| Byrn Limited | Private company limited by shares | Live |
| BYRNE COMPUTING LIMITED | Private company limited by shares | Dissolved |
| BYRNE AND HICKMAN LIMITED | Private company limited by shares | Live |
| JACKSON BYRNE LIMITED | Private company limited by shares | Dissolved |
| JOHN BYRNE ASSOCIATES LIMITED | Private company limited by shares | Dissolved |
| Byrne Oilfield Solutions Limited | Private company limited by shares | Live |
| Qiao Byrne International Company Limited | | Live |
| Byrne International Trading Limited | Private company limited by shares | Live |
| BYRNECO LIMITED | Private company limited by shares | Live Ceased dormancy on 21-Jun-1999 |
| Byrne-Kwok Limited | Private company limited by shares | Live |
| BYRNES INTERNATIONAL LIMITED | Private company limited by shares | Dissolved |