| MDXG | | Surgical & Medical Instruments & Apparatus | 1376339 |
| MDXH | | Services-Medical Laboratories | 1872529 |
| MDY | | - | 936958 |
| MEC | | Metal Forgings & Stampings | 1766368 |
| MED | | Miscellaneous Food Preparations & Kindred Products | 910329 |
| MEDG | | Services-Personal Services | 2022097 |
| MEDP | | Services-Commercial Physical & Biological Research | 1668397 |
| MEG | | Services-Management Consulting Services | 1643615 |
| MEGI | | - | 1855066 |
| MEGL | | Finance Services | 1881472 |
| MEHA | | Medicinal Chemicals & Botanical Products | 1837254 |
| MEHCQ | | Pharmaceutical Preparations | 1804591 |
| MEI | | Electronic Connectors | 65270 |
| MELI | | Services-Business Services, NEC | 1099590 |
| MENS | | Pharmaceutical Preparations | 1954488 |
| MEOH | | Industrial Organic Chemicals | 886977 |
| MEON | | Services-Advertising Agencies | 2059702 |
| MERC | | Pulp Mills | 1333274 |
| MESO | | Biological Products, (No Diagnostic Substances) | 1345099 |
| MET | | Life Insurance | 1099219 |
| META | | Services-Computer Programming, Data Processing, Etc. | 1326801 |
| METC | | Silver Ores | 1687187 |
| METRY | | - | 2073643 |
| MFA | | Real Estate Investment Trusts | 1055160 |
| MFBI | | Savings Institution, Federally Chartered | 2024899 |
| MFC | | Life Insurance | 1086888 |
| MFG | | National Commercial Banks | 1335730 |
| MFGCF | | Metal Mining | 1823255 |
| MFHK | | - | 2080434 |
| MFI | | Services-Computer Programming Services | 1940941 |
| MFIC | | - | 1278752 |
| MFIN | | Finance Services | 1000209 |
| MFM | | - | 801961 |
| MFON | | Services-Prepackaged Software | 1447380 |
| MG | | Services-Engineering Services | 1436126 |
| MGA | | Motor Vehicle Parts & Accessories | 749098 |
| MGAM | | Services-Amusement & Recreation Services | 1886362 |
| MGCLY | | - | 2039784 |
| MGEE | | Electric, Gas & Sanitary Services | 1161728 |
| MGF | | - | 811922 |
| MGIC | | Services-Prepackaged Software | 876779 |
| MGIH | | Commercial Printing | 1903995 |
| MGLD | | Finance Services | 1005101 |
| MGM | | Hotels & Motels | 789570 |
| MGMNF | | - | 1965615 |
| MGN | | Agricultural Prod-Livestock & Animal Specialties | 1995075 |
| MGNC | | Agricultural Services | 1949864 |
| MGNI | | Services-Computer Programming, Data Processing, Etc. | 1595974 |
| MGNO | | Savings Institution, Federally Chartered | 2033615 |
| MGNX | | Pharmaceutical Preparations | 1125345 |
