| Abbreviation | Definition |
|---|---|
| PREO | Precision Optics, Incorporated (de-listed) |
| PREV | Preventco, Inc. |
| PREZ | President Casinos, Inc. |
| PRFI | Performance Industries, Inc. |
| PRFN | Prism Financial Corporation |
| PRFS | Pennrock Financial Services Corporation |
| PRFT | Perficient, Inc. |
| PRGN | Peregrine Systems, Inc. |
| PRGO | Perrigo Company |
| PRGS | Progress Software Corporation |
| PRGX | Profit Recovery Group International |
| PRGY | Prodigy Communications Company |
| PRHC | Province Healthcare Company |
| PRIA | P R I Automation, Inc. |
| PRIB | Private Brands, Inc. |
| PRIME | PrimeHoldings.Com, Inc. |
| PRIT | Predict It, Inc. |
| PRIX | Processing Research, Inc. |
| PRKR | ParkerVision, Inc. |
| PRLN | Paracelsian, Inc. |