| Abbreviation | Definition |
|---|---|
| ODWA | Odwalla, Inc. |
| OFCP | Ottawa Financial Corporation |
| OFED | Oconee Federal Financial Corp. |
| OFFI | Ood Fashion Foods, Inc. |
| OFFI | Ood Fashion Foods, Incorporated (de-listed) |
| OFFI | Ood Fashion Foods, Incorporated (de-listed) |
| OFIS | U S Office Products Company |
| OFIX | Orthofix International |
| OFLD | Officeland, Inc. |
| OFLDU | Officeland, Inc. |
| OFLF | Officeland, Inc. |
| OGAM | Online Gaming Systems |
| OGEEL | Oklahoma Gas & Electric Company |
| OGEEO | Oklahoma Gas & Electric Company |
| OGGI | Old Guard Group, Inc. |
| OGLE | Oglebay Norton Company |
| OGNC | Organic, Inc. |
| OGPS | Omicron Technologies, Inc. |
| OHIPM | Ohio Power Company Class M |
| OHIPM | Ohio Power Company Class M (de-listed) |