Exhibit 12.1
The ADT Corporation
Computation of Ratio of Earnings to Fixed Charges
(dollars in millions)

|  | Six Months Ended |  | Fiscal Year Ended
|  | March 31, 2016 |  | September 25, 2015 |  | September 26, 2014 |  | September 27, 2013 |  | September 28, 2012 |  | September 30, 2011
| Earnings: |  |  |  |  |  |  |  |  |  |  |
| Income from continuing operations before income taxes | $ | 182 |  |  | $ | 437 |  |  | $ | 432 |  |  | $ | 642 |  |  | $ | 630 |  |  | $ | 604 |
Add: | Fixed charges | 112 |  |  | 220 |  |  | 205 |  |  | 128 |  |  | 108 |  |  | 103 |
| Total earnings as adjusted | $ | 294 |  |  | $ | 657 |  |  | $ | 637 |  |  | $ | 770 |  |  | $ | 738 |  |  | $ | 707 |
| Fixed Charges(1): |  |  |  |  |  |  |  |  |  |  |
| Interest expense | $ | 107 |  |  | $ | 209 |  |  | $ | 193 |  |  | $ | 118 |  |  | $ | 93 |  |  | $ | 90 |
| Interest component of rental expense | 5 |  |  | 11 |  |  | 12 |  |  | 10 |  |  | 15 |  |  | 13 |
| Total fixed charges | $ | 112 |  |  | $ | 220 |  |  | $ | 205 |  |  | $ | 128 |  |  | $ | 108 |  |  | $ | 103 |
| Ratio of earnings to fixed charges | 2.6 |  |  | 3.0 |  |  | 3.1 |  |  | 6.0 |  |  | 6.8 |  |  | 6.9 |

(1) | Fixed charges represent amounts relating to continuing operations. Interest expense included in the computation of fixed charges includes the amortization of debt discounts and amortization of capitalized expenses related to indebtedness. Interest related to unrecognized tax benefits is recognized in income tax expense. The interest component of rent expense is based on an appropriate interest factor on operating leases.