**Exhibit 21**

 

**Simpson Manufacturing Co., Inc. andSubsidiaries**

**List of Subsidiaries of Simpson Manufacturing Co., Inc.**

##### **At February 26, 2010**

##### ** **

| 1.          | Simpson Strong-Tie  Company Inc., a California corporation                      |
|-------------|---------------------------------------------------------------------------------|
|        |                                                                            |
| 2.          | Simpson Dura-Vent  Company, Inc., a California corporation                 |
|        |                                                                            |
| 3.          | Simpson Strong-Tie  International, Inc., a California corporation          |
|        |                                                                            |
| 4.          | Simpson Strong-Tie  Canada, Limited, a Canadian corporation                     |
|        |                                                                            |
| 5.          | Simpson Strong-Tie  Europe EURL, a French corporation                           |
|        |                                                                            |
| 6.          | Simpson Strong-Tie,  S.A.S., a French corporation                               |
|        |                                                                            |
| 7.          | Simpson Strong-Tie  Japan, Inc., a California corporation                  |
|        |                                                                            |
| 8.          | Simpson Strong-Tie  Australia, Inc., a California corporation              |
|        |                                                                            |
| 9.          | ****Simpson Strong-Tie A/S****, a Danish corporation                            |
|        |                                                                            |
| 10.         | ****Simpson Strong-Tie GmbH****, a German corporation                           |
|        |                                                                            |
| ****11.**** | ****Simpson Strong-Tie Sp.z,o.o.****, a Polish corporation                      |
|        |                                                                            |
| ****12.**** | ****Simpson France**** SCI, a French corporation                                |
|        |                                                                            |
| 13.         | ATF GmbH, a Swiss  corporation                                                  |
|        |                                                                            |
| 14.         | Simpson Strong-Tie  Australia Pty Limited, an Australian corporation            |
|        |                                                                            |
| 15.         | Simpson Strong-Tie  Mexico, S. de R.L. de C.V., a Mexican corporation           |
|        |                                                                            |
| 16.         | Simpson Manufacturing  Cyprus Limited, a Cyprus limited liability company       |
|        |                                                                            |
| 17.         | Simpson Strong-Tie Asia  Limited, a Hong Kong company                           |
|        |                                                                            |
| 18.         | Simpson Strong-Tie Asia  Holding Limited, a Hong Kong company                   |
|        |                                                                            |
| 19.         | Simpson Strong-Tie  (Beijing) Company Limited, a Chinese company                |
|        |                                                                            |
| 20.         | Simpson Strong-Tie  (Zhangjiagang) Co., Ltd., a Chinese company                 |
|        |                                                                            |
| 21.         | Simpson Strong-Tie  Ireland Limited, an Irish company                           |
|        |                                                                            |
| 22.         | Ahorn-Geräte & Werkzeuge Vertriebs GmbH, a German company         |
|        |                                                                            |
| 23.         | Simpson Strong-Tie  s.r.o., a Czech company                                     |
|        |                                                                            |
| 24.         | Agence Internationale  Commerciale Et Industrielle, S.A.S, a French corporation |
|        |                                                                            |
| 25.         | Societe Civile  Immobiliere IMAG SCI, a French corporation                      |

 

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