| Abstract Studio Design, Inc. | |
| Abstract Technology Group | Indiana |
| Abstracta | |
| Abstraction Consulting Co. | Georgia |
| ABSTRAKT Corporation | Arizona |
| Abstrax Web, LLC | |
| Absyz, Inc. | Michigan |
| Abt Global | |
| Abterra Biosciences | California |
| AbTherx | California |
| Abundance Partners, LLC | New York |
| Abundant Computer Services, LLC | Florida |
| Abundant Robotics, Inc. | California |
| AbuseIPDB, LLC | |
| Abusix, Inc. | Massachusetts |
| AbVacc | Maryland |
| Abvance Therapeutics | |
| Abveris | Massachusetts |
| Abyrx, Inc. | |
| Abyssinia Biologics, Inc. | |
| ABZ, Inc. | Virginia |
| Abzyme Therapeutics, LLC | |
| AC Consulting | California |
| AC Lion | New York |
| AC Photonics, Inc. | California |
| AC Strategic Marketing | |
| AC&M Group | |
| AC2, Inc. | Texas |
| ACA Computer Integrators, Inc. | Massachusetts |
| ACA Group | |
| ACA Systems | Minnesota |
| ACA Technologies, Inc. | New Jersey |
| ACA WEB Consulting | California |
| Acacia Communications, Inc. | Massachusetts |
| Acacia Systems | California |
| ACAD-Plus, Inc. | Texas |
| Acadaca | New York |
| Academe Solutions | Maine |
| Academic Approach | |
| Academic Software, Inc. | Kentucky |
| Academic Web Pages | Massachusetts |
| AcademicSuperstore.com | Texas |
| Academize | |
| Academy College | Minnesota |
| Academy Communications | Ohio |
| Academy for Radiology & Biomedical Imaging Research | |
| Academy of Interactive Arts & Sciences | California |
| Academy Pittsburgh, LLC | Pennsylvania |
| Academy Software Foundation | California |
| AcademyX, Inc. | California |