| MPMetal Pros | Wichita | KS | — | ◇ UNVERIFIED |
| MPMetals & Plastics INC | Longwood | FL | — | ◇ UNVERIFIED |
| MUMetals USA Mobile | Mobile | AL | — | ◇ UNVERIFIED |
| MIMetaltech Industries INC | Longmont | CO | — | ◇ UNVERIFIED |
| MSMetropolitan Steel I/steelco | Sinking Spring | PA | — | ◇ UNVERIFIED |
| MMMetso Minerals | Milwaukee | WI | — | ◇ UNVERIFIED |
| MUMeyer Utility Structures | Clinton | IL | — | ◇ UNVERIFIED |
| MAMfs Arz | Phoenix | AZ | — | ◇ UNVERIFIED |
| MGM & G Duravent INC | Vacaville | CA | — | ◇ UNVERIFIED |
| MAMichael Anthony Jewelers Incorporated | Mount Vernon | NY | — | ◇ UNVERIFIED |
| MWMichigan Wire Die | Warren | MI | — | ◇ UNVERIFIED |
| MAMid America Steel Inc-fargo | Fargo | ND | — | ◇ UNVERIFIED |
| MAMiddle Atlantic Products, INC. | Fairfield | NJ | — | ◇ UNVERIFIED |
| MMMidland Metals Products | Chicago | IL | — | ◇ UNVERIFIED |
| MIMid-park INC - Mid-park Highway | Leitchfield | KY | — | ◇ UNVERIFIED |
| MFMid-south Fabrications INC | Jemison | AL | — | ◇ UNVERIFIED |
| MSMid States Steel Products CO | Lexington | KY | — | ◇ UNVERIFIED |
| MSMidstate Steel, INC. | Macon | GA | — | ◇ UNVERIFIED |
| MSMidwestern Steel Fabricators Chicago LLC | Hammond | IN | — | ◇ UNVERIFIED |
| MIMidwest Industrial Metals | Northlake | IL | — | ◇ UNVERIFIED |
| MMMidwest Machine Products INC | Golden | CO | — | ◇ UNVERIFIED |
| MFMikes Fabricating Incorporated | Moody | AL | — | ◇ UNVERIFIED |
| MIMiller/greeneville INC. | Greeneville | TN | — | ◇ UNVERIFIED |
| MIMiller Industrial | Kokomo | IN | — | ◇ UNVERIFIED |
| MFMillers Fab & Weld Corporation | Riverside | CA | — | ◇ UNVERIFIED |
| MFMillinocket Fabrication & Machine INC | Millinocket | ME | — | ◇ UNVERIFIED |
| MCMills CO | Upper Sandusky | OH | — | ◇ UNVERIFIED |
 Mills Manufacturing INC | Earlville | IA | — | ◇ UNVERIFIED |
| MUMinova USA INC | South Point | OH | — | ◇ UNVERIFIED |
| MMMisener Marine Construction, INC. | Tampa | FL | — | ◇ UNVERIFIED |
| MDMissouri Dry Dock & Repair CO | Cape Girardeau | MO | — | ◇ UNVERIFIED |
| MVMissouri Valley Steel Company | Sioux City | IA | — | ◇ UNVERIFIED |
| MCMjk Custom Fab and Coatings LLC | Ogden | UT | — | ◇ UNVERIFIED |
| MSMka Spray Service | Lawrence | MA | — | ◇ UNVERIFIED |
| MMMk Metal Products Enterprises INC | Mansfield | OH | — | ◇ UNVERIFIED |
| MMModern Mechanical Fabrication INC | Champlain | NY | — | ◇ UNVERIFIED |
| MWModern Welding CO of Kentucky INC | Hardin County | KY | — | ◇ UNVERIFIED |
| MCModineer Coatings Division South | South Bend | IN | — | ◇ UNVERIFIED |
 Modine Manufacturing CO | Clinton | TN | — | ◇ UNVERIFIED |
| MMModine Mfg CO - Former Site of | Washington | IA | — | ◇ UNVERIFIED |
| MWMonarch Ware INC | Algoma | WI | — | ◇ UNVERIFIED |
| MPMonitor Products INC | Hauppauge | NY | — | ◇ UNVERIFIED |
| MIMonti Incorporated | Cincinnati | OH | — | ◇ UNVERIFIED |
| MDMoore Dp, LLC | Lexington | KY | — | ◇ UNVERIFIED |
| MMMoreng Metal Products | Totowa | NJ | — | ◇ UNVERIFIED |
| MPMorgan Products | Valencia | CA | — | ◇ UNVERIFIED |
| MIMoritz International INC. (0370010048) | Mansfield | OH | — | ◇ UNVERIFIED |
| MIMor/ryde International INC | Elkhart | IN | — | ◇ UNVERIFIED |
| MFMountaineer Fabricators INC | Nitro | WV | — | ◇ UNVERIFIED |
| MSMountain States Sheet Metal | Pueblo | CO | — | ◇ UNVERIFIED |
