EXHIBIT 11

TELLABS, INC.

COMPUTATION OF PER SHARE EARNINGS

In millions, except per share amounts



|                                                                                                                                                                                                                                                                                                                                                                                                                                                     |  |               |       |         |             |        |         |  |         |       |  |   |        |  
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |  | ------------- | ----- | ------- | ----------- | ------ | ------- |  | ------- | ----- |  | - | ------ | -
|                                                                                                                                                                                                                                                                                                                                                                                                                                                     |  | Third Quarter |       |         | Nine Months |       
|                                                                                                                                                                                                                                                                                                                                                                                                                                                     |  | 10/2/09       |       | 9/26/08 |             |        | 10/2/09 |  | 9/26/08 |      
|Numerator:                                                                                                                                                                                                                                                                                                                                                                                                                                           |  |               |       |         |             |        |         |  |         |       |  |   |        |  
|Net earnings (loss)                                                                                                                                                                                                                                                                                                                                                                                                                                  |  | $             | 29.3  |         | $           | (998.5 | )       |  | $       | 51.5  |  | $ | (942.9 | )
|                                                                                                                                                                                                                                                                                                                                                                                                                                                     |  |               |       |         |             |        |         |  |         |       |  |   |        |  
|                                                                                                                                                                                                                                                                                                                                                                                                                                                     |  |               |       |        
|Denominator:                                                                                                                                                                                                                                                                                                                                                                                                                                         |  |               |       |         |             |        |         |  |         |       |  |   |        |  
|                                                                                                                                                                                                                                                                                                                                                                                                                                                     |  |               |       |        
|Denominator for basic earnings per share -                                                                                                                                                                                                                                                                                                                                                                                                           |  |               |       |         |             |        |         |  |         |       |  |   |        |  
|Weighted average shares outstanding                                                                                                                                                                                                                                                                                                                                                                                                                  |  |               | 392.3 |         |             | 398.0  |         |  |         | 394.8 |  |   | 401.1  |  
|                                                                                                                                                                                                                                                                                                                                                                                                                                                     |  |               |       |        
|Effect of dilutive securities:                                                                                                                                                                                                                                                                                                                                                                                                                       |  |               |       |         |             |        |         |  |         |       |  |   |        |  
|                                                                                                                                                                                                                                                                                                                                                                                                                                                     |  |               |       |        
|Stock options and awards                                                                                                                                                                                                                                                                                                                                                                                                                             |  |               | 1.9   |         |             |       |         |  |         | 1.3   |  |   |       |  
|                                                                                                                                                                                                                                                                                                                                                                                                                                                     |  |               |       |         |             |        |         |  |         |       |  |   |        |  
|Denominator for diluted earnings per share -                                                                                                                                                                                                                                                                                                                                                                                                         |  |               |       |         |             |        |         |  |         |       |  |   |        |  
|Adjusted weighted average shares outstanding and assumed conversions                                                                                                                                                                                                                                                                                                                                                                                 |  |               | 394.2 |         |             | 398.0  |         |  |         | 396.1 |  |   | 401.1  |  
|                                                                                                                                                                                                                                                                                                                                                                                                                                                     |  |               |       |         |             |        |         |  |         |       |  |   |        |  
|                                                                                                                                                                                                                                                                                                                                                                                                                                                     |  |               |       |        
|Net earnings (loss) per share  basic                                                                                                                                                                                                                                                                                                                                                                                                                |  | $             | 0.07  |         | $           | (2.51  | )       |  | $       | 0.13  |  | $ | (2.35  | )
|                                                                                                                                                                                                                                                                                                                                                                                                                                                     |  |               |       |         |             |        |         |  |         |       |  |   |        |  
|Net earnings (loss) per share  diluted                                                                                                                                                                                                                                                                                                                                                                                                              |  | $             | 0.07  |         | $           | (2.51  | )       |  | $       | 0.13  |  | $ | (2.35  | )
|                                                                                                                                                                                                                                                                                                                                                                                                                                                     |  |               |       |         |             |        |         |  |         |       |  |   |        |  
|                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|The number of anti-dilutive securities excluded from the weighted average shares outstanding computation was
26.9 million in the third quarter of 2009, 31.9 million for the first nine months of 2009, 34.8 million in the third quarter of 2008, and 35.6 million for the first nine months of 2008.  Under U.S. GAAP, dilutive securities are not included in the computation of diluted
earnings per share when a company is in a loss position. |