| Name | Company Number | Date Appointed | Rating |
|---|---|---|---|
| CONSERVATHERM LIMITED | 02027751 | 14/10/1998 | Dissolved |
| F C S Technologies Ltd | 04330422 | 05/12/2001 | Dissolved |
| F.C.S. DIXON LIMITED | 04441187 | 08/11/2002 | Dissolved |
| FCS ENERGY LIMITED | 02256942 | 01/01/1998 | Dissolved |
| MODERN REFRACTORIES LIMITED | 07731562 | 05/08/2011 | Dissolved |
| Name | Company Number | Date Appointed | Date Resigned | Rating |
|---|---|---|---|---|
| FCS INVESTMENTS LIMITED | 07109987 | 21/12/2009 | 08/02/2024 | One Red Flag |
| FUEL CONSERVATION SERVICES LIMITED | 01545906 | 01/01/1998 | 08/02/2024 | Silver |