| MIMission Iron Works | Pacoima | CA | — | ◇ UNVERIFIED |
| MVMission Viejo Ornamental Iron,r Honarvar | Rancho Sta Margarita | CA | — | ◇ UNVERIFIED |
| MOMissouri Ornamental Iron Company, INC. | University City | MO | — | ◇ UNVERIFIED |
| MMM & M Contractors | Aberdeen | WA | — | ◇ UNVERIFIED |
 Modern Metal Solutions LLC | Hudson | NH | — | ◇ UNVERIFIED |
| MCMomomi CO LTD Dba Tru-form Metals | Livermore | CA | — | ◇ UNVERIFIED |
| MHMonarch Hardware Manufacturing | Shepherdsville | KY | — | ◇ UNVERIFIED |
| MMMonster Mud Pits INC. | Fort Stockton | TX | — | ◇ UNVERIFIED |
| MMMonster Mud Pits INC. | Mentone | TX | — | ◇ UNVERIFIED |
| MOMorgan's Outdoor Living INC. | Concord | CA | — | ◇ UNVERIFIED |
| MDMoz Designs INC | Livermore | CA | — | ◇ UNVERIFIED |
| MOMq Ornamental | Chula Vista | CA | — | ◇ UNVERIFIED |
| MOMueller Ornamental Iron Works, INC. | Elk Grove Village | IL | — | ◇ UNVERIFIED |
| MMMulti Metals Company, INC. | Greensburg | PA | — | ◇ UNVERIFIED |
| MMMunns Manufacturing INC. | Tremonton | UT | — | ◇ UNVERIFIED |
| MIMurray's Iron Works INC | Commerce | CA | — | ◇ UNVERIFIED |
| MMMusic's Metal Works, LLC. | Dayton | OH | — | ◇ UNVERIFIED |
| MM+v | El Paso | TX | — | ◇ UNVERIFIED |
| MIMwi INC | Minneapolis | MN | — | ◇ UNVERIFIED |
| MFMyers Fabrication INC | Eugene | OR | — | ◇ UNVERIFIED |
| NINext Innovations LTD | Walker | MN | — | ◇ UNVERIFIED |
| NINicks Iron Works, INC | Brooklyn | NY | — | ◇ UNVERIFIED |
| NMNick's Metal Fabricating & Sons, Inc. | Seneca | IL | — | ◇ UNVERIFIED |
| NBNor Bay Ironcraft | Petaluma | CA | — | ◇ UNVERIFIED |
| NCNortheast Construction Industries, INC. | Montgomery | NY | — | ◇ UNVERIFIED |
| NFNortheast Fence & Iron Works, INC. | Philadelphia | PA | — | ◇ UNVERIFIED |
| NCNorthern Containment LLC | Brainerd | MN | — | ◇ UNVERIFIED |
| NSNorth Star Safe LLC | Salt Lake City | UT | — | ◇ UNVERIFIED |
| NINova Industries INC | San Leandro | CA | — | ◇ UNVERIFIED |
| NFNowlin Fence INC | Anaheim | CA | — | ◇ UNVERIFIED |
| NGNucor Grating - Fisher & Ludlow INC. | Madison | MS | — | ◇ UNVERIFIED |
| NRNucor Rebar Fabrication Fontana | Fontana | CA | — | ◇ UNVERIFIED |
| NRNucor Rebar Fabrication Southwest INC | Lakeside | CA | — | ◇ UNVERIFIED |
| NINw Iron Works INC | Portland | OR | — | ◇ UNVERIFIED |
| OMO'Brien Metal Inc. | Chicago | IL | — | ◇ UNVERIFIED |
| OOObrien Ornamental Iron INC | Minneapolis | MN | — | ◇ UNVERIFIED |
| OCOctober CO Chemetal Division | Easthampton | MA | — | ◇ UNVERIFIED |
| OSOklahoma Stair Craft, INC. | Sapulpa | OK | — | ◇ UNVERIFIED |
| OSOld South Ironworks INC | Gray | TN | — | ◇ UNVERIFIED |
| OWOld World Iron | Gilroy | CA | — | ◇ UNVERIFIED |
| OOOliver's Ornamental Iron, LLC | Flora | MS | — | ◇ UNVERIFIED |
| OEOne Ez Post LLC | Kingsport | TN | — | ◇ UNVERIFIED |
| OFOnGuard Fence Systems, Ltd. | Moorestown | NJ | — | ◇ UNVERIFIED |
| ODOrnamental Design Inc | Tampa | FL | — | ◇ UNVERIFIED |
| OIOrnamental Iron Concept,bartolome Fluxa | Van Nuys | CA | — | ◇ UNVERIFIED |
| OIOrnamental Ironworks | Los Angeles | CA | — | ◇ UNVERIFIED |
| ODOscar Diaz Rivera | San Juan | PR | — | ◇ UNVERIFIED |
| OOOsuna Ornamental LLC | Miami | FL | — | ◇ UNVERIFIED |
| PMPacific Metal Works INC | Beaverton | OR | — | ◇ UNVERIFIED |
| PWPacific Waterjet Cutting INC | Chico | CA | — | ◇ UNVERIFIED |
