| IOImsamet of Arizona INC | Goodyear | AZ | Primary Metal Manufacturing331314 | 20-99 | ◐ LIKELY ACTIVE |
| IDInland Die Casting INC | Wheeling | IL | Primary Metal Manufacturing331521 | 100-499 | ◐ LIKELY ACTIVE |
| IPIntat Precision INC | Rushville | IN | Nonmetallic Mineral Product Manufacturing327213 | 100-499 | ◐ LIKELY ACTIVE |
| ICInternational Casting CORP | New Baltimore | MI | Primary Metal Manufacturing331511 | 1-19 | ◐ LIKELY ACTIVE |
| IEInternational Extrusion CORP Texas | Waxahachie | TX | Primary Metal Manufacturing331316 | 100-499 | ◐ LIKELY ACTIVE |
| ICInvest Cast INC | Minneapolis | MN | Primary Metal Manufacturing331512 | 20-99 | ◐ LIKELY ACTIVE |
| ISIowa Steel & Wire CO INC | Centerville | IA | Primary Metal Manufacturing331222 | 20-99 | ◐ LIKELY ACTIVE |
| JDJohn Deere Waterloo Works Drivetrain Operations & Foundry | Waterloo | IA | Primary Metal Manufacturing331511 | 500+ | ◐ LIKELY ACTIVE |
| JAJordan Aluminum Company, LLC | Memphis | TN | Primary Metal Manufacturing331316 | 100-499 | ◐ LIKELY ACTIVE |
| KAKaiser Aluminum | Heath | OH | Primary Metal Manufacturing331312 | 100-499 | ◐ LIKELY ACTIVE |
Kaiser Aluminum Fabricated Products LLC | Kalamazoo | MI | Primary Metal Manufacturing331312 | 100-499 | ◐ LIKELY ACTIVE |
| KIKamtek INC | Birmingham | AL | Primary Metal Manufacturing331523 | 500+ | ◐ LIKELY ACTIVE |
| KVKennedy Valve Div Mc Wane INC | Elmira | NY | Primary Metal Manufacturing331511 | 100-499 | ◐ LIKELY ACTIVE |
| KFKent Foundry CO. | Greenville | MI | Primary Metal Manufacturing331511 | 20-99 | ◐ LIKELY ACTIVE |
| KCKentucky Chrome Works LLC | Horse Cave | KY | Primary Metal Manufacturing331529 | — | ◐ LIKELY ACTIVE |
| KSKeokuk Steel Castings a Matrix Metals CO LLC | Keokuk | IA | Primary Metal Manufacturing331222 | 100-499 | ◐ LIKELY ACTIVE |
| KKKowa Kentucky , INC. | Corbin | KY | Primary Metal Manufacturing331491 | 1-19 | ◐ LIKELY ACTIVE |
| KCKsm Castings Usa, INC. | Shelby | NC | Primary Metal Manufacturing331521 | 100-499 | ◐ LIKELY ACTIVE |
| KAKt Acquisition Llc, Dba Komtek Forge | Worcester | MA | Primary Metal Manufacturing331512 | 20-99 | ◐ LIKELY ACTIVE |
| LRLake Region Medical, INC. | Salem | VA | Primary Metal Manufacturing331491 | 500+ | ◐ LIKELY ACTIVE |
| LBLee Brass Company | Anniston | AL | Primary Metal Manufacturing331523 | — | ◐ LIKELY ACTIVE |
| LPLinn Products INC | Charlotte | MI | Primary Metal Manufacturing331312 | 100-499 | ◐ LIKELY ACTIVE |
| LMLucas Milhaupt INC | Warwick | RI | Primary Metal Manufacturing331420 | 100-499 | ◐ LIKELY ACTIVE |
| LILufkin Industries INC | Lufkin | TX | Primary Metal Manufacturing331511 | 20-99 | ◐ LIKELY ACTIVE |
| MCMadison-kipp Corporation | Richmond | IN | Primary Metal Manufacturing331523 | 20-99 | ◐ LIKELY ACTIVE |
| MMMagnolia Metal CORP | Auburn | NE | Primary Metal Manufacturing331523 | 20-99 | ◐ LIKELY ACTIVE |
| MMMagnolia Metal & Plastic Products, INC | Vicksburg | MS | Plastics and Rubber Products Manufacturing326199 | 1-19 | ◐ LIKELY ACTIVE |
| MBMahle Behr Mt Sterling INC | Mount Sterling | OH | Primary Metal Manufacturing331318 | 100-499 | ◐ LIKELY ACTIVE |
| MFMahoney Foundries | Kendallville | IN | Primary Metal Manufacturing331524 | 100-499 | ◐ LIKELY ACTIVE |
| MGManitowoc Grey Iron Foundry INC | Manitowoc | WI | Primary Metal Manufacturing331511 | 1-19 | ◐ LIKELY ACTIVE |
| MUMarmon Utility LLC | Milford | NH | Primary Metal Manufacturing331318 | 100-499 | ◐ LIKELY ACTIVE |
| MSMatalco Shelbyville LLC | Shelbyville | KY | Primary Metal Manufacturing331314 | 100-499 | ◐ LIKELY ACTIVE |
| MBMaterion Brewster LLC | Brewster | NY | Primary Metal Manufacturing331491 | 20-99 | ◐ LIKELY ACTIVE |
| MBMaterion Brush INC | Lorain | OH | Primary Metal Manufacturing331314 | 20-99 | ◐ LIKELY ACTIVE |
Matthews International Corporation | Searcy | AR | Primary Metal Manufacturing331522 | 100-499 | ◐ LIKELY ACTIVE |
| MTMaverick Tube | Conroe | TX | Primary Metal Manufacturing331210 | 100-499 | ◐ LIKELY ACTIVE |
| MBMeskan Brass Foundry | Chicago | IL | Primary Metal Manufacturing331524 | 20-99 | ◐ LIKELY ACTIVE |
| MRMetallix Refining INC. | Greenville | NC | Primary Metal Manufacturing331314 | 20-99 | ◐ LIKELY ACTIVE |
| MIMetaltek Intl - Wisconsin Investcast | Watertown | WI | Primary Metal Manufacturing331510 | 100-499 | ◐ LIKELY ACTIVE |
| MIMetco Ind | Saint Marys | PA | Primary Metal Manufacturing331110 | 100-499 | ◐ LIKELY ACTIVE |
| MWMichigan Wheel CORP | Grand Rapids | MI | Primary Metal Manufacturing331525 | 20-99 | ◐ LIKELY ACTIVE |
| MAMid American Steel and Wire CO - Mill | Madill | OK | Primary Metal Manufacturing331110 | 100-499 | ◐ LIKELY ACTIVE |
| MMMidland Manufacturing CO. | Fort Worth | TX | Primary Metal Manufacturing331525 | 20-99 | ◐ LIKELY ACTIVE |
Midwest Metal Products INC | Winona | MN | Primary Metal Manufacturing331511 | 20-99 | ◐ LIKELY ACTIVE |
| MPMills Products, INC. | Athens | TN | Primary Metal Manufacturing331221 | 100-499 | ◐ LIKELY ACTIVE |
| MCMnp CORP | Utica | MI | Primary Metal Manufacturing331222 | 100-499 | ◐ LIKELY ACTIVE |
| MMMonett Metals INC | Monett | MO | Primary Metal Manufacturing331513 | 20-99 | ◐ LIKELY ACTIVE |
| MPMontana Precision Products LLC | Butte | MT | Primary Metal Manufacturing331512 | 100-499 | ◐ LIKELY ACTIVE |
| MBMorrison Brothers Company | Dubuque | IA | Primary Metal Manufacturing331524 | 1-19 | ◐ LIKELY ACTIVE |
| MIMorton Industries LLC | Morton | IL | Primary Metal Manufacturing331210 | 100-499 | ◐ LIKELY ACTIVE |