| WAI TUNG SECOND MEDICAL LIMITED | | Live |
| SECOND UNITED LIMITED | Private company limited by shares | Dissolved |
| NEW AND SECOND WATCHES LIMITED | Private company limited by shares | Dissolved |
| Second Wave Limited | Private company limited by shares | Live |
| SECOND WIND COMPANY LIMITED | Private company limited by shares | Dissolved |
| Harbin Wind Second Investment Limited | Private company limited by shares | Live |
| SECOND WINGS LIMITED | Private company limited by shares | Dissolved |
| SECONDA LIMITED | Private company limited by shares | Live |
| WONG SHIU CHI SECONDARY SCHOOL | Company limited by guarantee | Live |
| SECONDAUGGHTEROMANCE Limited | | Live |
| Second-Brain Technology Limited | | Live |
| SECONDEARN DEVELOPMENT LIMITED | Private company limited by shares | Dissolved |
| SecondMarket Asia Limited | Private company limited by shares | Dissolved |
| SECONDMENT LIMITED | Private company limited by shares | Live |
| Secondnatvre Limited | | Live |
| SecondOfMay Limited | Private company limited by shares | Live |
| SECONDOOR LIMITED | Private company limited by shares | Dissolved |
| SECONDOPINION.COM LIMITED | Private company limited by shares | Dissolved |
| 5 SECONDS LIMITED | Private company limited by shares | Live |
| 3 Seconds Limited | | Live |
| THIRTY SECONDS FILM COMPANY LIMITED | Private company limited by shares | Live |
| Ten Seconds Digital Technology (HONGKONG) Co., Limited | Private company limited by shares | Live |
| LIGHT SECONDS TECHNOLOGY (INTERNATIONAL) LIMITED | Private company limited by shares | Live |
| Thirty Seconds Online Shopping Mall HK Limited | | Live |
| MINING SECONDS LIMITED | Private company limited by shares | Live |
| Counting Seconds Mobile Limited | Private company limited by shares | Live |
| NINE SECONDS NINE COMPANY LIMITED | | Live |
| HK SECONDS PAYING TECHNOLOGY CO., LIMITED | Private company limited by shares | Live |
| Three Seconds Trading Limited | Private company limited by shares | Live |
| Twenty Seconds Restaurant Limited | Private company limited by shares | Live |
| Twenty Seconds Workshop Limited | Private company limited by shares | Live |
| Five Seconds Worldwide Limited | Private company limited by shares | Live |
| SecondsGold Trading Limited | Private company limited by shares | Live |
| SECONDUS NOMINEES LIMITED | Private company limited by shares | Live |
| SECONDVIEW MARKET LIMITED | Private company limited by shares | Live |
| SECONEX COMPANY LIMITED | Private company limited by shares | Dissolved |
| SECONOM LIMITED | Private company limited by shares | Live |
| SECOPE TECHNOLOGY LIMITED | Private company limited by shares | Live |
| U.S. SECOR INTERNATIONAL LIMITED | Private company limited by shares | Dissolved |
| SECORE LIMITED | Private company limited by shares | Dissolved |
| SECOREN LIMITED | Private company limited by shares | Live |
| T & T SECORP LIMITED | Private company limited by shares | Live |
| SECORPINC HONG KONG LIMITED | Private company limited by shares | Dissolved |
| SECOSY INTERNATIONAL LIMITED | Private company limited by shares | Live |
| SECOTA & COMPANY LIMITED | Private company limited by shares | Live |
| SECOTEC LIMITED | Private company limited by shares | Live |
| SECOTRADE 61 PTY LIMITED | Private company limited by shares | Live |
| Secoya S&A Limited | Private company limited by shares | Live |