| Alpha Com Deutschland GmbH | Hamburg |
| Alpha Computer GmbH | Saxony |
| Alpha EDV GmbH | Lower Saxony |
| alpha projekt GbR | Berlin |
| Alpha Search | Hesse |
| alpha Soft | Bavaria |
| alpha-bit GmbH | Bavaria |
| alpha-board GmbH | Berlin |
| Alpha-Soft Computer Security GmbH | Saxony |
| Alphabet Type GmbH | |
| Alphabytes.de | North Rhine-Westphalia |
| Alphacool International GmbH | |
| AlphaCron Datensysteme | Thuringia |
| Alphadata Gesellschaft für Softwareentwicklung, Internet und Beratung mbH | North Rhine-Westphalia |
| alphamerisch Webdesign | Baden-Württemberg |
| AlphaPet Ventures GmbH | Bavaria |
| Alphasoft GmbH | North Rhine-Westphalia |
| Alphasystems GmbH | Bavaria |
| Alphatech Computersysteme GmbH | Bavaria |
| Alphin GmbH | |
| Alpine Electronics (Europe) GmbH | Bavaria |
| Alpine Space Ventures Management GmbH | |
| Alptech Elektronik GmbH | Hesse |
| Alschi-Soft oHG | |
| ALSTIN II GmbH | |
| alta4 AG | Rhineland-Palatinate |
| Altair Engineering GmbH | Baden-Württemberg |
| Altair Systems GmbH | Bavaria |
| Altais Webdesign & Internet Service, M. Schulte-Holtey & P. Knippers GbR | North Rhine-Westphalia |
| Alte Försterei Veranstaltungs GmbH & Co. KG | |
| Altech Advanced Materials AG | |
| Altech GmbH | |
| ALTEN GmbH | |
| ALTER Data GmbH | Baden-Württemberg |
| Alternate GmbH | Hesse |
| Alternate Tools | |
| Alternativ Power Computer | Bavaria |
| Alternative.me | |
| ALTHAUS & JUNKER GmbH | North Rhine-Westphalia |
| Althen GmbH | Hesse |
| Altona Diagnostics GmbH | |
| Altula | North Rhine-Westphalia |
| Alugha GmbH | |
| ALVDIGITAL Systems UG (haftungsbeschraenkt) | |
| Alytas Therapeutics GmbH | |
| AM Ventures Management GmbH | |
| AMAKURA IT eG | North Rhine-Westphalia |
| AMANA consulting GmbH | |
| Amapola GmbH | |
| amaZervice UG (haftungsbeschränkt) | Bavaria |