| Bureau of Transportation Tokyo Metropolitan Government |
| Central Japan Railway Company |
| Doden Co., Ltd. |
| East Japan Railway Company |
| Fujikyuko Co., Ltd. |
| Fukuoka City Transportation Bureau |
| Hankyu Hanshin Denki System K.K. |
| Hitachi, Ltd. |
| Hokkaido Railway Company |
| Japan Freight Railway Company |
| Japan Railway Construction Transport and Technology Agency |
| JR Kyushu Electric System Company |
| Kajima Corporation |
| KEPCO The Kansai Electric Power Co., Inc. |
| Kyushu Railway Company |
| Maeda Corporation |
| Ministry of Defense |
| NESCO |
| Nippon Densetsu Kogyo Co., Ltd. |
| Nippon Rietec Co., Ltd. |
| Nishimatsu Construction Co., Ltd. |
| Nishi-Nihon Tech Co., Ltd. |
| Obayashi Corporation |
| Odakyu Electric Railway Co., Ltd. |
| Osaka Municipal Transportation Bureau |
| Shikoku Railway Company |
| Shimizu Corporation |
| Shinsei Technos Co., Ltd. |
| Taisei Corporation |
| TEPCO |
| Tobu Railway Co., Ltd. |
| Toho Electrical Construction Company |
| Tokyo Metro Co., Ltd. |
| Tokyu Corporation |
| Total Electric Management Service Co., Ltd. |
| Transportation Bureau, City of Nagoya |
| Wako Filter Technology Ltd. |
| Wako Techno Ltd. |
| West Japan Railway Company |
