| Matexcel | Shirley, New York, United States |
| Matsushita Electric Industrial Co. Ltd. | Osaka , Japan |
| Max Planck Institute of Biochemistry | Munich, Germany |
| Maxon Precision Motors Inc. | Burlingame, California, United States |
| MaxStream Inc. | Orem, Utah, United States |
| May-Ruben Technologies | Calgary, Alberta, Canada |
| mc10 Inc. | Cambridge, Massachusetts, United States |
| McCormack & Farrow | Costa Mesa, California, United States |
| McDermott, Will & Emery | Boston, Massachusetts, United States |
| McDonnell Boehnen Hulbert & Berghoff LLP | Chicago, Illinois, United States |