| MMMetso Minerals Industries INC | Birmingham | AL | Primary Metal Manufacturing331513 | — | ◇ UNVERIFIED |
| MOMetso Outotec USA INC | Warrenton | MO | Primary Metal Manufacturing331513 | — | ◇ UNVERIFIED |
| MLMht Luxury Alloys192 | Compton | CA | Primary Metal Manufacturing331521 | — | ◇ UNVERIFIED |
| MCMichels & CO Furniture Mfg | Lynwood | CA | Primary Metal Manufacturing331221 | — | ◇ UNVERIFIED |
| MEMich Extruded Aluminum-jackson | Jackson | MI | Primary Metal Manufacturing331316 | — | ◇ UNVERIFIED |
| MSMichigan Steel, INC. | Muskegon | MI | Primary Metal Manufacturing331513 | — | ◇ UNVERIFIED |
| MIMicro Industries INC | Rock Falls | IL | Primary Metal Manufacturing331522 | — | ◇ UNVERIFIED |
| MMMid-am Metal Forming, INC. | Rogersville | MO | Primary Metal Manufacturing331491 | — | ◇ UNVERIFIED |
| MIMidco Industries | Saint Louis | MO | Primary Metal Manufacturing331528 | — | ◇ UNVERIFIED |
| MCMid-continent Coal & Coke | Portage | IN | Primary Metal Manufacturing331110 | — | ◇ UNVERIFIED |
| MMMid-south Metals Incorporated | Greenville | NC | Primary Metal Manufacturing331492 | — | ◇ UNVERIFIED |
| MAMidwest Alloys Foundry | O Fallon | MO | Primary Metal Manufacturing331513 | — | ◇ UNVERIFIED |
| MDMidwest Dicken Fndy | Arcadia | OH | Primary Metal Manufacturing331525 | — | ◇ UNVERIFIED |
| MFMidwest Fabrication and Steel LLC | Pueblo | CO | Primary Metal Manufacturing331513 | — | ◇ UNVERIFIED |
| MMMidwest Metallurgical Laboratory Site | Marshall | MI | Primary Metal Manufacturing331511 | — | ◇ UNVERIFIED |
| MMMid-west Metal Products | Muncie | IN | Primary Metal Manufacturing331222 | — | ◇ UNVERIFIED |
| MWMid West Wire Products INC | Ferndale | MI | Primary Metal Manufacturing331111 | — | ◇ UNVERIFIED |
| MHMile Hi Metal Foundry | Denver | CO | Primary Metal Manufacturing331524 | — | ◇ UNVERIFIED |
| MMMillbank Materials USA | Portland | OR | Primary Metal Manufacturing331319 | — | ◇ UNVERIFIED |
| MSMil Spe Magnetics INC | Pomona | CA | Primary Metal Manufacturing331110 | — | ◇ UNVERIFIED |
| MRMiltec Resources Uss Edgar Thomson Works | Braddock | PA | Primary Metal Manufacturing331110 | — | ◇ UNVERIFIED |
| MGMilwaukee Gray Iron, LLC | West Allis | WI | Primary Metal Manufacturing331510 | — | ◇ UNVERIFIED |
| MSMissouri Steel Castings Incorporated | Joplin | MO | Primary Metal Manufacturing331513 | — | ◇ UNVERIFIED |
| MZMitsui Zinc Powder | Monaca | PA | Primary Metal Manufacturing331410 | — | ◇ UNVERIFIED |
| MWMi Windows and Doors | Carrollton | TX | Primary Metal Manufacturing331316 | — | ◇ UNVERIFIED |
| MMMk Metalfoils USA INC | Duncan | SC | Primary Metal Manufacturing331221 | — | ◇ UNVERIFIED |
| MPMmi Products INC | Bartonville | IL | Primary Metal Manufacturing331222 | — | ◇ UNVERIFIED |
| MAModern Art Services | Long Island City | NY | Primary Metal Manufacturing331410 | — | ◇ UNVERIFIED |
| MDModern Die Casting CORP | Chicago | IL | Primary Metal Manufacturing331521 | — | ◇ UNVERIFIED |
| MPModern Pattern & Foundry CO. INC. (mp) | Vernon | CA | Primary Metal Manufacturing331513 | — | ◇ UNVERIFIED |
| MMMoment Metal LLC | Albany | NY | Primary Metal Manufacturing331513 | — | ◇ UNVERIFIED |
| MAMonarch Aluminum Casting CO | South Gate | CA | Primary Metal Manufacturing331524 | — | ◇ UNVERIFIED |
| MSMoreys Salvage & Glass | Windsor | CO | Primary Metal Manufacturing331492 | — | ◇ UNVERIFIED |
| MTMorris Tick CO INC | Bloomington | IL | Primary Metal Manufacturing331315 | — | ◇ UNVERIFIED |
| MFMorrow Foundry | Coffeyville | KS | Primary Metal Manufacturing331492 | — | ◇ UNVERIFIED |
| MSMorton Salt INC - Weeks Island Facility | New Iberia | LA | Primary Metal Manufacturing331512 | — | ◇ UNVERIFIED |
| MCMotor Castings CO | Milwaukee | WI | Primary Metal Manufacturing331510 | — | ◇ UNVERIFIED |
| MCMpa - Cox Creek | Baltimore | MD | Primary Metal Manufacturing331000 | — | ◇ UNVERIFIED |
| MPM Pashelinsky & Sons | Jersey City | NJ | Primary Metal Manufacturing331419 | — | ◇ UNVERIFIED |
| MIMp Industries, INC. | O'fallon | MO | Primary Metal Manufacturing331511 | — | ◇ UNVERIFIED |
| MIMubea INC | Florence | KY | Primary Metal Manufacturing331221 | — | ◇ UNVERIFIED |
| MCMueller Casting CO INC | Fulton | MS | Primary Metal Manufacturing331525 | — | ◇ UNVERIFIED |
| MCMunicipal Castings INC | Madison | MN | Primary Metal Manufacturing331511 | — | ◇ UNVERIFIED |
| MCMuskegon Castings Corporation/port City Metal Products | Muskegon | MI | Primary Metal Manufacturing331523 | — | ◇ UNVERIFIED |
| MMMutual Metals, INC. | Providence | RI | Primary Metal Manufacturing331492 | — | ◇ UNVERIFIED |
| MWMws Wire Industries | Westlake Village | CA | Primary Metal Manufacturing331422 | — | ◇ UNVERIFIED |
| NCNashtec Corpus Christi Plant | Gregory | TX | Primary Metal Manufacturing331313 | — | ◇ UNVERIFIED |
| NANational Aluminum Brass Foundry INC | Independence | MO | Primary Metal Manufacturing331522 | — | ◇ UNVERIFIED |
| NMNational Metal Abrasive Company | Wadsworth | OH | Primary Metal Manufacturing331513 | — | ◇ UNVERIFIED |
| NMNational Metals INC | Leeds | AL | Primary Metal Manufacturing331000 | — | ◇ UNVERIFIED |
