1. Toda Corporation
2. Better Living
3. Asanuma Corporation
4. Okumura Corporation
5. Kumagaigumi Co., Ltd.
6. Penta-Ocean Construction Co., Ltd.
7. Sato Kogyo Co., Ltd.
8. SEIBU Construction Co., Ltd.
9. Toa Corporation
10. Tokyo Soil Research Co., Ltd.
11. Nishimatsu Construction Co.
12. HASEKO Corporation
13. MATSUMURA-GUMI Corporation