|                                                                                 |   | Nine MonthsEndedSeptember 30, |   | Years Ended December 31, |   |
|--------------------------------------------------------------------------------------|--------|------------------------------------|--------|-------------------------------|--------|
|                                                                                 |   | 2011                               |   | 2010                          |   | 2009 |   | 2008 |   | 2007 |   | 2006 |   |
| Determination of earnings (loss):                                                    |   |                               |   |                          |   |   |   |   |   |   |   |   |   |
| Income (loss) from operations(1)                                                     |   | $                                  | 21,127 |                          | $      | (69,820 | ) | $ | (30,612 | ) | $ | (44,672 | ) | $ | (43,688 | ) | $ | (21,497 | ) |
| Add:                                                                                 |   |                               |   |                          |   |   |   |   |   |   |   |   |   |
| Fixed charges                                                                        |   | 492                                |   | 709                           |   | 555 |   | 594 |   | 483 |   | 339 |   |
|                                                                                 |   |                               |   |                          |   |   |   |   |   |   |   |   |   |
| Earnings (loss), as adjusted                                                         |   | $                                  | 21,619 |                          | $      | (69,111 | ) | $ | (30,057 | ) | $ | (44,078 | ) | $ | (43,205 | ) | $ | (21,158 | ) |
|                                                                                 |   |                               |   |                          |   |   |   |   |   |   |   |   |   |
| Fixed charges:                                                                       |   |                               |   |                          |   |   |   |   |   |   |   |   |   |
|                                                                                 |   |                               |   |                          |   |   |   |   |   |   |   |   |   |
| Estimate of interest within rental expense                                           |   | 492                                |   | 709                           |   | 555 |   | 594 |   | 483 |   | 339 |   |
|                                                                                 |   |                               |   |                          |   |   |   |   |   |   |   |   |   |
| Fixed charges                                                                        |   | $                                  | 492    |                          | $      | 709 |   | $ | 555 |   | $ | 594 |   | $ | 483 |   | $ | 339 |   |
|                                                                                 |   |                               |   |                          |   |   |   |   |   |   |   |   |   |
| Preferred stock dividends                                                            |   | $                                  | -      |                          | $      | - |   | $ | - |   | $ | - |   | $ | - |   | $ | - |   |
|                                                                                 |   |                               |   |                          |   |   |   |   |   |   |   |   |   |
|                                                                                 |   |                               |   |                          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Ratio of earnings (loss) to fixed charges and preferred stock dividends              |   | 44                                 |   | *                             |   | * |   | * |   | * |   | * |   |
| Coverage deficiency amount for total fixed charges and preferred stock dividends (2) |   |                               | -      |                          | $      | 69,820 |   | $ | 30,612 |   | $ | 44,672 |   | $ | 43,688 |   | $ | 21,497 |   |

| (2) | For the full years presented, the Company’s coverage ratio is less than one-to-one and it must generate additional earnings of these specified amounts to achieve a coverage ratio of 1:1. |
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