| Abbreviation | Definition |
|---|---|
| STS | Secs.scotland |
| STT | Straight |
| STT | Straight, P.L.C. (de-listed) |
| STT | Straight, P.L.C. (de-listed) |
| STTM | Strontium Plc |
| STV | Strathdon Inv |
| STVG | Stvg |
| STVW | Strathdon Wts |
| STY | Styles & Wood |
| STZ | Stavert Zig. |
| SUBX | Subex S |
| SUEL | Suzlon En. |
| SUH | Sutton Harbour |
| SUMM | Summit Corp |
| SUMM | Summit Corporation |
| SUN | Surgical Innov. |
| SUPA | Sunplus Gdr 144 |
| SUPD | Sunplus Gdr's' |
| SUS | S & U |
| SVCA | Servoca |