| Ohno Construction Company WA | Construction | 0 | — | F |
| Ohno-Touchdown JV WA | Construction | 0 | — | A |
| Ohsmtede Ltd TX | Other Services | 0 | — | A |
| OHT IV, LLC OK | Accommodation & Food Services | 0 | — | A |
| Ohta Press U.S., Inc. OH | Manufacturing | 0 | — | F |
| OI System Holdings, LLC VA | Transportation & Warehousing | 0 | — | A |
| OIA Global KY | — | 0 | — | — |
| OIA Global NV | — | 0 | — | — |
| OIA Global Logistics CA | Transportation & Warehousing | 0 | — | C |
| OIA Global Logistics FL | Transportation & Warehousing | 0 | — | A |
| OIA Global Logistics GA | Transportation & Warehousing | 0 | — | A |
| OIA Global Logistics IL | Transportation & Warehousing | 0 | — | B |
| OIA Global Logistics KY | Transportation & Warehousing | 0 | — | A |
| OIA Global Logistics NJ | Transportation & Warehousing | 0 | — | A |
| OIA Global Logistics NV | Transportation & Warehousing | 0 | — | A |
| OIA Global Logistics NY | Transportation & Warehousing | 0 | — | A |
| OIA Global Logistics OH | Transportation & Warehousing | 0 | — | A |
| OIA Global Logistics OR | Transportation & Warehousing | 0 | — | A |
| OIA Global Logistics TX | Transportation & Warehousing | 0 | — | A |
| OIAE SYSTEMS LLC. FL | Professional & Technical Services | 2 | $88,750 | — |
| OIK Industries MI | Manufacturing | 0 | — | F |
| Oikos Roofing and Siding Inc VA | Construction | 0 | — | A |
| Oil Capital Electric, LLC OK | Construction | 0 | — | A |
| Oil Center Research LLC LA | Wholesale Trade | 0 | — | A |
| Oil City Iron Works Inc. TX | Manufacturing | 0 | — | F |
| Oil Creek Plastics PA | Manufacturing | 0 | — | F |
| Oil Equipment Co., Inc. WI | Construction | 0 | — | C |
| OIL PATCH GROUP, INC. TX | Real Estate | 0 | — | A |
| Oil Search (Alaska) LLC AK | Mining & Extraction | 3 | $231,333 | — |
| Oil Spill Response Limited FL | Other Services | 0 | — | A |
| Oil Spill Response USA Inc FL | Other Services | 0 | — | A |
| Oil States OK | Manufacturing | 0 | — | D |
| OIL STATES INDUSTRIES, INC. TX | Manufacturing | 0 | — | F |
| OIL TOOL SOLUTIONS LLC TX | Manufacturing | 0 | — | A |
| Oil-Rite Corporation WI | Manufacturing | 0 | — | F |
| Oilars Ag Services CA | Agriculture & Forestry | 0 | — | A |
| Oiles America Corporation NC | Manufacturing | 0 | — | F |
| OILFIELD EQUIPMENT MANUFACTURING Inc OK | Manufacturing | 0 | — | A |
| Oilfield Industrial Supply of Louisiana, Inc LA | Retail Trade | 0 | — | A |
| Oilfield Instrumentation LA | Mining & Extraction | 0 | — | A |
| Oilfield Service Professionals LLC LA | Mining & Extraction | 0 | — | A |
| Oilfield Trucking Solutions, a subsidiary of Seventy Seven Energy, Inc. TX | — | 0 | — | — |
| Oilmen's Equipment Corporation SC | Manufacturing | 0 | — | F |
| OilQuick Americas, LLC WI | Manufacturing | 0 | — | A |
| OILSTOP LLC CA | Other Services | 0 | — | F |
| Oishii NJ | Agriculture & Forestry | 0 | — | F |
| Oishii Farm Corporation CA | — | 0 | — | — |
| Oishii Farm Corporation NJ | Agriculture & Forestry | 1 | $92,978 | A |
| OJ Insulation, LP CA | Construction | 0 | — | F |
| OJA DEVELOPMENT COMPANY LTD. FL | Accommodation & Food Services | 0 | — | A |
