| MarkLogic | California |
| MarkMonitor, Inc. | California |
| Marknet Group | Connecticut |
| Markopolo.ai | Wyoming |
| Markosoft | Arkansas |
| Markovate, Inc. | |
| Marks Media | |
| Markstein | |
| Marktech Optoelectronics | New York |
| MarkTechPost, LLC | California |
| Markup AI | |
| Markup Factory | Iowa |
| MarkUp, Inc. | |
| Markzware, Inc. | California |
| MARL 5G Accelerator | California |
| Marlabs, Inc. | New Jersey |
| Marlex Pharmaceuticals, Inc. | |
| Marlin Connections | |
| Marlin Consulting Solutions | |
| Marlin Management Company, LLC | |
| Marlton Computer Services | New Jersey |
| Marman Industries, Inc. | California |
| Maroon Venture Partners, LLC | Massachusetts |
| Marotta Controls, Inc. | |
| Marq Vision, Inc. | |
| Marqeta, Inc. | California |
| Marquette Adams Telephone Cooperative, Inc. | Wisconsin |
| Marquette University Computer Science | Wisconsin |
| Marquette University Mathematical and Statistical Sciences | Wisconsin |
| Marquis | Texas |
| Marquis Data | Indiana |
| Marr Software, LLC | Wyoming |
| Marro | |
| Marrow Access Technologies | |
| MARS - SalesFocus Solutions | California |
| MARS Antennas and RF Systems Ltd | Illinois |
| Mars Hill University | North Carolina |
| Mars Hill University Computer Science | North Carolina |
| Mars Initiative | |
| Mars United | |
| Marsh Electronics, Inc. | Wisconsin |
| Marsh, LLC | |
| Marshad Technology Group | New York |
| Marshall B. Ketchum University | California |
| Marshall Business Solutions | Georgia |
| Marshall Data Systems | Alabama |
| Marshall Electronics, Inc. | California |
| Marshall Graphics Systems | Tennessee |
| Marshall Marketing | Pennsylvania |
| Marshall Resources, Inc. | Arizona |