| MacroFab, Inc. | |
| MacroGenics, Inc. | Maryland |
| MacroHype | |
| MacroLogic, Inc. | Missouri |
| Macrometa | California |
| Macromicro, LLC | |
| Macromoltek, Inc. | |
| Macron Dynamics, Inc. | Pennsylvania |
| Macrophage Therapeutics, Inc. | |
| Macroplant, LLC | Massachusetts |
| Macrosoft, Inc. | New Jersey |
| MacroSolutions | |
| MacroSystem US, Inc. | Colorado |
| Macrotope, Inc. | |
| Macrotron Systems, Inc. | California |
| Macrumors.com, LLC | Virginia |
| Macs at Work, Inc. | Massachusetts |
| MacScripter | Texas |
| MacSolutions Plus, Inc. | New York |
| MacSpecialist, Inc. | Virginia |
| MacSTAC | New York |
| MacStadium, Inc. | Georgia |
| MacStories, Inc. | |
| MacTech Solutions, LLC | Texas |
| MacTechs | Washington |
| MacTLC | Texas |
| Mactrast, LLC | California |
| MacUSA.net | Illinois |
| MacVector, Inc. | North Carolina |
| Macware, Inc. | Nebraska |
| Macwest Data Recovery | California |
| Macworld | California |
| Mad City Techs | Wisconsin |
| MAD Development | |
| Mad Fish Digital, Inc. | Oregon |
| Mad House | Delaware |
| Mad Men Marketing | |
| Mad Mimi | New York |
| Mad Mobile | Florida |
| Mad Monkey Media, Inc. | |
| Mad Mouse Creative | |
| Mad Otter Games | Oregon |
| Mad Scientist Software, Inc. | Utah |
| Mad Street Den, Inc. | California |
| MadCap Software, Inc. | California |
| Madden Creative | |
| Maddox Defense | |
| Made in Fort Worth | |
| Made Scientific | |
| Made to Order Software Corporation | California |