**Exhibit 12**

**Agere    Systems Inc. and Subsidiaries    Ratio of Earnings to Fixed Charges**

|                                         |                                                                |                                   | Year Ended September        30, |
|----------------------------------------------|---------------------------------------------------------------------|----------------------------------------|---------------------------------|
|                                         |                                                                |                                   | 2005                            |   | 2004 |   | 2003 |   | 2002 |   | 2001 |
|                                         |                                                                |                                   | (dollars in millions)           |
| Earnings        available for fixed charges: |                                                                |                                   |                            |   |   | *** *** |   | *** *** |   | *** *** |
|                | Income (loss) from        continuing operations before income taxes | *      * | $        (130                   | )     | $        (150 | )     | $        (325 | )     | $        (740 | )     | $        (1,343 | )     |
|                                         | Less        undistributed equity earnings (loss) from investments   | * *                               | (10                             | )     | (5 | )     | 13 | * * | 40 | * * | 42 |
|                                         | Less        interest capitalized during the period                  |                                   | -                               |   | - |   | - |   | 5 |   | 4 |
|                                         | Add        distributed income of equity investees                   |                                   | 41                              |   | 61 |   | - |   | - |   | - |
|                                         | Add        fixed charges                                            |                                   | 46                              |   | 67 |   | 77 |   | 168 |   | 199 |
|                                         | Total        earnings available for fixed charges                   |                                   | $          (33        | )     | $          (17 | )     | $        (261 | )     | $        (617 | )     | $        (1,190 | )     |
|                                         |                                                                |                                   |                            |   |   |   |   |   |   |   |   |
| Fixed        charges:                        |                                                                |                                   |                            |   |   |   |   |   |   |   |
|                                         | Interest        expense including capitalized interest              |                                   | $           29   |   | $           43 |   | $           47 |   | $          126 |   | $            155 |
|                                         | Interest        portion of rental expense                           |                                   | 17                              |   | 24 |   | 30 |   | 42 |   | 44 |
|                                         | Total        fixed charges                                          |                                   | $           46   |   | $           67 |   | $           77 |   | $          168 |   | $            199 |
|                                         |                                                                |                                   |                            |   |   |   |   |   |   |   |   |
| Ratio        of earnings to fixed charges    |                                                                | n/a                                    |                            | n/a |   | n/a |   | n/a |   | n/a |
| Deficiency                                   |                                                                | $           79          |                            | $           84 |   | $         338 |   | $          785 |   | $         1,389 |