| Company | Timeline | Status | |
| Johnston Excavators Ltd Director • Director | 19 Oct 2018←7 Years→Current | Active | |
| Johnston Tractors Limited Director • Agricultural Engineer | 24 Nov 2011←13 Years→Current | Active | |
| Tractors Limited Director • Agricultural Engineer | 22 May 2003←22 Years→Current | Active | |
| Agrigroup Limited Director • Director | 6 Dec 1995←29 Years→Current | Active | |
| Agrigroup Limited Secretary • Director | 6 Dec 1995←6 Years→25 Sep 2002 | Active | |
| Frank Johnston (Tractors) Limited Director • Agricultural Engineer | 20 Sep 1991←34 Years→Current | Active | |
