| Groups (developers) | Abbr. | Country | City | Rating | |
|---|---|---|---|---|---|
| Amanda Systems | 0.00 ±0.0 | ||||
| AMC Verlag | Germany | 0.00 ±0.0 | |||
| Amdek Corporation | United States | 0.00 ±0.0 | |||
| American Eagle Software | 0.00 ±0.0 | ||||
| Amiga | 0.00 ±0.0 | ||||
| Amulet Enterprises | 0.00 ±0.0 | ||||
| ANALOG 400/800 Corp. | 0.00 ±0.0 | ||||
| ANALOG Computing | United States | 0.00 ±0.0 | |||
| Andreasfilm | 0.00 ±0.0 | ||||
| Angelsoft, Inc. | 0.00 ±0.0 | ||||
| Animals | 0.00 ±0.0 | ||||
| Animkomials | Poland | 0.00 ±0.0 | |||
| Anonymous Atarians | Poland | Turek | 0.00 ±0.0 | ||
| Anonymous AtariOnline users | 0.00 ±0.0 | ||||
| Anschuetz | 0.00 ±0.0 | ||||
| Antic Magazine | 0.00 ±0.0 | ||||
| Antic Publishing, Inc. | 0.00 ±0.0 | ||||
| Antic Software | 0.00 ±0.0 | ||||
| AnticShop | Poland | Cracow (Kraków) | 0.00 ±0.0 | ||
| Antist Software | 0.00 ±0.0 |