| Name | Company Number | Date Appointed | Rating |
|---|---|---|---|
| A P L ENGINEERING LIMITED | 02728504 | 31/01/1994 | Dissolved |
| A P L ENGINEERING LIMITED | 02728504 | 03/07/1992 | Dissolved |
| A.P.L. LINEAR SYSTEMS LIMITED | 02823513 | 01/02/1994 | Dissolved |
| A.P.L. LINEAR SYSTEMS LIMITED | 02823513 | 02/06/1993 | Dissolved |
| APL GROUP (HOLDINGS) LIMITED | 02938773 | 14/06/1994 | Dissolved |
| CLEARWELL ENERGY LIMITED | 07430686 | 05/11/2010 | Bronze |
| Chiltern Instruments Ltd | 01600749 | 29/04/1993 | Dissolved |
| KULICIDE LIMITED | 08941752 | 16/05/2014 | One Red Flag |
| Lightseal Ltd | 05504220 | 05/08/2005 | Dissolved |
| London & County Developments Ltd | 03150301 | 24/01/1996 | Dissolved |
| MONITORING SERVICES (U.K.) LIMITED | 03634432 | 23/09/1998 | One Red Flag |
| MSL GROUP HOLDINGS LTD | 05689977 | 27/01/2006 | Silver |
| MSL OILFIELD SERVICES LTD | 05690012 | 27/01/2006 | Silver |
| MSL VENTURES LTD | 07010494 | 07/09/2009 | Dissolved |
| Msl-Clearwell Ltd | 05157907 | 22/09/2005 | Dissolved |
| NDI (SOUTHERN) LIMITED | 08921298 | 04/03/2014 | Dissolved |
| Offshore Monitoring Services (Aberdeen) Ltd | SC088671 | 12/06/1989 | Dissolved |
| Old Barn Developments Ltd | 04222682 | 23/05/2001 | Dissolved |
| Old Barn Inns Ltd | 05077154 | 01/11/2004 | Dissolved |
| Name | Company Number | Date Appointed | Date Resigned | Rating |
|---|---|---|---|---|
| CLEARWELL INTERNATIONAL LIMITED | 05196403 | 22/11/2004 | 17/01/2011 | Gold |
| FUNKI BARN LTD | 05352956 | 04/02/2005 | 29/02/2008 | One Red Flag |
| FUNKI BARN LTD | 05352956 | 11/03/2005 | 29/02/2008 | One Red Flag |
| M I A INVESTMENTS LIMITED | 05424479 | 14/04/2005 | 28/02/2008 | Amber |
| Old Barn Inns Ltd | 05077154 | 18/03/2004 | 23/03/2004 | Dissolved |
| PACTDALE LIMITED | 01090712 | 29/11/2001 | 04/02/2002 | Dissolved |
| STRATECH LIMITED | 06932978 | 12/08/2009 | 29/02/2012 | Dissolved |