| Name | Company Number | Date Appointed | Rating |
|---|---|---|---|
| Awa 153 Ltd | 05518428 | 26/07/2005 | Dissolved |
| Awa 153 Ltd | 05518428 | 26/07/2005 | Dissolved |
| Bioinformatics Ltd | 01247941 | 18/10/1992 | Dissolved |
| D N A Probes Ltd | 01727829 | 14/10/1992 | Dissolved |
| International Medical Diagnostics Ltd | 01535653 | 14/10/1992 | Dissolved |
| L H Bioprocessing Ltd | 01765046 | 03/10/1993 | Dissolved |
| Molecular Biology Ltd | 01568792 | 18/10/1992 | Dissolved |
| Parthold Ltd | 00372085 | 14/10/1992 | Dissolved |
| Porton Capital Projects Ltd | 01895753 | 14/10/1992 | Dissolved |
| Porton Crawley Ltd | 01041879 | 14/10/1992 | Dissolved |
| Porton Developments Ltd | 01783826 | 14/10/1992 | Dissolved |
| Porton Research Ltd | 01800725 | 14/10/1992 | Dissolved |
| Speywood Communications Ltd | 01143723 | 18/10/1992 | Dissolved |
| The Speywood Laboratory Ltd | 01793168 | 14/10/1992 | Dissolved |
| alarbrook ltd | 01749065 | 14/10/1992 | Dissolved |
| Name | Company Number | Date Appointed | Date Resigned | Rating |
|---|---|---|---|---|
| COOMBE HILL HOLDINGS (1946) LIMITED | 00405949 | 08/11/2009 | 31/10/2010 | Gold |
| Courts Plc | 00272534 | 14/10/1999 | 31/12/2002 | Dissolved |
| IPSEN BIOPHARM LIMITED | 01653765 | 22/06/1991 | 14/12/2001 | Gold |
| IPSEN DEVELOPMENTS LIMITED | 03200696 | 15/11/2001 | 04/06/2004 | Gold |
| POTHOLD LIMITED | 01749071 | 14/10/1992 | 13/10/2000 | Not Trading |
| Porton Cambridge Ltd | 01680771 | 14/10/1992 | 12/05/1994 | Dissolved |
| SPECWOOD LIMITED | 01146287 | 14/10/1992 | 13/10/2000 | Not Trading |
| Speywood Holdings Ltd | 02952498 | 19/09/1994 | 12/12/1994 | Dissolved |
| Speywood Holdings Ltd | 02952498 | 19/09/1994 | 02/10/1996 | Dissolved |