| HDHunter Douglas Architectural Products INC. | Norcross | GA | — | ◇ UNVERIFIED |
| HMHunter Metal | Tahoe Vista | CA | — | ◇ UNVERIFIED |
| HTHyperloop Technologies, INC | Moapa | NV | — | ◇ UNVERIFIED |
| HTHy-tech Truck & Trailer Mfg LLC | Fort Morgan | CO | — | ◇ UNVERIFIED |
| IEIan Eddy Blacksmith | Saxtons River | VT | — | ◇ UNVERIFIED |
| IAI & A Properties, LLC | Midland | NC | — | ◇ UNVERIFIED |
| IGIbarra Group LLC | Chicago | IL | — | ◇ UNVERIFIED |
| IFICON Fabrications LLC | Goose Creek | SC | — | ◇ UNVERIFIED |
| IMIcon Metal Works INC Dba Icon Structures | Fontana | CA | — | ◇ UNVERIFIED |
| ISIcon Steel, LLC | Georgetown | TX | — | ◇ UNVERIFIED |
| IIIda Installations, INC. | Southington | CT | — | ◇ UNVERIFIED |
| IPIdeal Portable Buildings & Carports* | West Monroe | LA | — | ◇ UNVERIFIED |
| IPIdeal Products of America | Malvern | PA | — | ◇ UNVERIFIED |
| IMIgnacio Martinez Dba Sunset and Company | Apple Valley | CA | — | ◇ UNVERIFIED |
| IOIhp Operations, LLC | Santa Ana | CA | — | ◇ UNVERIFIED |
| ITIllinois Tool Works INC | Bakersfield | CA | — | ◇ UNVERIFIED |
| IFImperial Fabricating INC. (closed) | Madison | TN | — | ◇ UNVERIFIED |
| IRImperial Rotary Dies | Santa Fe Spgs | CA | — | ◇ UNVERIFIED |
| ISImperial Steel Craft INC | Hillsboro | OR | — | ◇ UNVERIFIED |
| IIIncom, INC. | Kailua Kona | HI | — | ◇ UNVERIFIED |
| ISIndependent Steel LLC | Manassas | VA | — | ◇ UNVERIFIED |
| ISIndiana Steel and Engineering Corporation | Bedford | IN | — | ◇ UNVERIFIED |
| ICIndustrial Contractors | Evansville | IN | — | ◇ UNVERIFIED |
| IDIndustrial Design Fabrication & Installation, INC. | Sioux City | IA | — | ◇ UNVERIFIED |
| IFIndustrial Fabrication Services INC | Lake Crystal | MN | — | ◇ UNVERIFIED |
| IFIndustrial Fabrication Services INC | Lake Crystal | MN | — | ◇ UNVERIFIED |
| IFIndustrial Fabricators | Gastonia | NC | — | ◇ UNVERIFIED |
| IFIndustrial Fabricators INC. | Gastonia | NC | — | ◇ UNVERIFIED |
| IFIndustrial Fabricators, INC - Vc Plant | Gastonia | NC | — | ◇ UNVERIFIED |
| IFIndustrial Fabricators of Virgina INC | Verona | VA | — | ◇ UNVERIFIED |
| IFIndustrial Fabricators of Virginia INC | Fishersville | VA | — | ◇ UNVERIFIED |
| IMIndustrial Machine & Mfg CO | South El Monte | CA | — | ◇ UNVERIFIED |
| IMIndustrial Manufacturing and Installations, Inc | Sedalia | CO | — | ◇ UNVERIFIED |
| IPIndustrial Plating & Machine, INC. | Bluefield | WV | — | ◇ UNVERIFIED |
| IPIndustrial Precision Coatings INC | Randolph | MA | — | ◇ UNVERIFIED |
| ISIndustrial Sheetmetal & Fabricators, INC. | Vidor | TX | — | ◇ UNVERIFIED |
| ISIndustrial Steel Construction Incorporated | Gary | IN | — | ◇ UNVERIFIED |
| ISIndustrial Steel Fabrication, Incorporated | Hazelwood | MO | — | ◇ UNVERIFIED |
| ISIndustrial Steel Fabricators, INC. | Jacksonville | FL | — | ◇ UNVERIFIED |
 Industrial Tool & Die Co., INC. | Harlingen | TX | — | ◇ UNVERIFIED |
| ITIndustrial Toolz INC | Kenosha | WI | — | ◇ UNVERIFIED |
| ILInesh LLC | Phoenix | AZ | — | ◇ UNVERIFIED |
| ICInfra-metals CO. | Marseilles | IL | — | ◇ UNVERIFIED |
| ILInnofab LLC | Milwaukee | WI | — | ◇ UNVERIFIED |
| IIInnovations in Iron INC | Eugene | OR | — | ◇ UNVERIFIED |
| IAInnovative Architectural Solutions INC | Ontario | CA | — | ◇ UNVERIFIED |
| IIInnovative Industrial | Brownsville | TX | — | ◇ UNVERIFIED |
| IIInnovative Industrial Fabricators LLC | Keithville | LA | — | ◇ UNVERIFIED |
| IMInnovative Metal Design INC | Troutdale | OR | — | ◇ UNVERIFIED |
| IMInnovative Metal Solutions | Mount Holly | NJ | — | ◇ UNVERIFIED |
