| Metropolitan State University | Minnesota |
| Metropolitan State University of Denver | Colorado |
| MetroStar Corporation | Maryland |
| MetroStar Systems | Virginia |
| Metrotalk, Inc. | Virginia |
| Metrotec | South Carolina |
| MetroTech, LLC | Florida |
| Metrotechs | |
| Metrotek | Florida |
| Metsera, Inc. | |
| MetTel | New York |
| Metuchen Capacitors, Inc. | New Jersey |
| MetVital, Inc. | California |
| Metz Research, LLC | Illinois |
| Metzger Medical | |
| MEV, LLC | California |
| Mevi, Inc. | Colorado |
| Mevion Medical Systems | Massachusetts |
| MeWe | California |
| MexPago | |
| Meyer and Co., LLC | |
| Meyer Tool, Inc. | |
| Meylah Corporation | Washington |
| Mezmeriz, Inc. | New York |
| Mezmo, Inc. | California |
| Mezorn, LLC | |
| Mezzion Pharmaceuticals, Inc. | |
| MF Digital | New York |
| mFax | Nevada |
| MFC Communications | Massachusetts |
| MFE Inspection Solutions, Inc. | |
| MFG | Georgia |
| mFino Ltd | California |
| mFire | California |
| mFluiDx | California |
| MFM Software, Inc. | Ohio |
| MFP Technology Service | Connecticut |
| MFV Partners | |
| Mg Biologics | |
| MG Marketing | |
| MGA Nexus Marketing | |
| mGage | Georgia |
| MGAWEB | Georgia |
| MGB Systems | Missouri |
| MGC Diagnostics Corporation | Minnesota |
| Mgecom, Inc. | North Carolina |
| MGH Marketing & Advertising | |
| MGI Americas, Inc. | California |
| MGM Design | Arizona |
| MGT Computer Solutions | Ohio |