| MUMaricorp Us, LLC | Shell Knob | — | ◇ UNVERIFIED |
| MCMARSfarm Corporation | Overland | — | ◇ UNVERIFIED |
 Mast Technologies, INC | Independence | — | ◇ UNVERIFIED |
| MMMatrix Manufacturing, INC. | Springfield | — | ◇ UNVERIFIED |
| MMMatthews Manufacturing INC. | Saint Louis | — | ◇ UNVERIFIED |
| MSM.b. Sturgis INC. | Maryland Heights | — | ◇ UNVERIFIED |
| MAMcalester Army Ammunition Plant | Fort Leonard Wood | — | ◇ UNVERIFIED |
| MTMcferron Tool and Machine Company | Harrisonville | — | ◇ UNVERIFIED |
| MMMcgregor Manufacturing Company | Ozark | — | ◇ UNVERIFIED |
| MCMere Capital, LLC dba Czar Weld | House Springs | — | ◇ UNVERIFIED |
| MIMerrill Iron & Steel South | Springfield | — | ◇ UNVERIFIED |
| MCMetal Container Corporation Arnold | Arnold | — | ◇ UNVERIFIED |
 Metal Culverts INC. | Jefferson City | — | ◇ UNVERIFIED |
| MFMetal Fabricators of St Louis | Saint Louis | — | ◇ UNVERIFIED |
| MSMetalflex Sales, Inc. | Saint Charles | — | ◇ UNVERIFIED |
| MOMetal One LLC | Lees Summit | — | ◇ UNVERIFIED |
| MSMetal Sales Mfg CORP | Independence | — | ◇ UNVERIFIED |
| MTMetal Tech Midwest Incorporated | Joplin | — | ◇ UNVERIFIED |
| MHMexico Heating Co., INC. | Mexico | — | ◇ UNVERIFIED |
| MSMichael Steiro | Lebanon | — | ◇ UNVERIFIED |
| MFMicro Finish & Coating INC. | Kansas City | — | ◇ UNVERIFIED |
| MCMid Continent Steel & Wire, INC. | Poplar Bluff | — | ◇ UNVERIFIED |
| MMMidwest Manufacturing | Sullivan | — | ◇ UNVERIFIED |
| MMMidwest Metal Finishing Custom Powder Coating | Saint Joseph | — | ◇ UNVERIFIED |
| MMMidwest Metal Works, LLC | Sparta | — | ◇ UNVERIFIED |
| MSMidwest Steel and Rebar LLC | Seymour | — | ◇ UNVERIFIED |
| MWMidwest Window and Door | Springfield | — | ◇ UNVERIFIED |
| MMMike's Machine Shop | Licking | — | ◇ UNVERIFIED |
| MFMissouri Forge INC | Doniphan | — | ◇ UNVERIFIED |
| MOMissouri Ornamental Iron Company, INC. | University City | — | ◇ UNVERIFIED |
| MPMissouri Pressed Metals INC. | Sedalia | — | ◇ UNVERIFIED |
| MRMissouri Rolling Mill-hazelwood | Hazelwood | — | ◇ UNVERIFIED |
| MUMitek USA INC | Saint Charles | — | ◇ UNVERIFIED |
| MMM & M Vehicle CORP | Mexico | — | ◇ UNVERIFIED |
| MDMonet Desauw INC | Fulton | — | ◇ UNVERIFIED |
| MGMpp Group of Companies INC. | Kansas City | — | ◇ UNVERIFIED |
| MIMueller Industries, L.L.C. | Saint Louis | — | ◇ UNVERIFIED |
| MAMuncy Acquisitions | Kansas City | — | ◇ UNVERIFIED |
| NJNew Joules Engineering INC. | Kansas City | — | ◇ UNVERIFIED |
| NENo-mar Enterprises | Fenton | — | ◇ UNVERIFIED |
| NCNooter Corporation | Saint Louis | — | ◇ UNVERIFIED |
| NANorth American Industries Inc.* | Lampe | — | ◇ UNVERIFIED |
| NMNortheast Missouri Machine & Pattern CO | Palmyra | — | ◇ UNVERIFIED |
| NGNorthrop Grumman | Independence | — | ◇ UNVERIFIED |
| OBOerlikon Balzers Coating USA INC | Saint Louis | — | ◇ UNVERIFIED |
| OTOmega Tool CO | Saint Louis | — | ◇ UNVERIFIED |
| OMOn-site Manufactured Buildings LLC | Branson | — | ◇ UNVERIFIED |
| OAOrbital Atk INC. | Independence | — | ◇ UNVERIFIED |
| OCOsage Canoes LLC | Lebanon | — | ◇ UNVERIFIED |
| OBOzark Barge & Dock Service Inc.* | Gravois Mills | — | ◇ UNVERIFIED |
