| Abbreviation | Definition |
|---|---|
| OFG | Oriental Financial Group, Inc. |
| OFGPA | Oriental Financial Group, Inc. Preferred A |
| OG | Ogden Corporation |
| OGE | O G E Energy Corporation |
| OGEN | Oragenics, Inc. |
| OGEP | O G E Energy Corporation Capital Trust I |
| OH | Oakwood Homes Corporation |
| OHI | Omega Healthcare Investments, Inc. |
| OHIPA | Omega Healthcare Investments, Inc. Preferred A |
| OHIPB | Omega Healthcare Investments, Inc. Preferred B |
| OHP | Oxford Health Plans, Inc. |
| OI | Owens Illinois, Inc. |
| OIA | Morgan Stanley Dean Witter |
| OIB | Morgan Stanley Dean Witter |
| OIC | Morgan Stanley Dean Witter |
| OII | Oceaneering International, Inc. |
| OII | Oceaneering International, Incorporated |
| OIL | Triton Energy, LTD. |
| OIS | Oil States International |
| OJA | Ohio Power Company Class A |