| Company | Timeline | Status | |
| John Alderson & Son Limited Director • Thermal Insulation Engineer | 30 Apr 1991←28 Years→15 Jul 2019 | Active | |
| John Alderson & Son Limited Secretary • Unreported | 30 Apr 1991←28 Years→15 Jul 2019 | Active | |
| Harefield Hall Hotel Limited Director • Thermal Insulation Engineer | 6 Apr 1991←28 Years→15 Jul 2019 | Active | |
