| Name | Company Number | Date Appointed | Rating |
|---|
| Name | Company Number | Date Appointed | Date Resigned | Rating |
|---|---|---|---|---|
| Agsl Ltd | 02370626 | 11/04/1992 | 31/07/1992 | Dissolved |
| Global One Communications Operations | 02172910 | 10/05/1991 | 31/07/1992 | Dissolved |
| KWIKFORM HOLDINGS LIMITED | 00391476 | 06/11/1992 | 01/07/1993 | Dissolved |
| RICARDO PLC | 00222915 | 01/10/2003 | 18/11/2009 | Silver |
| RMD KWIKFORM LIMITED | 00301199 | 06/11/1992 | 01/07/1993 | Gold |
| SIEMENS BENEFITS SCHEME LIMITED | 02543236 | 18/03/1992 | 31/07/1992 | Not Trading |
| SIEMENS PUBLIC LIMITED COMPANY | 00727817 | 18/03/1992 | 18/03/1993 | Silver |
| SPIRENT COMMUNICATIONS PLC | 00470893 | 21/05/1999 | 22/12/2006 | Silver |
| Siemens Controls Ltd | 02473064 | 18/06/1991 | 08/06/1992 | Dissolved |
| Siemens Transportation Systems Ltd | 02702102 | 01/05/1992 | 31/07/1992 | Dissolved |
| Traffic Systems International Ltd | 00372520 | 03/03/1992 | 07/07/1992 | Dissolved |