| Name | Company Number | Date Appointed | Rating |
|---|---|---|---|
| Croeso Systems Development Ltd | 02624610 | 01/07/1999 | Dissolved |
| Daniel Pipelines Ltd | 02640107 | 19/03/2001 | Dissolved |
| Dawnleigh Ltd | 02661354 | 21/03/2001 | Dissolved |
| Dwr Cymru (Properties) Ltd | 03310610 | 21/03/2001 | Dissolved |
| Electricity Association Ltd | 02367010 | 21/05/2003 | Dissolved |
| Greenmile.Co.Uk Ltd. | 06050732 | 17/01/2007 | Dissolved |
| Hamdden Ltd | 02705531 | 21/03/2001 | Dissolved |
| Hyder Finance (1998) Ltd | FC021459 | 19/03/2001 | Dissolved |
| Hyder Finance (Holdings) Ltd | 03404913 | 19/03/2001 | Dissolved |
| Hyder Investments Overseas Holdings Ltd | 02958248 | 21/03/2001 | Dissolved |
| Hyder Overseas Investments Ltd | 02906578 | 21/09/2000 | Dissolved |
| Hyder Power Investments Ltd | 03405258 | 21/03/2001 | Dissolved |
| Hyder Property Developments Ltd | 04081160 | 26/09/2000 | Dissolved |
| Hyder Securities (Utilities) Ltd | 03310618 | 19/03/2001 | Dissolved |
| Hyder Services (Electricity) Ltd | 02624636 | 21/03/2001 | Dissolved |
| Hyder Services (Water) Ltd | 03116475 | 21/03/2001 | Dissolved |
| Hyder Utilities (Operations) Ltd | 03405264 | 21/03/2001 | Dissolved |
| Infralec Finance Ltd | 02817686 | 19/03/2001 | Dissolved |
| Infralec Financial Services Ltd | 02201425 | 19/03/2001 | Dissolved |
| Infralec Investments Ltd | 02624639 | 19/03/2001 | Dissolved |
| Infralec Telco Investments Ltd | 02837273 | 19/03/2001 | Dissolved |
| Llanishen Developments Ltd | 04302310 | 13/11/2001 | Dissolved |
| Lusis Ltd | 03049185 | 21/03/2001 | Dissolved |
| Mirant Asia-Pacific (Europe) Financial Services Ltd | 04242669 | 28/09/2001 | Dissolved |
| Mirant Asia-Pacific (Europe) Ltd | 04242673 | 28/09/2001 | Dissolved |
| Mirant Bahamas Holdings Ltd | 04252027 | 28/09/2001 | Dissolved |
| Mirant Global Finance Preferred Investments Ltd | 04251704 | 28/09/2001 | Dissolved |
| Pen Y Fan Properties (No. 2) Ltd | 02421859 | 21/03/2001 | Dissolved |
| Pen Y Fan Properties Ltd | 02805438 | 21/03/2001 | Dissolved |
| Pplg Europe Holdings Ii Ltd | 03532176 | 21/08/2003 | Dissolved |
| Southern Energy Investments | 03117354 | 29/05/2002 | Dissolved |
| Southern Energy Investments U K Plc | 03118397 | 29/05/2002 | Dissolved |
| Southern Energy Investments Uk Holdings Ltd | 03108637 | 29/05/2002 | Dissolved |
| St. Mellons Investments Ltd | 02212190 | 21/03/2001 | Dissolved |
| Temple Back Developments Ltd | 02901217 | 21/09/1995 | Dissolved |
| WELSH WATER INTERNATIONAL LIMITED | 02366589 | 21/03/2001 | Dissolved |
| Welsh Water Ltd | 03049158 | 21/05/2002 | Dissolved |
| Western Power Delivery Ltd | 03786093 | 29/05/2002 | Dissolved |
| Western Power Distribution Telecoms Ltd | 02720668 | 01/06/1999 | Dissolved |
| Western Power Ltd | 03786089 | 29/05/2002 | Dissolved |
| Western Power Networks Ltd | 02998246 | 01/10/1999 | Dissolved |
| Wpd Avonbank Ltd | 03786092 | 29/05/2002 | Dissolved |
| Wpd Energy Ltd | 02690236 | 01/10/1999 | Dissolved |
| Wpd Helicopter Unit Ltd | 02998269 | 01/10/1999 | Dissolved |
| Wpd Telecoms Ltd | 02998275 | 01/10/1999 | Dissolved |
| Wpdf Ltd | 04240850 | 09/08/2001 | Dissolved |
| Name | Company Number | Date Appointed | Date Resigned | Rating |
|---|---|---|---|---|
| ACER JOHN TAYLOR LIMITED | 01348874 | 15/09/2000 | 29/12/2000 | Dissolved |
| AVONBANK INVESTMENTS LIMITED | 04605120 | 10/12/2002 | 19/07/2007 | Gold |
| Acer Icf Ltd | 02534052 | 15/09/2000 | 29/12/2000 | Dissolved |
| Acer Services Ltd | 02220702 | 15/09/2000 | 29/12/2000 | Dissolved |
| Altwell Ltd | 01691929 | 15/09/2000 | 29/12/2000 | Dissolved |
| BUXTED CHICKEN LIMITED | 03055284 | 17/06/1996 | 17/06/1996 | Silver |
| Celtic Exterior Lighting Ltd | 02832856 | 15/09/2000 | 22/02/2001 | Dissolved |
| DREAMPHOTO LIMITED | 03055258 | 17/06/1996 | 17/06/1996 | Silver |
| DREAMPLAYER LIMITED | 03055269 | 17/06/1996 | 17/06/1996 | Silver |
| DWR CYMRU (FINANCING) LIMITED | FC023222 | 23/05/2001 | 23/05/2001 | Dissolved |
| DWR CYMRU (HOLDINGS) LIMITED | 03954867 | 24/01/2001 | 11/05/2001 | Silver |
| DWR CYMRU CYFYNGEDIG | 02366777 | 13/12/2000 | 11/05/2001 | Amber |
| EBUSINESS SOUTH WEST LIMITED | 03589882 | 01/04/2000 | 26/02/2002 | Gold |
| GDF SUEZ TEESSIDE LIMITED | 02464040 | 01/03/2004 | 27/04/2005 | Amber |
| Greenmile.Co.Uk Ltd. | 06050732 | 17/01/2007 | 29/06/2007 | Dissolved |
| HYDER INVESTMENTS LIMITED | 02898070 | 21/09/2000 | 26/01/2001 | Dissolved |
| HYDER LIMITED | 02366776 | 15/09/2000 | 31/03/2018 | Dissolved |
| Mirant Europe | 03187469 | 01/10/1999 | 11/09/2002 | Dissolved |
| Mirant Investments Uk Ltd | 03743976 | 01/06/1999 | 24/06/2002 | Dissolved |
| NG ELECTRICITY DISTRIBUTION LIMITED | FC023442 | 12/09/2001 | 31/03/2018 | Silver |
| PPL UK RESOURCES LIMITED | 04506336 | 30/08/2002 | 05/09/2002 | Silver |
| SOUTH WALES TPL INVESTMENTS LIMITED | 02579323 | 20/10/2000 | 04/12/2006 | Dissolved |
| Temple Back Developments Ltd | 02901217 | 06/06/1994 | 21/09/1995 | Dissolved |
| W T H Resourcing Ltd | 03353285 | 09/07/1997 | 30/09/1999 | Dissolved |
| WELSH WATER UTILITIES FINANCE PLC | 02869784 | 15/09/2000 | 11/05/2001 | Dissolved |
| WESTERN POWER INVESTMENTS LIMITED | 02579329 | 01/10/1999 | 03/07/2006 | Dissolved |
| WESTERN POWER PENSION TRUSTEE LIMITED | 02813866 | 14/08/1996 | 02/02/1999 | Not Trading |
| WP GENERATION LIMITED | 04605111 | 10/12/2002 | 19/07/2007 | Gold |
| Western Power Distribution Telecoms Ltd | 02720668 | 29/02/1996 | 30/07/1996 | Dissolved |