | Saxony-Anhalt |
| Marvel Fusion GmbH | |
| Marvest GmbH | |
| Marx Softwareentwicklung | Bavaria |
| Marxmeier Software AG | North Rhine-Westphalia |
| März Datenverarbeitungs GmbH | Bavaria |
| März Internetwork Services AG | North Rhine-Westphalia |
| Marzahn Online | Berlin |
| MAS Elektronik AG | Lower Saxony |
| MAS Software GmbH | Bavaria |
| Masa Advertising | North Rhine-Westphalia |
| Masktech GmbH | Bavaria |
| MaSoft e.K. | North Rhine-Westphalia |
| Massandra eBusiness Engineering GmbH | Hesse |
| MAST Hard- & Software | Baden-Württemberg |
| Master of Search | |
| MasterBootRecord.de | Bavaria |
| masterplan IT GmbH | Saxony |
| Masters Consulting GmbH | Schleswig-Holstein |
| Mastodon gGmbH | |
| Mastro-IT | Baden-Württemberg |
| MASYS GmbH | Hamburg |
| match.care GmbH | |
| matchingIT GmbH | North Rhine-Westphalia |
| Matchory GmbH | |
| matelso GmbH | |
| Mateo Estate GmbH | |
| materialboerse.de GmbH | Lower Saxony |
| Materna Information & Communications SE | North Rhine-Westphalia |
| Math2Market GmbH | Rhineland-Palatinate |