| MWMetal Works Performance, Inc | Saint Charles | IL | — | ◇ UNVERIFIED |
| MMetco | Hartselle | AL | — | ◇ UNVERIFIED |
| MMMetro Manufacturing INC | Saint Paul | MN | — | ◇ UNVERIFIED |
| MCMetroplex Conveyor & Services, LLC | Quinlan | TX | — | ◇ UNVERIFIED |
| MFMetroplex Fabrication and Erection, LLP | Azle | TX | — | ◇ UNVERIFIED |
| MSMetropolitan Steel I/steelco | Sinking Spring | PA | — | ◇ UNVERIFIED |
| MSMetro Steel | Spring Valley | CA | — | ◇ UNVERIFIED |
| MMMetso Minerals | Milwaukee | WI | — | ◇ UNVERIFIED |
| MBMetwood Building Solutions | Boones Mill | VA | — | ◇ UNVERIFIED |
| MCMexico City Iron Works | San Francisco | CA | — | ◇ UNVERIFIED |
| MCMeyers Construction INC | Madera | CA | — | ◇ UNVERIFIED |
 Meyer Utility Structures, LLC Plant No. 1663 | Hager City | WI | — | ◇ UNVERIFIED |
| MCMgk/homer City | Homer City | PA | — | ◇ UNVERIFIED |
| MMMHS Management LLC | Pleasant Grove | UT | — | ◇ UNVERIFIED |
| MEMichael E Taylor | Oregon City | OR | — | ◇ UNVERIFIED |
| MZMichal Zieba | Brooklyn | NY | — | ◇ UNVERIFIED |
| MIMichelman-cancelliere Iron Works, INC. | Bath | PA | — | ◇ UNVERIFIED |
| MSMichelman Steel | Allentown | PA | — | ◇ UNVERIFIED |
| MPMicrotek Pattern Inc | Decatur | IL | — | ◇ UNVERIFIED |
| MAMid America Steel Inc-fargo | Fargo | ND | — | ◇ UNVERIFIED |
| MSMid-america Steel Products, INC. | Corning | AR | — | ◇ UNVERIFIED |
| MSMid-atlantic Steel, LLC | New Castle | DE | — | ◇ UNVERIFIED |
| MFMidland Fabricators & Process Systems LLC | Metairie | LA | — | ◇ UNVERIFIED |
| MIMid-park INC - Mid-park Highway | Leitchfield | KY | — | ◇ UNVERIFIED |
| MIMid-park INC - Mid-park Highway | Leitchfield | KY | — | ◇ UNVERIFIED |
| MMMid-south Maintenance, INC. | Memphis | TN | — | ◇ UNVERIFIED |
| MSMid South Steel INC | Pelham | AL | — | ◇ UNVERIFIED |
| MMMid-state Machineand Fabricating CORP. | Lakeland | FL | — | ◇ UNVERIFIED |
| MMMidstate Manufacturing & Marketing, INC. | Oklahoma City | OK | — | ◇ UNVERIFIED |
| MFMidstream Fuel Service LLC (harbor Island) | Aransas Pass | TX | — | ◇ UNVERIFIED |
| MVMid Valley Metal Works, Inc. | Salem | OR | — | ◇ UNVERIFIED |
| MVMid Valley Sheet Metal INC. | La Feria | TX | — | ◇ UNVERIFIED |
| MMMidwest Machine Products INC | Golden | CO | — | ◇ UNVERIFIED |
| MMMidwest Manufacturing Corporation | Omaha | NE | — | ◇ UNVERIFIED |
| MRMidwest Racking Manufacturing, INC. | Madison | IL | — | ◇ UNVERIFIED |
| MSMidwest Steel and Rebar LLC | Seymour | MO | — | ◇ UNVERIFIED |
| MSMidwest Steel Fabricators CO INC | Wichita | KS | — | ◇ UNVERIFIED |
| MOMike Owen Fabrication | Bakersfield | CA | — | ◇ UNVERIFIED |
| MOMike Owens Fabrication, INC. | Lancaster | CA | — | ◇ UNVERIFIED |
| MMMikes Metal Works INC | Jamul | CA | — | ◇ UNVERIFIED |
| MJMikey Johns Outdoor, L.L.C. | Lake City | IA | — | ◇ UNVERIFIED |
| MFMillenium Facility Services INC | Tallapoosa | GA | — | ◇ UNVERIFIED |
| MFMillers Fab & Weld Corporation | Riverside | CA | — | ◇ UNVERIFIED |
| MEMillmark Enterprises, INC. | Elkhart | IN | — | ◇ UNVERIFIED |
 Mills Manufacturing INC | Earlville | IA | — | ◇ UNVERIFIED |
| MMMill-Tech Manufacturing LLC | New London | WI | — | ◇ UNVERIFIED |
| MVMillvale Vault | Glenshaw | PA | — | ◇ UNVERIFIED |
| MMMil Mar Centruy CORP. | Dayton | OH | — | ◇ UNVERIFIED |
 Minestone Construction | Hillsborough | NJ | — | ◇ UNVERIFIED |
| MEMingle & Elrod INC Dba Performance Steel INC | Murfreesboro | TN | — | ◇ UNVERIFIED |
