| BIBycap INC | Chicago, IL | Computer and Electronic Product Manufacturing334416 | 20–99 | ● ACTIVE |
| CBCarl Buddig & Company | Montgomery, IL | Food Manufacturing311612 | — | ● ACTIVE |
Carstens, Incorporated | Harwood Heights, IL | Miscellaneous Manufacturing339112 | — | ● ACTIVE |
Catalytic Products International INC | Lake Zurich, IL | Fabricated Metal Product Manufacturing332999 | — | ● ACTIVE |
Cat-i Manufacturing INC. | South Elgin, IL | Nonmetallic Mineral Product Manufacturing327212 | — | ● ACTIVE |
C & C Power INC | Carol Stream, IL | Electrical Equipment, Appliance & Component Manufacturing335311 | — | ● ACTIVE |
C E Niehoff & CO | Evanston, IL | Transportation Equipment Manufacturing336320 | — | ● ACTIVE |
Central Wire, INC. | Union, IL | Primary Metal Manufacturing331222 | 20–99 | ● ACTIVE |
Century Metal Spinning CO | Bensenville, IL | Fabricated Metal Product Manufacturing332119 | 20–99 | ● ACTIVE |
| CMCherry Meat Packers, INC | Chicago, IL | Food Manufacturing311611 | — | ● ACTIVE |
Chicago Anodizing CO | Chicago, IL | Fabricated Metal Product Manufacturing332813 | — | ● ACTIVE |
Chicago Booth Manufacturing INC | Chicago, IL | Furniture and Related Product Manufacturing337127 | 20–99 | ● ACTIVE |
| CMChicago Metal Rolled Products Company | Chicago, IL | Primary Metal Manufacturing331221 | 20–99 | ● ACTIVE |
| CMChucking Machine Products, INC. | Franklin Park, IL | Fabricated Metal Product Manufacturing332710 | 20–99 | ● ACTIVE |
Classic Products INC | Mchenry, IL | Fabricated Metal Product Manufacturing332613 | — | ● ACTIVE |
Clear Armor, LLC | Grayslake, IL | Plastics and Rubber Products Manufacturing326130 | 20–99 | ● ACTIVE |
Coapt, LLC | Chicago, IL | Computer and Electronic Product Manufacturing334510 | — | ● ACTIVE |
| CICoilcraft INC | Cary, IL | Computer and Electronic Product Manufacturing334416 | 100–499 | ● ACTIVE |
Color Communications, LLC | Chicago, IL | Paper Manufacturing322220 | — | ● ACTIVE |
Columbia Metal Spinning CO | Chicago, IL | Fabricated Metal Product Manufacturing332119 | 20–99 | ● ACTIVE |
Combined Metals Company, LLC | Elgin, IL | Primary Metal Manufacturing331221 | 20–99 | ● ACTIVE |
Combined Metals Company LLC - Hampshire | Hampshire, IL | Primary Metal Manufacturing331221 | 100–499 | ● ACTIVE |
Concept Industries INC | Elk Grove Village, IL | Fabricated Metal Product Manufacturing332322 | 1–19 | ● ACTIVE |
Contemporary Control Systems INC | Downers Grove, IL | Computer and Electronic Product Manufacturing334119 | — | ● ACTIVE |
Continental Web Press INC | Itasca, IL | Printing and Related Support Activities323110 | — | ● ACTIVE |
Control Systems INC | Lake Zurich, IL | Computer and Electronic Product Manufacturing334519 | — | ● ACTIVE |
Cory Laboratories INC | Alsip, IL | Miscellaneous Manufacturing339114 | — | ● ACTIVE |
Craftsman Tool & Mold CO. | Aurora, IL | Machinery Manufacturing333515 | 20–99 | ● ACTIVE |
Cts Advanced Materials, LLC | Lisle, IL | Computer and Electronic Product Manufacturing334419 | — | ● ACTIVE |
Cts Corporation | Lisle, IL | Computer and Electronic Product Manufacturing334419 | — | ● ACTIVE |
| CACustom Aluminum Products | Genoa, IL | Primary Metal Manufacturing331318 | 100–499 | ● ACTIVE |
| CACustom Aluminum Products INC | South Elgin, IL | Primary Metal Manufacturing331316 | 100–499 | ● ACTIVE |
| CCCynamic Chemical Company | Batavia, IL | Chemical Manufacturing325611 | 20–99 | ● ACTIVE |
Damron CORP | Chicago, IL | Food Manufacturing311920 | — | ● ACTIVE |
Data Weighing Systems INC | Wood Dale, IL | Machinery Manufacturing333997 | 1–19 | ● ACTIVE |
Daubert Chemical Company, INC. | Chicago, IL | Petroleum and Coal Products Manufacturing324191 | — | ● ACTIVE |
Deep Coat Industries LLC | Sugar Grove, IL | Fabricated Metal Product Manufacturing332812 | 20–99 | ● ACTIVE |
Defense Security Arms INC | Lake Barrington, IL | Fabricated Metal Product Manufacturing332994 | 20–99 | ● ACTIVE |
Del Medical, INC | Bloomingdale, IL | Computer and Electronic Product Manufacturing334517 | — | ● ACTIVE |
Dentalez Alabama, INC. | Chicago, IL | Machinery Manufacturing333248 | — | ● ACTIVE |
| DSDesigned Stairs INC | Sandwich, IL | Wood Product Manufacturing321918 | 20–99 | ● ACTIVE |
Dexter Magnetic Technologies, INC. | Elk Grove Village, IL | Fabricated Metal Product Manufacturing332999 | 100–499 | ● ACTIVE |
Diamond Envelope CORP | Aurora, IL | Paper Manufacturing322230 | 20–99 | ● ACTIVE |
Dickey Opco, LLC | Saint Charles, IL | Miscellaneous Manufacturing339991 | — | ● ACTIVE |
Dimension Inx CORP. | Chicago, IL | Miscellaneous Manufacturing339113 | — | ● ACTIVE |
Distinctive Dental Studio. Limited | Naperville, IL | Miscellaneous Manufacturing339116 | 20–99 | ● ACTIVE |
| DADjw Assembly INC | Arlington Heights, IL | Fabricated Metal Product Manufacturing332710 | — | ● ACTIVE |
| DADomino Amjet INC | Gurnee, IL | Chemical Manufacturing325910 | 100–499 | ● ACTIVE |
Drumbeaters of America INC | Elburn, IL | Machinery Manufacturing333298 | — | ● ACTIVE |
Dynamic Manufacturing INC | Hillside, IL | Paper Manufacturing322211 | — | ● ACTIVE |