| R & J WILLIAMS (KENT) LIMITED | Other manufacturing | 1950 | Total exemption (full) |
| HAMILTON LABORATORY GLASS LIMITED | Other manufacturing | 1973 | Total exemption (full) |
| HORNBY INDUSTRIES LIMITED | Other manufacturing | 1980 | Total exemption (full) |
| HORNBY LIMITED | Other manufacturing | 1981 | Group accounts |
| TV ONE LIMITED | Computers, electronics and optics | 1985 | Full accounts |
| HORNBY HOBBIES LIMITED | Other manufacturing | 1986 | Full accounts |
| HELLINGS FABRICATIONS LIMITED | Fabricated metal products | 1989 | Total exemption (full) |
| CELSIS LIMITED | Chemicals | 1992 | Full accounts |
| A L K S LIMITED | Fabricated metal products | 2002 | Total exemption (full) |
| EAST KENT COATINGS LIMITED | Fabricated metal products | 2004 | Total exemption (full) |
| ROE TIMBER FRAME LIMITED | Wood products | 2005 | Full accounts |
| B & D ENGINEERING LIMITED | Fabricated metal products | 2005 | Total exemption (full) |
| OCEAN SIGNAL LIMITED | Computers, electronics and optics | 2008 | Full accounts |
| WATERJET SIGNS LIMITED | Fabricated metal products | 2009 | Total exemption (full) |
| CELSIS GROUP LIMITED | Chemicals | 2010 | Full accounts |