| Link | Location |
|---|
| Sean Ong | Singapore, Singapore |
| Wei Yang Gilbert Ong | Singapore, Singapore |
| Zhe Ming Ong | Singapore, Singapore |
| Nadezhda Onishchuk | Москва, Russia |
| Toshihiro Ono | Tokyo, Japan |
| Glenn Onos | Matthews, North Carolina, United States |
| Ronald Oomen | Deventer, Netherlands |
| Martijn Oost | Brussels, Belgium |
| Erik Oosterhuis | Bergschenhoek, Netherlands |
| Frey Oosterlinck | Harelbeke, Belgium |
| Albert Oosthuizen | Johannesburg, South Africa |
| Piotr Opalacz | Kraków, Poland |
| Pavel Oparin | Almaty, Kazakhstan |
| Yulia Openysheva | Moscow online, Russia |
| Douglas Opfer | Houston, Texas, United States |
