| Adfuel | |
| AdGate Media | |
| AdGlare | |
| Adgraph Design | California |
| Adhancer | California |
| AdHawk | New York |
| AdhereTech | |
| AdhereTech, Inc. | New York |
| Adhezion Biomedical | Pennsylvania |
| ADI Computer Solutions | Arizona |
| Adiant | New Jersey |
| Adicet Bio | California |
| Adicio | California |
| Adient Medical, Inc. | Texas |
| Adimab, LLC | New Hampshire |
| Adina R&D, Inc. | Massachusetts |
| AdInfusion | |
| ADInstruments | Colorado |
| Adioma | California |
| Adionics | |
| Adipo Therapeutics | |
| Adirondack Networks, Inc. | New York |
| Adirondack Online Services, LLC | |
| Adirondack Trust Company | |
| Adiso Therapeutics | |
| Adistec | Florida |
| Adit | Texas |
| Adit Software | New York |
| Aditude, Inc. | New York |
| Aditx, Inc. | Virginia |
| Adium | Florida |
| Adjective & Co. | |
| Adjuvant Partners, LLC | Maryland |
| Adkad Technologies, Inc. | Colorado |
| Adkins Technologies | Colorado |
| ADL Data Systems, Inc. | New York |
| Adler University | Illinois |
| AdLib, Inc. | Washington |
| AdLift | California |
| Adlucent | Texas |
| Adlumin, Inc. | |
| Adly | California |
| ADM Tronics Unlimited, Inc. | New Jersey |
| ADMA Biologics, Inc. | New Jersey |
| Admail.net | Ohio |
| Admanity, LLC | |
| Admark Digital | |
| adMarketplace | New York |
| AdMedia | California |
| Admera Health | New Jersey |