| MMMartin Manufactuirng, INC. | Sapulpa | OK | — | ◇ UNVERIFIED |
| MHMartin-Pittman Holdings, Inc. | Indianapolis | IN | — | ◇ UNVERIFIED |
| MSMartin Steel Constructors | Eleele | HI | — | ◇ UNVERIFIED |
| MSMartin Steel INC | Huntington | WV | — | ◇ UNVERIFIED |
| MWMartin Welding and Fabrication LLC | Contoocook | NH | — | ◇ UNVERIFIED |
| MSMaryland Structural Fabricators INC | Millington | MD | — | ◇ UNVERIFIED |
| MLMascoat LLC | West Monroe | LA | — | ◇ UNVERIFIED |
| MHMascotte Home Security Products INC | Portland | OR | — | ◇ UNVERIFIED |
| MFMas Fab, Incorporated Dba Formit Steel Company | Red Lion | PA | — | ◇ UNVERIFIED |
| MSMason Structural Steel INC. | Walton Hills | OH | — | ◇ UNVERIFIED |
| MWMason West, INC | Placentia | CA | — | ◇ UNVERIFIED |
| MWMaspeth Welding, INC | New York | NY | — | ◇ UNVERIFIED |
| MMMass Machine & Fabricating Company | Washington | PA | — | ◇ UNVERIFIED |
| MMMatcor Metal Fabrication | Morton | IL | — | ◇ UNVERIFIED |
| MCMaterial Control Systems, INC. | Cordova | IL | — | ◇ UNVERIFIED |
| MHMaterial Handling Technologies, INC. | North Syracuse | NY | — | ◇ UNVERIFIED |
| MRMaterial Resources INC | Forest Grove | OR | — | ◇ UNVERIFIED |
| MIMattei, INC. | Harlingen | TX | — | ◇ UNVERIFIED |
| MIMattessich Iron, LLC | Memphis | NY | — | ◇ UNVERIFIED |
| MIMattessich Iron, LLC | Baldwinsville | NY | — | ◇ UNVERIFIED |
| MBMatthew Bronze West Annex Facility | Kingwood | WV | — | ◇ UNVERIFIED |
 Matthews International Corporation | Kingwood | WV | — | ◇ UNVERIFIED |
| MBMaura Buildings, Incorporated | Lebanon | PA | — | ◇ UNVERIFIED |
| MMMaurice Mesple Dba Mesples Machine Shop and Pump | Fresno | CA | — | ◇ UNVERIFIED |
| MCMauser Container Services | Blacklick | OH | — | ◇ UNVERIFIED |
| MIMaxanns INC | Greeley | CO | — | ◇ UNVERIFIED |
| MSMay Specialty Fabricators, INC. | Register | GA | — | ◇ UNVERIFIED |
 Mayville Engineering Company INC Dba Mec | Vanderbilt | MI | — | ◇ UNVERIFIED |
| MWMazzella Welding & Fabrication INC | Wellsburg | WV | — | ◇ UNVERIFIED |
| MEMbm Enterprises, INC. | Pleasant Plains | AR | — | ◇ UNVERIFIED |
| MSM&b Steel Fabricators, INC. | Orlando | FL | — | ◇ UNVERIFIED |
| MAMcabee Assembly Facility | Tuscaloosa | AL | — | ◇ UNVERIFIED |
| MMMcadams & Mcadams, INC. D/b/a M & M Welding | Archdale | NC | — | ◇ UNVERIFIED |
| MWMcbrides Welding Dba American Iron | Ridgecrest | CA | — | ◇ UNVERIFIED |
| MSMcb Steel, INC. | Bessemer | AL | — | ◇ UNVERIFIED |
| MIMcclister INC | Tualatin | OR | — | ◇ UNVERIFIED |
| MIMcdermott INC | Gibson | LA | — | ◇ UNVERIFIED |
| MIMcdermott INC - Morgan City Fabrication Facility - Amelia Yard | Amelia | LA | — | ◇ UNVERIFIED |
| MMMcdonough Marine Service | Metairie | LA | — | ◇ UNVERIFIED |
| MMMcelroy Metal Mill INC | Monroe | LA | — | ◇ UNVERIFIED |
| MMMcelroy Metal Mill INC Dba Mcelroy Metal | Adelanto | CA | — | ◇ UNVERIFIED |
| MTMce Technologies INC | Seattle | WA | — | ◇ UNVERIFIED |
| MLMcewen Lighting Studio | Berkeley | CA | — | ◇ UNVERIFIED |
| MMMcfarlane Mfg CO | Sauk City | WI | — | ◇ UNVERIFIED |
| MIMcgregor Ind Inc/dunmore Plt | Dunmore | PA | — | ◇ UNVERIFIED |
| MHMckee Holdings LLC | Sandy | OR | — | ◇ UNVERIFIED |
 Mclaughlin Body CO | East Moline | IL | — | ◇ UNVERIFIED |
| MSMcmahno Steel CO | Chula Vista | CA | — | ◇ UNVERIFIED |
| MFMcm Fabricators, INC. Dba Global Fabricators | Shafter | CA | — | ◇ UNVERIFIED |
| MSMcneely Steel & Supply | Leavenworth | KS | — | ◇ UNVERIFIED |
| MCMcnichols Company | Garland | TX | — | ◇ UNVERIFIED |
| MIMcReynolds Investments LLC | Waterford | WI | — | ◇ UNVERIFIED |
| MMMcswain Metal Fabrication, INC. | Englewood | CO | — | ◇ UNVERIFIED |
| MSMcwhirter Steel | Lancaster | CA | — | ◇ UNVERIFIED |
| MCMDI Corporation | Cheney | KS | — | ◇ UNVERIFIED |
| MCMDI Corporation | Cheney | KS | — | ◇ UNVERIFIED |
 Meadow-burke Products | Hazleton | PA | — | ◇ UNVERIFIED |
| MGMec General Construction INC. | Brooklyn | NY | — | ◇ UNVERIFIED |
| MGMec General Construction INC. | Brooklyn | NY | — | ◇ UNVERIFIED |
| MAMechanical and Industrial Steel Services, INC. | Channahon | IL | — | ◇ UNVERIFIED |
| MHMedway Hall Development Group, Inc. | Jacksonville | FL | — | ◇ UNVERIFIED |
| MMMeiers Modern Metals, LLC | Portland | OR | — | ◇ UNVERIFIED |
| MPMellies Products INC. | Morganville | KS | — | ◇ UNVERIFIED |
| MMMelrose Metal Products, INC | Fremont | CA | — | ◇ UNVERIFIED |
| MPMelting Point Welding & Fabrication, Inc. | Killingly | CT | — | ◇ UNVERIFIED |
| MBMelvin Baltodano | Ontario | CA | — | ◇ UNVERIFIED |
| MWMelvin Wrought Iron & Ornamental | Ontario | CA | — | ◇ UNVERIFIED |
| MSMemphis Sheet Metal Works INC | Memphis | TN | — | ◇ UNVERIFIED |
| MMMenard Manufacturing INC. | Dewitt | AR | — | ◇ UNVERIFIED |
| MMMenator Metal Works LLC | Winneconne | WI | — | ◇ UNVERIFIED |
| MSMendel Steel & Ornamental Iron Company | Bethel Park | PA | — | ◇ UNVERIFIED |
| MOMendoza's Ornamental Iron | Fullerton | CA | — | ◇ UNVERIFIED |
| MMMerchants Metals, LLC | Jacksonville | FL | — | ◇ UNVERIFIED |
| MMMerchant's Moving & Storage Corporation | Yoakum | TX | — | ◇ UNVERIFIED |
| MCMere Capital, LLC dba Czar Weld | House Springs | MO | — | ◇ UNVERIFIED |
| MSMeridian Specialty Vehicles | Las Vegas | NV | — | ◇ UNVERIFIED |
| MEMerrill Engineering & Integration | Saginaw | MI | — | ◇ UNVERIFIED |
| MFMerrill Fab | Merrill | WI | — | ◇ UNVERIFIED |
| MIMerrill Iron & Steel South | Springfield | MO | — | ◇ UNVERIFIED |
| MSMerrill Steel Camanche | Camanche | IA | — | ◇ UNVERIFIED |
| MCMerrimack County Customs, LLC. | Bradford | NH | — | ◇ UNVERIFIED |
| MVMesilla Valley Metals | Las Cruces | NM | — | ◇ UNVERIFIED |
| MMMesser Machine - Mfg INC | Windom | MN | — | ◇ UNVERIFIED |
| MDMeta Designs, LLC | Salt Lake City | UT | — | ◇ UNVERIFIED |
| MAMetal Air Ironworks, INC. | Chico | CA | — | ◇ UNVERIFIED |
| MAMetal Alliance Inc | Huntingdon Valley | PA | — | ◇ UNVERIFIED |
| MAMetal Arts Engravers INC | Shawnee | KS | — | ◇ UNVERIFIED |
| MBMetal Bending Corporation | Orange | CA | — | ◇ UNVERIFIED |
| MLMetalbuilt LLC | Macomb | MI | — | ◇ UNVERIFIED |
| MCMetal Concepts Az LLC | Phoenix | AZ | — | ◇ UNVERIFIED |
| MCMetal Concepts LLC | Cypress | TX | — | ◇ UNVERIFIED |
| MIMetal-con, INC. | Sylvania | GA | — | ◇ UNVERIFIED |
| MCMetal Container Corporation | Oklahoma City | OK | — | ◇ UNVERIFIED |
| MLMetalCraft LLC | Bantam | CT | — | ◇ UNVERIFIED |
| MDMetal Design Corporation | Madison | WI | — | ◇ UNVERIFIED |
| MEMetal Enterprises, INC. | Portland | OR | — | ◇ UNVERIFIED |
| MAMetalfab Arizona L.l.c. | Phoenix | AZ | — | ◇ UNVERIFIED |
| MIMetalfab INC | Richland | WA | — | ◇ UNVERIFIED |
| MIMetalfab INC | Kennewick | WA | — | ◇ UNVERIFIED |
| MIMetalfab, INC. | San Antonio | FL | — | ◇ UNVERIFIED |
