| Name | Company Number | Date Appointed | Rating |
|---|---|---|---|
| WILLIAM COOK BURTON LIMITED | 00443199 | 23/06/2003 | Insolvent |
| WILLIAM COOK FOUNDRY (TOW LAW) LIMITED | 00133373 | 15/04/1997 | Insolvent |
| WILLIAM COOK MACHINE SHOP (TOW LAW) LIMITED | 03576124 | 13/01/2000 | Dissolved |
| WILLIAM COOK SHEFFIELD LIMITED | 02100070 | 01/12/2001 | Dissolved |
| Name | Company Number | Date Appointed | Date Resigned | Rating |
|---|---|---|---|---|
| COOK DEFENCE SYSTEMS LIMITED | 06792266 | 24/09/2012 | 01/07/2015 | Amber |
| GLENTWORTH RAIL LIMITED | 05324577 | 28/06/2013 | 01/07/2015 | Dissolved |
| WILLIAM COOK (MS) 2018 LIMITED | 00053475 | 01/05/1995 | 01/07/2015 | Dissolved |
| WILLIAM COOK CAST PRODUCTS LIMITED | 02727560 | 01/05/1995 | 01/07/2015 | Bronze |
| WILLIAM COOK HOLDINGS LIMITED | 03283010 | 18/07/2013 | 16/10/2015 | Silver |
| WILLIAM COOK INTEGRITY LIMITED | 02070684 | 17/10/2002 | 01/07/2015 | Dissolved |
| WILLIAM COOK INTERMODAL LIMITED | 01483687 | 01/11/2011 | 01/07/2015 | Amber |
| WILLIAM COOK LEEDS LIMITED | 02727561 | 13/01/2000 | 01/07/2015 | One Red Flag |
| WILLIAM COOK LIMITED | 00074837 | 01/10/1998 | 01/07/2015 | Not Trading |
| WILLIAM COOK MASTER PATTERNS LIMITED | 02610170 | 23/06/2003 | 01/07/2015 | Dissolved |
| WILLIAM COOK NDT LIMITED | 01011570 | 23/06/2003 | 12/11/2003 | Dissolved |
| WILLIAM COOK NDT LIMITED | 01011570 | 12/11/2003 | 01/07/2015 | Dissolved |
| WILLIAM COOK PRECISION LIMITED | 00533243 | 04/04/2002 | 01/07/2015 | Dissolved |
| WILLIAM COOK RAIL LIMITED | 08694277 | 28/03/2014 | 01/07/2015 | Bronze |
| WILLIAM COOK STANHOPE LIMITED | 00359586 | 01/11/2011 | 01/07/2015 | Bronze |