| OMF | | Personal Credit Institutions | 1584207 |
| OMH | | Real Estate Agents & Managers (For Others) | 1944902 |
| OMI | | Wholesale-Medical, Dental & Hospital Equipment & Supplies | 75252 |
| OMQS | | Services-Computer Integrated Systems Design | 278165 |
| OMSE | | Oil & Gas Field Machinery & Equipment | 2012219 |
| OMTK | | Motor Vehicle Parts & Accessories | 1404804 |
| ON | | Semiconductors & Related Devices | 1097864 |
| ONAR | | Construction - Special Trade Contractors | 1682265 |
| ONB | | National Commercial Banks | 707179 |
| ONC | | Pharmaceutical Preparations | 1651308 |
| ONCH | | Blank Checks | 2054272 |
| ONCO | | Pharmaceutical Preparations | 1782107 |
| ONCY | | Pharmaceutical Preparations | 1129928 |
| ONDS | | Radio & Tv Broadcasting & Communications Equipment | 1646188 |
| ONEG | | General Bldg Contractors - Residential Bldgs | 2030834 |
| ONEI | | Services-Computer Processing & Data Preparation | 1388295 |
| ONEW | | Retail-Auto & Home Supply Stores | 1772921 |
| ONFO | | Services-Computer Processing & Data Preparation | 1825452 |
| ONIT | | Mortgage Bankers & Loan Correspondents | 873860 |
| ONL | | Real Estate Investment Trusts | 1873923 |
| ONMD | | Services-Commercial Physical & Biological Research | 1849380 |
| ONON | | Rubber & Plastics Footwear | 1858985 |
| ONSS | | Deep Sea Foreign Transportation of Freight | 1279740 |
| ONTF | | Services-Prepackaged Software | 1110611 |
| ONTO | | Measuring & Controlling Devices, NEC | 704532 |
| ONWRY | | - | 2059986 |
| OOMA | | Services-Computer Processing & Data Preparation | 1327688 |
| OPAD | | Real Estate Agents & Managers (For Others) | 1825024 |
| OPAL | | Gas & Other Services Combined | 1842279 |
| OPBK | | State Commercial Banks | 1722010 |
| OPCH | | Services-Home Health Care Services | 1014739 |
| OPEN | | Real Estate Agents & Managers (For Others) | 1801169 |
| OPFI | | Finance Services | 1818502 |
| OPGN | | Services-Medical Laboratories | 1293818 |
| OPHC | | National Commercial Banks | 1288855 |
| OPITQ | | Real Estate | 1456772 |
| OPK | | Pharmaceutical Preparations | 944809 |
| OPP | | - | 1678130 |
| OPRA | | Services-Prepackaged Software | 1737450 |
| OPRT | | Finance Services | 1538716 |
| OPRX | | Services-Business Services, NEC | 1448431 |
| OPTH | | Pharmaceutical Preparations | 2027329 |
| OPTT | | Electric Services | 1378140 |
| OPTU | | Cable & Other Pay Television Services | 1702780 |
| OPTX | | Optical Instruments & Lenses | 1866816 |
| OPXS | | Optical Instruments & Lenses | 1397016 |
| OPY | | Security Brokers, Dealers & Flotation Companies | 791963 |
| OR | | Gold and Silver Ores | 1627272 |
| ORA | | Electric Services | 1296445 |
| ORBS | | Short-Term Business Credit Institutions | 1892492 |
