| Company | Timeline | Status | |
| Aitken & Howard Demerara Limited Director • Timber Merchant | 9 Oct 1992←25 Years→14 Dec 2017 | Active | |
| Gilmour & Aitken, Limited Director • Timber Merchant | 30 Aug 1990←27 Years→14 Dec 2017 | Active | |
| Aitken & Stewart Limited Director • Timber Merchant | 25 Sep 1989←28 Years→14 Dec 2017 | Active | |
| Aitken & Howard Limited Director • Timber Merchant | 25 Sep 1989←28 Years→14 Dec 2017 | Active | |
