| Abbreviation | Definition |
|---|---|
| SIGYY | Signet Group, P. L. C. |
| SIII | S 3, Inc. |
| SILCF | Silicom LTD |
| SILI | Siliconix, Inc. |
| SILK | Silknet Software, Inc. |
| SILVZ | Sunshine Mining & REF Company |
| SILW | Silent Witness Enterprise |
| SIMA | Sonics & Materials, Inc. |
| SIMA | Sonics & Materials, Incorporated (de-listed) |
| SIMA | Sonics & Materials, Incorporated (de-listed) |
| SIMAW | Sonics & Materials, Inc. Warrants |
| SIMAW | Sonics & Materials, Incorporated Warrants (de-listed) |
| SIMAW | Sonics & Materials, Incorporated Warrants (de-listed) |
| SIMG | Silicon Image, Inc. |
| SIMG | Silicon Image, Incorporated (de-listed) |
| SIMG | Silicon Image, Incorporated (de-listed) |
| SIMN | Simon Transport Services, Inc. |
| SIMN | Simon Transport Services, Incorporated (de-listed) |
| SIMN | Simon Transport Services, Incorporated (de-listed) |
| SIMO | Silicon Motion Technology Corporation, American Depositary Receipts |