| SC 13G/A | 2011-02-14 | FMR LLC | WESCO INTERNATIONAL INC | 6,371,684 | 15.0% | EDGAR |
| SC 13G/A | 2011-02-14 | JANUS CAPITAL MANAGEMENT LLC | WESCO INTERNATIONAL INC | 2,915,265 | 6.9% | EDGAR |
| SC 13G/A | 2011-02-11 | PIONEER GLOBAL ASSET MANAGEMENT SPA | WESCO INTERNATIONAL INC | - | 4.6% | EDGAR |
| SC 13G/A | 2010-07-07 | SNOW CAPITAL MANAGEMENT LP | WESCO INTERNATIONAL INC | 2,020,124 | 4.8% | EDGAR |
| SC 13G/A | 2010-02-16 | FMR LLC | WESCO INTERNATIONAL INC | 5,512,635 | 13.0% | EDGAR |
| SC 13G | 2010-02-16 | JANUS CAPITAL MANAGEMENT LLC | WESCO INTERNATIONAL INC | 3,337,615 | 7.9% | EDGAR |
| SC 13G | 2010-02-16 | PIONEER GLOBAL ASSET MANAGEMENT SPA | WESCO INTERNATIONAL INC | - | 6.0% | EDGAR |
| SC 13G/A | 2010-02-12 | AXA FINANCIAL INC | WESCO INTERNATIONAL INC | 1,587,606 | 3.8% | EDGAR |
| SC 13G/A | 2010-01-12 | SNOW CAPITAL MANAGEMENT LP | WESCO INTERNATIONAL INC | 2,296,017 | 5.4% | EDGAR |
| SC 13G | 2009-09-10 | FMR LLC | WESCO INTERNATIONAL INC | 6,372,300 | 15.1% | EDGAR |
| SC 13G/A | 2009-03-06 | SNOW CAPITAL MANAGEMENT LP | WESCO INTERNATIONAL INC | 2,636,510 | 6.3% | EDGAR |
| SC 13G/A | 2009-02-17 | Ospraie Management, LLC | WESCO INTERNATIONAL INC | 0 | 0.0% | EDGAR |
| SC 13G/A | 2009-02-13 | PUTNAM LLC | WESCO INTERNATIONAL INC | 1,243,926 | 3.0% | EDGAR |
| SC 13G | 2009-02-13 | AXA FINANCIAL INC | WESCO INTERNATIONAL INC | 3,126,297 | 7.4% | EDGAR |
| SC 13G/A | 2009-02-10 | RS INVESTMENT MANAGEMENT CO LLC | WESCO INTERNATIONAL INC | - | 0.0% | EDGAR |
| SC 13G/A | 2009-02-04 | IRIDIAN ASSET MANAGEMENT LLC/CT | WESCO INTERNATIONAL INC | - | - | EDGAR |
| SC 13G/A | 2008-10-09 | SNOW CAPITAL MANAGEMENT LP | WESCO INTERNATIONAL INC | 2,084,060 | 4.9% | EDGAR |
| SC 13G | 2008-05-07 | SNOW CAPITAL MANAGEMENT LP | WESCO INTERNATIONAL INC | 2,209,169 | 5.2% | EDGAR |
| SC 13G/A | 2008-02-14 | FMR LLC | WESCO INTERNATIONAL INC | 1,961,041 | 4.5% | EDGAR |
| SC 13G/A | 2008-02-14 | GLENVIEW CAPITAL MANAGEMENT LLC | WESCO INTERNATIONAL INC | 1,319,666 | 3.0% | EDGAR |