| CPCambridge Pattern Works | Cambridge | — | ◇ UNVERIFIED |
| CUCamfil Usa, INC. | Crystal Lake | — | ◇ UNVERIFIED |
| CICaterpillar INC. | Mapleton | — | ◇ UNVERIFIED |
| CSCentral Steel & Wire | University Park | — | ◇ UNVERIFIED |
| CCCentury Casting Corporation | Belleville | — | ◇ UNVERIFIED |
| CCCentury Castings Corporation | Swansea | — | ◇ UNVERIFIED |
| CSCharter Steel Trading | Chicago | — | ◇ UNVERIFIED |
| CHChicago Heights Brass Foundry, INC. | Chicago Heights | — | ◇ UNVERIFIED |
| CVChicago Vacuum Castings CORP | Chicago | — | ◇ UNVERIFIED |
| CWChicago White Metal | Bensenville | — | ◇ UNVERIFIED |
| CSCi Starnes Products CO | Edwardsville | — | ◇ UNVERIFIED |
| CSC&j Sales | Chatham | — | ◇ UNVERIFIED |
| CSClingan Steel, INC. | Des Plaines | — | ◇ UNVERIFIED |
| CFCmi Frank S Ryan Memorial | Des Plaines | — | ◇ UNVERIFIED |
| CSCobin Salvage Yard INC | Dowell | — | ◇ UNVERIFIED |
| CCColeman Cable INC | North Chicago | — | ◇ UNVERIFIED |
| CMCompeer Metals, INC. | Algonquin | — | ◇ UNVERIFIED |
| CMContinental Metals INC | Lasalle | — | ◇ UNVERIFIED |
| CCCopperweld Chicago Division | Chicago | — | ◇ UNVERIFIED |
| CMCosmos Manufacturing, INC. | South Chicago Heights | — | ◇ UNVERIFIED |
| CCCountry Cast Products INC | Galena | — | ◇ UNVERIFIED |
| CSCrane & Steel Inc.* | Addison | — | ◇ UNVERIFIED |
| CSCustom Steel Processing, INC. | Granite City | — | ◇ UNVERIFIED |
| CSCw Shumway & Sons | Batavia | — | ◇ UNVERIFIED |
| DCDeniston CO | Alsip | — | ◇ UNVERIFIED |
| DIDima Industries | Elk Grove Village | — | ◇ UNVERIFIED |
| DDDo-rite Die & Engineering Company | Chicago Heights | — | ◇ UNVERIFIED |
| DMDulin Metals CO | Joliet | — | ◇ UNVERIFIED |
| DIDurable Incorporated | Wheeling | — | ◇ UNVERIFIED |
| DPDurable Packaging International, INC. | Lincolnshire | — | ◇ UNVERIFIED |
| DIDuro-cast, INC. | Somonauk | — | ◇ UNVERIFIED |
| FIFlexmag Industries, INC. | Marengo | — | ◇ UNVERIFIED |
| FCFluxxor Corporation | North Aurora | — | ◇ UNVERIFIED |
| FNFrancis & Nygren Foundry CO | Chicago | — | ◇ UNVERIFIED |
| GCGalesburg Castings INC | Galesburg | — | ◇ UNVERIFIED |
| GWGeorge Wilson | Danville | — | ◇ UNVERIFIED |
| GMGfi Metal Treating INC | Rockford | — | ◇ UNVERIFIED |
| GBGlobal Brass and Copper LLC Dba Olin Brass | East Alton | — | ◇ UNVERIFIED |
| GBGlobal Brass and Copper LLC Dba Olin Brass | East Alton | — | ◇ UNVERIFIED |
| GIGrand Iron Work INC. | Chicago | — | ◇ UNVERIFIED |
| HFHandi Foil | Antioch | — | ◇ UNVERIFIED |
| HCHandi-foil CORP. | Naperville | — | ◇ UNVERIFIED |
 Handi Products, INC. Dba Handi-ramp, INC. | Libertyville | — | ◇ UNVERIFIED |
| HDHeick Die Casting CORP | Chicago | — | ◇ UNVERIFIED |
| HPHutchinson Products LLC | Alton | — | ◇ UNVERIFIED |
| IKIce Krackers, INC. | Springfield | — | ◇ UNVERIFIED |
| INIllinois Ni Cast, LLC | Champaign | — | ◇ UNVERIFIED |
| IWIllinois Weld & Machine, INC. | Hanna City | — | ◇ UNVERIFIED |
| IPIndustrial Properties of Palatine, LLC | Palatine | — | ◇ UNVERIFIED |
| JIJernberg Industries INC | Chicago | — | ◇ UNVERIFIED |
