EXHIBIT 11

TELLABS, INC.

COMPUTATION OF PER SHARE EARNINGS

In millions, except per share amounts



|                                                                                                                                                                                                                                                                                                       |  |                |       |            |   |        |  |         |       |  |   |      
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |  | -------------- | ----- | ---------- | - | ------ |  | ------- | ----- |  | - | -----
|                                                                                                                                                                                                                                                                                                       |  | Second Quarter |       | Six Months
|                                                                                                                                                                                                                                                                                                       |  | 7/3/09         |       | 6/27/08    |   | 7/3/09 |  | 6/27/08
|Numerator:                                                                                                                                                                                                                                                                                             |  |                |       |            |   |        |  |         |       |  |   |      
|Net earnings                                                                                                                                                                                                                                                                                           |  | $              | 15.7  |            | $ | 39.0   |  | $       | 22.2  |  | $ | 55.6 
|                                                                                                                                                                                                                                                                                                       |  |                |       |            |   |        |  |         |       |  |   |      
|                                                                                                                                                                                                                                                                                                       |  |                |       |           
|Denominator:                                                                                                                                                                                                                                                                                           |  |                |       |            |   |        |  |         |       |  |   |      
|                                                                                                                                                                                                                                                                                                       |  |                |       |           
|Denominator for basic earnings per share -                                                                                                                                                                                                                                                             |  |                |       |            |   |        |  |         |       |  |   |      
|Weighted average shares outstanding                                                                                                                                                                                                                                                                    |  |                | 396.2 |            |   | 397.5  |  |         | 396.0 |  |   | 402.7
|                                                                                                                                                                                                                                                                                                       |  |                |       |           
|Effect of dilutive securities:                                                                                                                                                                                                                                                                         |  |                |       |            |   |        |  |         |       |  |   |      
|                                                                                                                                                                                                                                                                                                       |  |                |       |           
|Stock options and awards                                                                                                                                                                                                                                                                               |  |                | 1.4   |            |   | 1.0    |  |         | 1.2   |  |   | 0.9  
|                                                                                                                                                                                                                                                                                                       |  |                |       |            |   |        |  |         |       |  |   |      
|Denominator for diluted earnings per share -                                                                                                                                                                                                                                                           |  |                |       |            |   |        |  |         |       |  |   |      
|Adjusted weighted average sharesoutstanding and assumed conversions                                                                                                                                                                                                                                    |  |                | 397.6 |            |   | 398.5  |  |         | 397.2 |  |   | 403.6
|                                                                                                                                                                                                                                                                                                       |  |                |       |            |   |        |  |         |       |  |   |      
|                                                                                                                                                                                                                                                                                                       |  |                |       |           
|Net earnings per share  basic                                                                                                                                                                                                                                                                         |  | $              | 0.04  |            | $ | 0.10   |  | $       | 0.06  |  | $ | 0.14 
|                                                                                                                                                                                                                                                                                                       |  |                |       |            |   |        |  |         |       |  |   |      
|Net earnings per share  diluted                                                                                                                                                                                                                                                                       |  | $              | 0.04  |            | $ | 0.10   |  | $       | 0.06  |  | $ | 0.14 
|                                                                                                                                                                                                                                                                                                       |  |                |       |            |   |        |  |         |       |  |   |      
|The number of anti-dilutive securities excluded from the weighted
average shares outstanding computation was 31.8 million in the second quarter of 2009, 32.2 million for the first six months of 2009, 35.7 million in the second quarter of 2008, and 35.8 million for the first six months of 2008.