| ORTISA LIMITED | Private company limited by shares | Dissolved |
| ORTM Capital Management Limited | Private company limited by shares | Live |
| ORTO LIMITED | | Live |
| ORTO INDUSTRIES CO. LIMITED | Private company limited by shares | Live |
| ORTOFON LIMITED | Private company limited by shares | Dissolved |
| ORTOLAN COMPANY LIMITED | Private company limited by shares | Dissolved |
| ORTOLUX LIMITED | Private company limited by shares | Live |
| ORTON LIMITED | Private company limited by shares | Dissolved |
| ORTON COMPANY LIMITED | Private company limited by shares | Dissolved |
| ORTONA COMPANY LIMITED | Private company limited by shares | Dissolved |
| HONGKONG ORT-PAN-CHINA MACHINERY INCORPORATION LIMITED | Private company limited by shares | Live |
| ORTRAK HOLDING COMPANY LIMITED | Private company limited by shares | Dissolved |
| ORTRAK TRADING COMPANY LIMITED | Private company limited by shares | Dissolved |
| ORTRE LIMITED | Private company limited by shares | Live |
| HONGKONG ORTRONICS INDUSTRY LIMITED | Private company limited by shares | Live |
| ORTSMESSE CO., LIMITED | Private company limited by shares | Live |
| EASTERN ORTUNE LIMITED | Private company limited by shares | Dissolved |
| Solis Ortus Limited | Private company limited by shares | Live |
| ORTUS SOLUTIONS LIMITED | Private company limited by shares | Live |
| ORTUS-T CO., LIMITED | Private company limited by shares | Live |