| Abbreviation | Definition |
|---|---|
| ISIG | Insignia Systems, Inc. |
| ISIL | Intersil Holding Company |
| ISIP | Isis Pharmaceuticals, Inc. |
| ISIS | Independence Square Income Securities |
| ISKO | Isco, Inc. |
| ISLD | Digital Island, Inc. |
| ISLD | Digital Island, Incorporated |
| ISLE | Isle of Capri Casino |
| ISMR | Internet Stock Market Resources |
| ISMT | International Smart Sourcing, Inc. |
| ISMTW | International Smart Sourcing, Inc. Warrants |
| ISNS | Image Sensing Systems, Inc. |
| ISOL | Image Software, Inc. |
| ISON | Isonics Corporation |
| ISPD | Interspeed |
| ISPPE | Insulated Shipping Containers |
| ISRL | Isramco, Inc. |
| ISSI | Integrated Silicon Solutions, Inc. |
| ISSS | Integrated Spatial Information Systems |
| ISSX | I S S Group, Inc. |