- Nippon Telegraph and Telephone Corporation
- NEC Corporation
- Fujitsu Laboratories Ltd.
- Furukawa Electric Co., Ltd.
- Mitsubishi Electric Company
- Oki Electric Industry Co., Ltd.
- Hitachi, Ltd. (join Mar. 2003)
- Keio University (join Apr. 2004)
- IP Infusion Inc. (join Aug. 2004)