| CMColonial Machine Company | Kent | OH | Machinery Manufacturing333511 | 20-99 | ◐ LIKELY ACTIVE |
| CSColonial Surface Solutions, INC. | Columbus Grove | OH | Fabricated Metal Product Manufacturing332812 | 20-99 | ◐ LIKELY ACTIVE |
Columbus Apparel Studio, LLC | Columbus | OH | Apparel Manufacturing315210 | — | ◐ LIKELY ACTIVE |
| CMCommercial Metal Forming | Youngstown | OH | Fabricated Metal Product Manufacturing332116 | 20-99 | ◐ LIKELY ACTIVE |
| CBConagra Brands | Archbold | OH | Food Manufacturing311412 | — | ◐ LIKELY ACTIVE |
| CMConnector Manufacturing CO | Hamilton | OH | Fabricated Metal Product Manufacturing332710 | 100-499 | ◐ LIKELY ACTIVE |
| CSContinental Structural Plastics (0388000002) | Carey | OH | Plastics and Rubber Products Manufacturing326199 | — | ◐ LIKELY ACTIVE |
| CFContour Forming INC | Newark | OH | Machinery Manufacturing333514 | 1-19 | ◐ LIKELY ACTIVE |
| CBCook Bonding & Manufacturing CO | Cleveland | OH | Fabricated Metal Product Manufacturing332312 | — | ◐ LIKELY ACTIVE |
| CFCooper Farms North Mill | Fort Recovery | OH | Food Manufacturing311119 | — | ◐ LIKELY ACTIVE |
| CSCooper Standard Industrial and Specialty Group | New Philadelphia | OH | Plastics and Rubber Products Manufacturing326299 | 100-499 | ◐ LIKELY ACTIVE |
| CQCornwell Quality Tools CO. | Mogadore | OH | Fabricated Metal Product Manufacturing332212 | 100-499 | ◐ LIKELY ACTIVE |
| CICramers Inc | Canton | OH | Fabricated Metal Product Manufacturing332322 | 20-99 | ◐ LIKELY ACTIVE |
| CBCrest Bending, INC. | New Washington | OH | Fabricated Metal Product Manufacturing332322 | 20-99 | ◐ LIKELY ACTIVE |
| CCCrown Cork & Seal (0448010466) | Toledo | OH | Fabricated Metal Product Manufacturing332812 | — | ◐ LIKELY ACTIVE |
| CPCrown Plastics 116 | Harrison | OH | Plastics and Rubber Products Manufacturing326113 | 20-99 | ◐ LIKELY ACTIVE |
| CICsp Innovations INC | Conneaut | OH | Chemical Manufacturing325991 | — | ◐ LIKELY ACTIVE |
| CWC & W Grinding INC | Cleveland | OH | Fabricated Metal Product Manufacturing332710 | 1-19 | ◐ LIKELY ACTIVE |
| COCw Ohio, INC. (0204020069) | Conneaut | OH | Wood Product Manufacturing321911 | — | ◐ LIKELY ACTIVE |
Dana White Machining & Welding INC | Nova | OH | Fabricated Metal Product Manufacturing332999 | 1-19 | ◐ LIKELY ACTIVE |
| DSDaNite Sign Co | Columbus | OH | Miscellaneous Manufacturing339950 | 20-99 | ◐ LIKELY ACTIVE |
| DPDansons Peebles, LLC | Peebles | OH | Wood Product Manufacturing321999 | 20-99 | ◐ LIKELY ACTIVE |
| DMDatco Manufacturing LLC (0250110856) | Boardman | OH | Primary Metal Manufacturing331316 | — | ◐ LIKELY ACTIVE |
Daubenmire's Printing Company, LLC | Middletown | OH | Printing and Related Support Activities323111 | 1-19 | ◐ LIKELY ACTIVE |
| DCDay-glo Color CORP | Twinsburg | OH | Chemical Manufacturing325130 | — | ◐ LIKELY ACTIVE |
| DCDay-glo Color CORP. (1318006552) | Cleveland | OH | Chemical Manufacturing325130 | — | ◐ LIKELY ACTIVE |
| DIDegussa Initiators INC | Elyria | OH | Chemical Manufacturing325199 | — | ◐ LIKELY ACTIVE |
| DNDe Nora Tech | Mentor | OH | Fabricated Metal Product Manufacturing332813 | 100-499 | ◐ LIKELY ACTIVE |
| DIDesignetics, Inc. | Holland | OH | Plastics and Rubber Products Manufacturing326199 | 20-99 | ◐ LIKELY ACTIVE |
| DCDetrex Corporation, Ashtabula Plant (0204010192) | Ashtabula | OH | Chemical Manufacturing325180 | — | ◐ LIKELY ACTIVE |
| DPDiamond Power International INC | Lancaster | OH | Fabricated Metal Product Manufacturing332410 | 100-499 | ◐ LIKELY ACTIVE |
| DPDiamond Products Tool Division | Elyria | OH | Fabricated Metal Product Manufacturing332213 | 100-499 | ◐ LIKELY ACTIVE |
| DMDimensional Metals Inc | Reynoldsburg | OH | Fabricated Metal Product Manufacturing332322 | 20-99 | ◐ LIKELY ACTIVE |
| DGDlubak Glass | Upper Sandusky | OH | Nonmetallic Mineral Product Manufacturing327215 | 20-99 | ◐ LIKELY ACTIVE |
| DDDOG Distilling Company | Lewis Center | OH | Beverage and Tobacco Product Manufacturing312140 | — | ◐ LIKELY ACTIVE |
| DCDorn Color, INC. | Cleveland | OH | Printing and Related Support Activities323110 | 20-99 | ◐ LIKELY ACTIVE |
Dory Power LLC | Euclid | OH | Electrical Equipment, Appliance & Component Manufacturing335312 | — | ◐ LIKELY ACTIVE |
| DSDove Stamping, LLC | Cleveland | OH | Transportation Equipment Manufacturing336370 | 20-99 | ◐ LIKELY ACTIVE |
Dow Chemical Company - Ironton, Ohio Branch | Ironton | OH | Chemical Manufacturing325211 | — | ◐ LIKELY ACTIVE |
| DEDowning Enterprises, Inc. | Copley | OH | Miscellaneous Manufacturing339950 | 20-99 | ◐ LIKELY ACTIVE |
| DMDrake Manufacturing LLC | Warren | OH | Machinery Manufacturing333517 | 20-99 | ◐ LIKELY ACTIVE |
| DMDRT MPS- Dayton | Dayton | OH | Machinery Manufacturing333514 | 100-499 | ◐ LIKELY ACTIVE |
| DCDubois Chemicals, INC | Sharonville | OH | Chemical Manufacturing325199 | — | ◐ LIKELY ACTIVE |
| DDuo-Corp. | North Lima | OH | Plastics and Rubber Products Manufacturing326199 | 20-99 | ◐ LIKELY ACTIVE |
| DEDupont Electronic Polymers | Dayton | OH | Chemical Manufacturing325110 | — | ◐ LIKELY ACTIVE |
| DDura-line | Elyria | OH | Plastics and Rubber Products Manufacturing326122 | 100-499 | ◐ LIKELY ACTIVE |
| DCDurez Corporation - Kenton Facility | Kenton | OH | Chemical Manufacturing325211 | — | ◐ LIKELY ACTIVE |
| DMDyco Manufacturing, INC | Montpelier | OH | Fabricated Metal Product Manufacturing332119 | 20-99 | ◐ LIKELY ACTIVE |
| DDDynamic Dies Holland | Holland | OH | Fabricated Metal Product Manufacturing332216 | 100-499 | ◐ LIKELY ACTIVE |
| EMEagle Machinery & Supply, Inc. | Sugarcreek | OH | Machinery Manufacturing333243 | 20-99 | ◐ LIKELY ACTIVE |