| Athena Security, Inc. | Texas |
| athenahealth | Massachusetts |
| AthenaRMS | California |
| Athenaworks | |
| Athenix, Inc. | |
| Athens Group | Texas |
| Athens Microcomputer Center, Inc. | Georgia |
| Athens Research and Technology, Inc. | Georgia |
| Athens State University | Alabama |
| Athens Technical College | Georgia |
| AthensGuy.com | Georgia |
| Athentic AI | |
| Atherion Bioresearch | Ohio |
| Athersys, Inc. | Ohio |
| Athina AI | |
| Athinia | Massachusetts |
| Athletepreneur | Illinois |
| Athlure | |
| AtHomeNet | Colorado |
| Athos Commerce | |
| Athos Silicon, Inc. | |
| Athos Therapeutics, Inc. | |
| Athyrium Capital Management, L.P. | |
| Athyrium Capital Management, L.P. | |
| ATI College | California |
| ATI Consulting | Michigan |
| ATI Graphics, Inc. | |
| Ati Motors | |
| ATI Networks, Inc. | Georgia |
| ATi POS | Tennessee |
| ATI Solutions, Inc. | Virginia |
| ATI, Inc. | Texas |
| Atia Vision, Inc. | California |
| Atiba, LLC | Tennessee |
| ATierOne Web Services | South Carolina |
| Atila Biosystems | California |
| Atilus, LLC | Florida |
| Atipa Technologies | Kansas |
| Atisdigital | Georgia |
| Atiwa Computing, Inc. | Texas |
| ATKearny | |
| ATL Software, LLC | |
| Atla AI | |
| Atlanta Biomedical Corporation | |
| Atlanta Computer Solutions | Georgia |
| Atlanta Graphic Design | Georgia |
| Atlanta Hobby Robotic Club | Georgia |
| Atlanta Interactive Marketing Association | Georgia |
| Atlanta IT Service | |
| Atlanta Java Users Group | Georgia |