| Name | Company Number | Date Appointed | Rating |
|---|---|---|---|
| NUCLEAR RESTORATION SERVICES LIMITED | 02264251 | 01/09/2019 | Amber |
| RESEARCH SITES RESTORATION LIMITED | 05915837 | 01/09/2019 | Gold |
| THE LONDON INSTITUTE OF SPACE POLICY AND LAW | 07034158 | 01/03/2013 | Gold |
| Name | Company Number | Date Appointed | Date Resigned | Rating |
|---|---|---|---|---|
| ARQIVA MOBILE TV LIMITED | 04107732 | 20/11/2000 | 05/09/2001 | Amber |
| BRITISH NUCLEAR GROUP LIMITED | 05245506 | 01/04/2005 | 31/03/2007 | Silver |
| CABLE & WIRELESS ACCESS LIMITED | 04005262 | 11/10/2000 | 31/12/2002 | Dissolved |
| CAVENDISH NUCLEAR (OVERSEAS) LIMITED | 05339062 | 01/04/2005 | 31/03/2007 | Not Trading |
| DOUNREAY SITE RESTORATION LIMITED | SC307493 | 31/03/2021 | 01/04/2023 | Bronze |
| GEO METRO LIMITED | 04129122 | 21/02/2001 | 31/12/2002 | Dissolved |
| GREAT BRITISH NUCLEAR | 05027024 | 16/08/2005 | 31/03/2007 | Silver |
| NATIONAL GRID COMMERCIAL HOLDINGS LIMITED | 04042700 | 29/12/2001 | 31/12/2002 | Silver |
| NETWORK RAIL INFRASTRUCTURE LIMITED | 02904587 | 26/01/2010 | 18/07/2014 | Bronze |
| NETWORK RAIL LIMITED | 04402220 | 26/01/2010 | 18/07/2014 | Bronze |
| NGT TELECOM NO. 1 LIMITED | 03751494 | 21/09/2000 | 31/12/2002 | Dissolved |
| NGT TELECOM NO. 2 LIMITED | 04134417 | 19/02/2001 | 31/12/2002 | Dissolved |
| NUCLEAR RESTORATION SERVICES LIMITED | 02264251 | 18/03/2005 | 31/03/2007 | Amber |
| ON TOWER UK 1 LIMITED | 03922958 | 18/10/2000 | 21/10/2002 | Gold |
| OPTIMIZED SYSTEMS AND SOLUTIONS LIMITED | 03694885 | 02/01/2014 | 01/05/2015 | Dissolved |
| ROLLS-ROYCE CONTROLS AND DATA SERVICES LIMITED | 06686268 | 02/01/2014 | 13/11/2015 | Not Trading |
| ROLLS-ROYCE SUBMARINES LIMITED | 00620485 | 15/05/2009 | 26/04/2016 | Silver |
| SELLAFIELD LIMITED | 01002607 | 02/05/2024 | 30/06/2024 | Silver |
| TELECOM INTERNATIONAL HOLDINGS LIMITED | 03999215 | 29/08/2000 | 31/12/2002 | Dissolved |
| TETRA TECH ENVIRONMENT PLANNING TRANSPORT LIMITED | 03050297 | 18/06/2007 | 05/01/2009 | Not Trading |
| TETRA TECH GROUP LIMITED | 06595608 | 16/05/2008 | 06/01/2009 | One Red Flag |
| TETRA TECH LIMITED | 01959704 | 18/06/2007 | 05/01/2009 | Silver |
| TETRA TECH MANAGEMENT SERVICES LIMITED | 04807864 | 18/06/2007 | 05/01/2009 | Not Trading |
| TETRA TECH UK CONSULTING GROUP LIMITED | 01869543 | 18/06/2007 | 05/01/2009 | Silver |
| THE ROYAL AIR FORCE BENEVOLENT FUND | ZC000201 | 15/11/2005 | 27/01/2022 | Silver |
| WYG INTERNATIONAL LIMITED | 03195485 | 18/06/2007 | 05/01/2009 | Dissolved |