| Name | Company Number | Date Appointed | Rating |
|---|---|---|---|
| Club Athletica (Worcester) Ltd | 02152388 | 29/10/2002 | Dissolved |
| Community Leisure Management Ltd | 02163239 | 20/09/2002 | Dissolved |
| London Call Centre Co Ltd | 03334238 | 20/09/2002 | Dissolved |
| Serco Development Services Ltd | 00592499 | 20/09/2002 | Dissolved |
| Serco Inactive 1 Ltd | 02269522 | 02/12/2002 | Dissolved |
| Serco Inactive 4 Ltd | 00850447 | 20/09/2002 | Dissolved |
| Serco Maintenance Services Ltd | 02674902 | 20/09/2002 | Dissolved |
| Serco Operations Ltd | 01858592 | 30/10/2002 | Dissolved |
| Serco Research & Development Ltd | 02736437 | 14/05/2003 | Dissolved |
| Serco Test Technology Ltd | 01413253 | 30/10/2002 | Dissolved |
| Superbusy Ltd | 02533020 | 20/09/2002 | Dissolved |
| Name | Company Number | Date Appointed | Date Resigned | Rating |
|---|---|---|---|---|
| AVEN TOOLS LIMITED | 00989959 | 02/05/2000 | 21/12/2000 | Gold |
| AVEN TOOLS LIMITED | 00989959 | 02/05/2000 | 28/02/2001 | Gold |
| BANDHART | 01518375 | 02/05/2000 | 21/12/2000 | Amber |
| BANDHART | 01518375 | 02/05/2000 | 28/02/2001 | Amber |
| BANDHART OVERSEAS | 00478319 | 02/05/2000 | 21/12/2000 | Gold |
| BANDHART OVERSEAS | 00478319 | 02/05/2000 | 28/02/2001 | Gold |
| BLACK & DECKER | 00291547 | 02/05/2000 | 11/12/2000 | Amber |
| BLACK & DECKER | 00291547 | 02/05/2000 | 28/02/2001 | Amber |
| BLACK & DECKER BATTERIES MANAGEMENT LIMITED | 02238517 | 02/05/2000 | 21/12/2000 | Insolvent |
| BLACK & DECKER BATTERIES MANAGEMENT LIMITED | 02238517 | 02/05/2000 | 28/02/2001 | Insolvent |
| BLACK & DECKER EUROPE | 01842628 | 02/05/2000 | 29/01/2001 | Silver |
| BLACK & DECKER EUROPE | 01842628 | 02/05/2000 | 28/02/2001 | Silver |
| BLACK & DECKER FINANCE | 01113037 | 02/05/2000 | 21/12/2000 | One Red Flag |
| BLACK & DECKER GROUP, LLC | FC011130 | 02/05/2000 | 21/12/2000 | Silver |
| BLACK & DECKER GROUP, LLC | FC011130 | 02/05/2000 | 28/02/2001 | Silver |
| BLACK & DECKER HOLDINGS, LLC | FC010559 | 02/05/2000 | 29/01/2001 | Silver |
| BLACK & DECKER HOLDINGS, LLC | FC010559 | 02/05/2000 | 28/02/2001 | Silver |
| BLACK & DECKER INTERNATIONAL | 00209797 | 02/05/2000 | 29/01/2001 | Silver |
| BLACK & DECKER INTERNATIONAL | 00209797 | 02/05/2000 | 28/02/2001 | Silver |
| BLACK & DECKER INVESTMENT COMPANY, LLC | FC010558 | 02/05/2000 | 21/12/2000 | Gold |
| DEWALT INDUSTRIAL POWER TOOL COMPANY LTD. | SC014586 | 02/05/2000 | 11/12/2000 | Amber |
| DEWALT INDUSTRIAL POWER TOOL COMPANY LTD. | SC014586 | 02/05/2000 | 28/02/2001 | Amber |
| ELU POWER TOOLS LTD | 01740007 | 02/05/2000 | 11/12/2000 | Amber |
| ELU POWER TOOLS LTD | 01740007 | 02/05/2000 | 28/02/2001 | Amber |
| Kilmarnock Prison (Holdings) Ltd | 03443465 | 15/02/2006 | 21/07/2006 | Dissolved |
| Medomsley Holdings Ltd | 03488629 | 15/02/2006 | 21/07/2006 | Dissolved |
| Moreton Prison (Holdings) Ltd | 03471078 | 15/02/2006 | 21/07/2006 | Dissolved |
| Prime Contractors Ltd | 02378246 | 20/09/2002 | 21/07/2006 | Dissolved |
| SERCO LIMITED | 00242246 | 29/07/2003 | 27/07/2006 | Silver |
| SERCO REGIONAL SERVICES LIMITED | 01653016 | 11/10/2001 | 21/07/2006 | One Red Flag |
| SERCO-IAL LIMITED | 00427272 | 10/10/2002 | 21/07/2006 | Silver |
| SPECIALIST FLEET SERVICES LIMITED | 02843547 | 08/03/2002 | 31/07/2002 | Bronze |
| Serco Contracting Ltd | 02435848 | 20/09/2002 | 21/07/2006 | Dissolved |
| Serco Leisure Ltd | 02202587 | 20/09/2002 | 21/07/2006 | Dissolved |
| Serco Project Development Ltd | 02834872 | 29/10/2002 | 21/07/2006 | Dissolved |
| Serco Systems Ltd | 01861237 | 10/10/2002 | 21/07/2006 | Dissolved |
| Sercoserve Ltd | 02497013 | 20/09/2002 | 21/07/2006 | Dissolved |