| Name | Company Number | Date Appointed | Rating |
|---|---|---|---|
| Buttonbeach Ltd | 05294505 | 14/12/2004 | Dissolved |
| Buttonbrick Ltd | 05294240 | 14/12/2004 | Dissolved |
| Cobra (Wood Treatment) Ltd | 01684887 | 20/09/2007 | Dissolved |
| Croon Ltd | SC057822 | 20/09/2007 | Dissolved |
| Foldermast Ltd | 05294228 | 14/12/2004 | Dissolved |
| Foldermodel Ltd | 05294177 | 14/12/2004 | Dissolved |
| Graeme N.Russell Precision Ltd | 01149088 | 20/09/2007 | Dissolved |
| H.T. ROBERTSON & CO. LIMITED | SC033480 | 06/05/2009 | Dissolved |
| H.T. ROBERTSON & CO. LIMITED | SC033480 | 20/09/2007 | Dissolved |
| Hoplex Alpha Ltd | 00108508 | 20/09/2007 | Dissolved |
| Hoplex Bravo Ltd | 01386734 | 20/09/2007 | Dissolved |
| Hoplex Charlie Ltd | 00342718 | 20/09/2007 | Dissolved |
| Hoplex Delta Ltd | 02585319 | 20/09/2007 | Dissolved |
| Hoplex Echo Ltd | 00314713 | 20/09/2007 | Dissolved |
| Hoplex Foxtrot Ltd | 01474039 | 20/09/2007 | Dissolved |
| Launchrate Ltd | 05290144 | 14/12/2004 | Dissolved |
| Launchstamp Ltd | 05294236 | 14/12/2004 | Dissolved |
| Metrosonics Ltd | 02476478 | 20/09/2007 | Dissolved |
| Modelplant Ltd | 05290142 | 14/12/2004 | Dissolved |
| Monitor Labs Ltd | 03086483 | 20/09/2007 | Dissolved |
| PG DATA TECHNOLOGY LIMITED | 00843902 | 20/09/2007 | Insolvent |
| Pg Blackwood Ltd | 00843904 | 20/09/2007 | Dissolved |
| Pg Electronic Components Ltd | 02097629 | 20/09/2007 | Dissolved |
| Pg Inductive Technology Ltd | 02097627 | 20/09/2007 | Dissolved |
| Pg Ltd | 00936364 | 20/09/2007 | Dissolved |
| Pg Position Sensors Ltd | 02272968 | 20/09/2007 | Dissolved |
| Pg Transducers Ltd | 00843905 | 20/09/2007 | Dissolved |
| Phonehill Ltd | 05294175 | 14/12/2004 | Dissolved |
| Power Development Ltd | 00578111 | 20/09/2007 | Dissolved |
| R W Data Ltd | 00390244 | 20/09/2007 | Dissolved |
| Raynumber Ltd | 05294238 | 14/12/2004 | Dissolved |
| SPIRENT B.V. | FC024874 | 20/09/2007 | Dissolved |
| Shopleaf Ltd | 05290176 | 14/12/2004 | Dissolved |
| Shopridge Ltd | 05294232 | 14/12/2004 | Dissolved |
| Shopstamp Ltd | 05294176 | 14/12/2004 | Dissolved |
| Shoptree Ltd | 05294239 | 14/12/2004 | Dissolved |
| Spirent Financing (Cayman) Ltd | FC024337 | 24/01/2003 | Dissolved |
| Spirent Guernsey Ltd | FC023751 | 25/02/2002 | Dissolved |
| Telecom Analysis Systems Ltd | 01525139 | 20/09/2007 | Dissolved |
| Name | Company Number | Date Appointed | Date Resigned | Rating |
|---|---|---|---|---|
| ALBECK CONSULTING LTD | 02546003 | 04/10/1991 | 29/10/2003 | Dissolved |
| BOWTHORPE LIMITED | 03900841 | 06/05/2009 | 27/10/2014 | Not Trading |
| BOWTHORPE LIMITED | 03900841 | 20/09/2007 | 06/09/2016 | Not Trading |
| CAMBRIDGE ANALYTICAL GROUP LIMITED | 01908036 | 06/05/2009 | 27/10/2014 | Not Trading |
| CAMBRIDGE ANALYTICAL GROUP LIMITED | 01908036 | 20/09/2007 | 06/09/2016 | Not Trading |
| EARLYNOW LIMITED | 05084126 | 06/05/2009 | 27/10/2014 | Not Trading |
| EARLYNOW LIMITED | 05084126 | 29/11/2004 | 06/09/2016 | Not Trading |
| FLASKRANCH LIMITED | 05174936 | 29/11/2004 | 30/12/2004 | Dissolved |
| GROOVEMODEL LIMITED | 05268529 | 29/11/2004 | 14/03/2005 | Dissolved |
| HELICAL (CARDIFF) LIMITED | 05268782 | 29/11/2004 | 14/03/2005 | Dissolved |
| INCLEX NO 2 LIMITED | 06605875 | 14/09/2012 | 06/09/2016 | Dissolved |
| INCLEX NO 3 LIMITED | 04207632 | 06/05/2009 | 27/10/2014 | Not Trading |
| INCLEX NO 4 LIMITED | 02648579 | 06/05/2009 | 27/10/2014 | Dissolved |
| INCLEX NO 4 LIMITED | 02648579 | 20/09/2007 | 06/09/2016 | Dissolved |
| INCLEX NO 5 LIMITED | 03417067 | 06/05/2009 | 27/10/2014 | Not Trading |
| INCLEX NO 5 LIMITED | 03417067 | 20/09/2007 | 06/09/2016 | Not Trading |
| INCLEX NO 6 LIMITED | 04264467 | 06/05/2009 | 27/10/2014 | Not Trading |
| INCLEX NO 6 LIMITED | 04264467 | 03/08/2001 | 06/09/2016 | Not Trading |
| INCLEX NO 7 LIMITED | 02279804 | 06/05/2009 | 27/10/2014 | Not Trading |
| INCLEX NO 7 LIMITED | 02279804 | 05/09/2012 | 06/09/2016 | Not Trading |
| INCLEX NO 8 LIMITED | 01632114 | 06/05/2009 | 27/10/2014 | Dissolved |
| INCLEX NO 8 LIMITED | 01632114 | 20/09/2007 | 06/09/2016 | Dissolved |
| MATCHEARTH LIMITED | 05227759 | 14/12/2004 | 14/03/2005 | Dissolved |
| PAPERBRICK LIMITED | 05227748 | 14/12/2004 | 14/03/2005 | Dissolved |
| PG INTERNATIONAL LIMITED | 00688533 | 06/05/2009 | 27/10/2014 | Not Trading |
| PG INTERNATIONAL LIMITED | 00688533 | 20/09/2007 | 06/09/2016 | Not Trading |
| RATELAWN LIMITED | 05260657 | 29/11/2004 | 14/03/2005 | Dissolved |
| SHIPBRICK LIMITED | 05234102 | 06/05/2009 | 27/10/2014 | Not Trading |
| SHIPBRICK LIMITED | 05234102 | 29/11/2004 | 06/09/2016 | Not Trading |
| SHOPFILE LIMITED | 05279002 | 14/12/2004 | 14/03/2005 | Dissolved |
| SPIRENT (OVERSEAS) LIMITED | FC022560 | 10/07/2000 | 06/09/2016 | Silver |
| SPIRENT CAPITAL LIMITED | 03806529 | 06/05/2009 | 27/10/2014 | Not Trading |
| SPIRENT CAPITAL LIMITED | 03806529 | 13/07/1999 | 06/09/2016 | Not Trading |
| SPIRENT COMMUNICATIONS PLC | 00470893 | 01/02/2014 | 04/05/2016 | Silver |
| SPIRENT FINANCIAL LIMITED | 03806518 | 06/05/2009 | 27/10/2014 | Not Trading |
| SPIRENT FINANCIAL LIMITED | 03806518 | 13/07/1999 | 06/09/2016 | Not Trading |
| SPIRENT HOLDINGS LIMITED | 03451782 | 06/05/2009 | 27/10/2014 | Silver |
| SPIRENT HOLDINGS LIMITED | 03451782 | 20/09/2007 | 06/09/2016 | Silver |
| SPIRENT INVESTMENT LIMITED | 04118396 | 06/05/2009 | 27/10/2014 | Silver |
| SPIRENT INVESTMENT LIMITED | 04118396 | 28/11/2000 | 06/09/2016 | Silver |
| SPIRENT LIMITED | 00720989 | 06/05/2009 | 27/10/2014 | Not Trading |
| SPIRENT LIMITED | 00720989 | 20/09/2007 | 06/09/2016 | Not Trading |
| SPIRENT SHARESAVE TRUST LIMITED | 03430194 | 06/05/2009 | 27/10/2014 | Not Trading |
| SPIRENT SHARESAVE TRUST LIMITED | 03430194 | 13/11/1997 | 06/09/2016 | Not Trading |
| SPIRENT SYSTEMS LIMITED | 02638491 | 06/05/2009 | 27/10/2014 | Not Trading |
| SPIRENT SYSTEMS LIMITED | 02638491 | 20/09/2007 | 06/09/2016 | Not Trading |