| Opencom (Hong Kong) Share Investment Limited | Private company limited by shares | Dissolved |
| OPENCONNECT SYSTEMS HONG KONG, LIMITED | Private company limited by shares | Dissolved |
| Opencons Limited | | Live |
| OPENCORP LIMITED | Private company limited by shares | Live |
| OpenDataBIM Limited | | Live |
| OPENDAY INVESTMENTS LIMITED | Private company limited by shares | Dissolved |
| OpenDeedigital Limited | | Live |
| OpenDoor Limited | Private company limited by shares | Dissolved |
| OpenDoor Co., Limited | Private company limited by shares | Live |
| OPENDOOR IMMIGRATION & EDUCATION LIMITED | Private company limited by shares | Dissolved |
| OpenE Technologies (HK) Limited | | Live |
| OPENECO LIMITED | Private company limited by shares | Live |
| OPENED SPACE HK LIMITED | Private company limited by shares | Live |
| openeight Limited | Private company limited by shares | Live |
| DREAM OPENER COMPANY LIMITED | Private company limited by shares | Live |
| Tech Opener Limited | Private company limited by shares | Live |
| OPENESHOP.COM NETWORKS LIMITED | Private company limited by shares | Dissolved |
| OPENEX TECHNOLOGIES LIMITED | Private company limited by shares | Live |
| OPENEX TECHNOLOGY LIMITED | | Live |
| OPENEX MECHANICAL TECHNOLOGY LIMITED | Private company limited by shares | Live |
| OpenExchange APAC Limited | Private company limited by shares | Live |
| OPENEXTS LIMITED | Private company limited by shares | Live |
| OpenF Technology Limited | | Live |
| OPENFIELD LIMITED | Private company limited by shares | Live |
| OpenFlow Limited | | Live |
| OPENFLOW INDUSTRIAL LIMITED | Private company limited by shares | Dissolved |
| OPENFORTUNE LIMITED | Private company limited by shares | Dissolved |
| OPENFOUND INVESTMENTS LIMITED | Private company limited by shares | Dissolved |
| OPENGAIN INVESTMENTS LIMITED | Private company limited by shares | Live |
| OpenGMV HK Limited | | Live |
| OPENGRAND LIMITED | Private company limited by shares | Dissolved |
| OPENGROUND LIMITED | Private company limited by shares | Live |
| Opengroup Charities Fundation Limited | Company limited by guarantee | Live |
| Openguys Marketing Limited | | Live |
| OPENHAAUS LIMITED | Private company limited by shares | Live |
| OPENHEART INVESTMENTS LIMITED | Private company limited by shares | Dissolved |
| Openhotelier Limited | Private company limited by shares | Live |
| OpenHR HK Limited | Private company limited by shares | Live |
| OPENHUNT LIMITED | Private company limited by shares | Live |
| OPENIC COMPANY LIMITED | Private company limited by shares | Live |
| OPENICE LIMITED | Private company limited by shares | Live |
| OPENIDEX COMPANY LIMITED | Private company limited by shares | Dissolved |
| OpenIM Corporation Limited | | Live |
| OPENINFO LIMITED | Private company limited by shares | Dissolved |
| Grand Opening Limited | Private company limited by shares | Live |
| GRAND OPENING TRADING COMPANY LIMITED | Private company limited by shares | Dissolved |
| OPENIT SYSTEMS LIMITED | Private company limited by shares | Dissolved |
| Openiva Trade Limited | | Live |
| OPENJAMB SYSTEMS LIMITED | Private company limited by shares | Dissolved |
| Openjob Limited | Private company limited by shares | Live |
| OPENKING COMPANY LIMITED | Private company limited by shares | Dissolved |
| OPENLAB LIMITED | Private company limited by shares | Dissolved |
| OPENLABS LIMITED | Private company limited by shares | Dissolved |
| Openlcdh Co., Limited | | Live |
| OpenLibrary Limited | Private company limited by shares | Live |
| OPENLIGHT LIMITED | Private company limited by shares | Live |
| OPENLINK COMPANY LIMITED | Private company limited by shares | Dissolved |
| OPENLINK HOLDINGS LIMITED | Private company limited by shares | Live |
| OPENLINK INTERNATIONAL INDUSTRIAL LIMITED | Private company limited by shares | Live |
| OpenLink Management Limited | Private company limited by shares | Dissolved |
| Openlist Limited | Private company limited by shares | Live |
| Openload Limited | Private company limited by shares | Dissolved |
| Openlot Technology Holding Limited | Private company limited by shares | Dissolved |
| OPEN-M TECHNOLOGY LIMITED | Private company limited by shares | Live |
| OpenMarket Saas solution Limited | Private company limited by shares | Live |
| OpenMind Hub Limited | Private company limited by shares | Live |
| OPENMIND MEGACORP ASIA LIMITED | Private company limited by shares | Live |
| OPENMIND CONSULTANT LIMITED | Private company limited by shares | Dissolved |
| OpenMind Group Limited | | Live |
| OpenMind International Limited | Private company limited by shares | Dissolved |
| OPENMIND INTERNATIONAL CORPORATION LIMITED | Private company limited by shares | Dissolved |
| Openmind International (Hong Kong) Limited | Private company limited by shares | Live |
| OPENMIND COMMERCIAL SERVICES COMPANY LIMITED | Private company limited by shares | Live |
| Openmind Commercial Services Consultants Limited | | Live |
| OPENMINE LIMITED | Private company limited by shares | Dissolved |
| OPENMINE LIMITED | Private company limited by shares | Live |
| Openmonet Limited | Private company limited by shares | Live |
| OPENMPF LIMITED | Private company limited by shares | Live |
| OPENNESS LIMITED | Private company limited by shares | Live |
| CLEVER OPENNESS LIMITED | Private company limited by shares | Live |
| OPENNESS BUSINESS CO., LIMITED | | Live |
| OpennFx Co., Limited | Private company limited by shares | Live |
| OPENOFFERING LIMITED | Private company limited by shares | Dissolved |
| OPENOFFERING (GREATER CHINA) LIMITED | Private company limited by shares | Dissolved |
| OPENOPEN GROUP HOLDINGS LIMITED | Private company limited by shares | Live |
| OpenPage Limited | Private company limited by shares | Live |
| OPENPARK.COM LIMITED | Private company limited by shares | Dissolved |
| OPENPAY LIMITED | Private company limited by shares | Live |
| OPENPEOPLE COMPANY LIMITED | Private company limited by shares | Dissolved |
| OPENPORT LIMITED | Private company limited by shares | Live |
| OPENPORT HONG KONG LIMITED | Private company limited by shares | Live |
| OPENPORT INTERNATIONAL TRADE LIMITED | Private company limited by shares | Dissolved |
| OpenQpon Limited | Private company limited by shares | Dissolved |
| OPENQUICKLY GROUP LIMITED | Private company limited by shares | Dissolved |
| openrestaurant Limited | Private company limited by shares | Live |
| OpenResty Limited | Private company limited by shares | Live |
| Openrice Limited | Private company limited by shares | Live |
| OpenRich Technology Co, Limited | Private company limited by shares | Live |
| OPENROAD APPRAISALS LIMITED | Private company limited by shares | Dissolved |
| OPENROAD CAPITAL LIMITED | Private company limited by shares | Dissolved |