| Company | Timeline | Status | |
| Tinnitus And Hyperacusis Network Ltd Director • Director | 13 Jun 2019←5 Years→18 Jun 2024 | Dissolved | |
Holt Audiological Services Limited Director • Clinical Scientist | 9 Nov 2017←1 Year 5 Months→16 Apr 2019 | Dissolved | |
Holt Audiological Ltd Director • Director | 2 Feb 2015←2 Years 5 Months→11 Jul 2017 | Dissolved | |
| Holt Hearing And Balance Services Limited Director • Director | 11 Apr 2012←13 Years→Current | Active | |
| British Academy Of Audiology Director • Consultant Clinical Scientist | 1 Dec 2005←5 Years→10 Nov 2011 | Active | |
