| SIGNAL SUCCESS COMPANY LIMITED | Private company limited by shares | Dissolved |
| SURE SIGNAL COMPANY LIMITED | Private company limited by shares | Dissolved |
| SIGNAL SYSTEMS COMPANY LIMITED | Private company limited by shares | Dissolved |
| SIGNAL TECH ASIA LIMITED | Private company limited by shares | Dissolved |
| SIGNAL TECHNOLOGIES COMPANY LIMITED | Private company limited by shares | Live |
| SIGNAL TECHNOLOGY LIMITED | Private company limited by shares | Live |
| Signal Egg Technology Limited | | Live |
| Signal Technology Holding Consultancy Limited | Private company limited by shares | Live |
| SIGNAL THREE LIMITED | Private company limited by shares | Dissolved |
| SIGNAL THREE LIMITED | Private company limited by shares | Live |
| TIME SIGNAL LIMITED | Private company limited by shares | Dissolved |
| HK SIGNAL TRADE LIMITED | Private company limited by shares | Live |
| RICH SIGNAL TRADING LIMITED | Private company limited by shares | Dissolved |
| TUNE SIGNAL COMPANY LIMITED | Private company limited by shares | Dissolved |
| United Signal Limited | Private company limited by shares | Live |
| WANY SIGNAL LIMITED | Private company limited by shares | Dissolved |
| WELL SIGNAL LIMITED | Private company limited by shares | Dissolved |
| WELL CHANGE SIGNAL LIMITED | Private company limited by shares | Dissolved |
| WELL SIGNAL INVESTMENTS LIMITED | Private company limited by shares | Dissolved |
| WISE SIGNAL LIMITED | Private company limited by shares | Live |
| SIGNAL WISE LIMITED | Private company limited by shares | Dissolved |
| WITLONG SIGNAL LIMITED | Private company limited by shares | Dissolved |
| YOUNG SIGNAL COMPANY LIMITED | Private company limited by shares | Live |
| SignalBio Limited | Private company limited by shares | Live |
| SIGNALCON LIMITED | Private company limited by shares | Dissolved |
| SIGNALING LIMITED | Private company limited by shares | Live |
| ADVANCED SIGNALING COMPANY LIMITED | Private company limited by shares | Dissolved |
| SIGNALINKS LIMITED | Private company limited by shares | Live |
| SIGNALINKS TECHNOLOGY LIMITED | Private company limited by shares | Live |
| Signalint Limited | Private company limited by shares | Live |
| TRANSPORT SIGNALLING LIMITED | Private company limited by shares | Dissolved |
| SIGNALPLUS HK Limited | | Live |
| COMPUTEC SIGNALS LIMITED | Private company limited by shares | Live |
| Deep Signals Limited | Private company limited by shares | Live |
| Eleven Signals Technology Limited | Private company limited by shares | Live |
| 21 SIGNALS INTERNATIONAL LIMITED | Private company limited by shares | Dissolved |
| SAKSHAM TRANSPORT SIGNALS PRIVATE LIMITED | Private company limited by shares | Live |
| SHARP SIGNALS ASSET MANAGEMENT CO., LIMITED | Private company limited by shares | Live |
| Signals Technologies Limited | | Live |
| TRITRONIC SIGNALS LIMITED | Private company limited by shares | Live |
| ULTIMATE SIGNALS LIMITED | Private company limited by shares | Dissolved |
| WINNING SIGNALS LIMITED | Private company limited by shares | Dissolved |
| Signal.Sourcing Limited | Private company limited by shares | Live |
| SIGNAL-TECH LIMITED | Private company limited by shares | Dissolved |
| MCKIM SIGNALVISION GLOBAL CO., LIMITED | Private company limited by shares | Live |
| Signalytics Limited | Private company limited by shares | Live |