Exhibit 21.1

Project Tennis Entity List

The ADT Corporation (a Delaware corporation)

Country |  | Entity |  | State |
Canada |  | ADT Security Services Canada, Inc. * |  |  |  |
Gibraltar |  | Tyco International (Gibraltar) III Limited |  |  |  |
Puerto Rico |  | ADT Puerto Rico, Inc. |  |  |  |
United States |  | ADT Canada Holdings, Inc. |  |  | DE |
United States |  | ADT Holdings, Inc. |  |  | DE |
United States |  | ADT Investments, Inc. |  |  | DE |
United States |  | ADT LLC |  |  | DE |
United States |  | ADT US Holdings, Inc. |  |  | DE |
United States |  | Barricade Merger Sub, Inc. |  |  | NV |
United States |  | Electro Signal Lab, Inc. |  |  | DE |
United States |  | S2 Mergersub Inc. |  |  | NJ |

* | Post spin-off, name is expected to change to ADT Canada, Inc.