| Optec Co., Limited | Private company limited by shares | Live |
| OPTEC ELECTRONICS LIMITED | Private company limited by shares | Live |
| GIKEN OPTEC (ASIA) LIMITED | Private company limited by shares | Live Commenced dormancy on 21-Sep-2015 |
| GIKEN OPTEC HONG KONG LIMITED | Private company limited by shares | Live |
| OPTEC (HONG KONG) LIMITED | Private company limited by shares | Live |
| KOCENT OPTEC LIMITED | Private company limited by shares | Live |
| OPTEC TECHNOLOGY LIMITED | Private company limited by shares | Live |
| OPTECH LIMITED | Private company limited by shares | Dissolved |
| CHINTEK OPTECH LIMITED | Private company limited by shares | Live |
| Optech Co., Limited | Private company limited by shares | Live |
| OPTECH HEALTHCARE CO., LIMITED | Private company limited by shares | Dissolved |
| OPTECH ENTERPRISES LIMITED | Private company limited by shares | Dissolved |
| HK GENGMING OP-TECH COMPANY LIMITED | Private company limited by shares | Live |
| OP-TECH PHOENIX COMPANY LIMITED | Private company limited by shares | Dissolved |
| VARITRONIX OPTECH LIMITED | Private company limited by shares | Dissolved |
| WISE POWER OPTECH COMPANY LIMITED | Private company limited by shares | Live |
| OPTECK INTERNATIONAL LIMITED | Private company limited by shares | Dissolved |
| OPTECK MANUFACTURING GROUP LIMITED | Private company limited by shares | Live |
| OPTECS LIMITED | | Live |