| Abbreviation | Definition |
|---|---|
| URIX | Uranium Resources, Incorporated (de-listed) |
| URIX | Uranium Resources, Incorporated (de-listed) |
| URMD | Uromed Corporation |
| UROG | Urogen Corporation |
| UROP | Uroplasty, Inc. |
| UROP | Uroplasty, Incorporated (de-listed) |
| UROP | Uroplasty, Incorporated (de-listed) |
| URPL | United Reef, LTD. |
| URPP | Uranium Prospects PLC |
| URSI | United Road Services, Inc. |
| URSI | United Road Services, Incorporated (de-listed) |
| URSI | United Road Services, Incorporated (de-listed) |
| URTSA | U R T Industries, Inc. Class A |
| URTSA | URT Industries, Incorporated Class A (de-listed) |
| URTSA | URT Industries, Incorporated Class A (de-listed) |
| URTSB | U R T Industries, Inc. Class B |
| URTSB | URT Industries, Incorporated Class B (de-listed) |
| URTSB | URT Industries, Incorporated Class B (de-listed) |
| USAB | USABancshares.Com, Inc. |
| USAB | USABancshares.Com, Incorporated (de-listed) |