| Name | Price | Change |
|---|---|---|
| ACLI | American Commercial Lines Inc | + 3:35PM ET |
| ACLS | Axcelis Technologies, Inc. | + 3:36PM ET |
| ACMR | A.C. Moore Arts & Crafts, Inc. | + 3:34PM EDT |
| ACOM | Ancestry.com, Inc. | + 3:28PM EDT |
| ACOR | Acorda Therapeutics, Inc. | + 3:36PM EDT |
| Acorda Therapeutics, Inc. | 32.51 | - 0.73 |
| Acorn Energy, Inc. | 4.76 | + 0.19 |
| ACPW | Active Power, Inc. | + 3:25PM EDT |
| Actel Corporation | 14.80 | + 0.50 |
| ACTG | Acacia Research Corporation | + 3:36PM EDT |
| ACTI | ActivIdentity Corporation | + 3:34PM EDT |
| Actions Semiconductor Co., Ltd. | 2.15 | + 0.01 |
| Active Power, Inc. | 1.11 | - 0.04 |
| ActivIdentity Corporation | 2.00 | + 0.07 |
| ACTL | Actel Corporation | + 3:35PM EDT |
| ACTS | Actions Semiconductor Co., Ltd. | + 3:22PM EDT |
| ACTU | Actuate Corporation | + 3:36PM EDT |
| Actuate Corporation | 4.26 | + 0.01 |
| ACUR | Acura Pharmaceuticals, Inc. | + 3:35PM EDT |
| Acura Pharmaceuticals, Inc. | 2.49 | + 0.04 |
| Acxiom Corporation | 14.24 | + 0.37 |
| ACXM | Acxiom Corporation | + 3:36PM EDT |