| 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 |
| SIGN-A-RAMA (CHINA) CO., LIMITED | Private company limited by shares | Dissolved |
| SIGNARE JEWELLERY LIMITED | Private company limited by shares | Live |
| SIGNART INVESTMENTS LIMITED | Private company limited by shares | Dissolved |
| TMF Signatories Limited | Private company limited by shares | Live |
| EAS Signatory Limited | Private company limited by shares | Live |
| KEY SIGNATURE COMPANY LIMITED | Private company limited by shares | Dissolved |
| SIGNATURE LIMITED | Private company limited by shares | Live |
| SIGNATURE COMPANY LIMITED -THE- | Private company limited by shares | Dissolved |
| SIGNATURE I & D LIMITED | Private company limited by shares | Dissolved |
| LC SIGNATURE LIMITED | Private company limited by shares | Dissolved |
| WAN SIGNATURE COMPANY LIMITED | Private company limited by shares | Live |
| D18 SIGNATURE LIMITED | Private company limited by shares | Live |
| V.T SIGNATURE LIMITED | Private company limited by shares | Live |
| V Signature Limited | Private company limited by shares | Live |
| NEW SIGNATURE LIMITED | Private company limited by shares | Live |
| Signature IP Limited | | Live |
| Queens Signature Co., Limited | Private company limited by shares | Live |
| SignaturePrint International Limited | Private company limited by shares | Live |
| DEER GARDEN SIGNATURES LIMITED | Private company limited by shares | Live |
| Signature-Search (HK) Limited | Private company limited by shares | Dissolved |
| Signax Limited | Private company limited by shares | Live |
| Signboard Paradise Limited | Private company limited by shares | Live |
| SignCharge Limited | Private company limited by shares | Live |
| SIGNCHECK LIMITED | Private company limited by shares | Live |
| SIGNCO LIMITED | Private company limited by shares | Live |
| SIGNCOMPLEX LIMITED | Private company limited by shares | Dissolved |
| SIGNCOMPLEX LIMITED | Private company limited by shares | Live |
| Hong Kong Signda Trade Limited | Private company limited by shares | Live |
| SIGNDREAM INTERNATIONAL INTEGRATED MARKETING COMMUNICATION CO., LIMITED | Private company limited by shares | Live |
| SIGN-E LIMITED | Private company limited by shares | Dissolved |
| Non Signe Limited | Private company limited by shares | Live |
| Signed Capital Limited | Private company limited by shares | Live |
| Signeo Venture Limited | Private company limited by shares | Live |
| SIGNER LIMITED | Private company limited by shares | Live |
| GOLD SIGNER LIMITED | Private company limited by shares | Dissolved |
| SIGNES LIMITED | Private company limited by shares | Dissolved |
| SIGNET COMPANY LIMITED | Private company limited by shares | Live |
| SIGNEX LIMITED | Private company limited by shares | Dissolved |
| SIGNFAST ENTERPRISES LIMITED | Private company limited by shares | Dissolved |
| SIGNFAST TECHNOLOGY (HONGKONG) CO., LIMITED | Private company limited by shares | Live |
| HONGKONG SIGNFORD CO., LIMITED | Private company limited by shares | Live |
| SIGNFOREE LIMITED | Private company limited by shares | Live |
| SIGNICORE HK LIMITED | Private company limited by shares | Live |
| 3 Significant Limited | Private company limited by shares | Live |
| SIGNIFICANT SIGN LIMITED | Private company limited by shares | Live |
| South Significant Perspective Limited | Private company limited by shares | Live |
| Signifig Limited | Private company limited by shares | Live |
| Signify Limited | Private company limited by shares | Live |
| Signify Entertainment Asia Limited | Private company limited by shares | Live |
| Signin Limited | Private company limited by shares | Live |
| SIGNIN TECHNOLOGY COMPANY LIMITED | Private company limited by shares | Live |
| Global Signing Co., Limited | Private company limited by shares | Live |
| SIGNING GOOD LAND & INVESTMENT LIMITED | Private company limited by shares | Live |
| SIGNITY HONG KONG LIMITED | Private company limited by shares | Live |
| SIGNIX LIMITED | Private company limited by shares | Live |
| SignLight Limited | Private company limited by shares | Live |