| Company name | Reg. code |
|---|---|
| OZZERA OÜ | 17303176 |
| OZZA OÜ | 16281567 |
| OTTERA OÜ | 12661406 |
| OSPERA OÜ | 14450698 |
| OPERA OÜ | 12048756 |
| OMERA OÜ | 11320512 |
| OPZER OÜ | 16713529 |
| OLERA OÜ | 14469284 |
| ÖZERS OÜ | 17221923 |
| OLKERA EESTI OÜ | 12671461 |
| CABALLERA OPERA OÜ | 17003505 |
| OMERA TRADING OÜ | 17276031 |
| OPERA DESIGN OÜ | 11976750 |
| OPERA INVEST OÜ | 12620084 |
| NARGEN OPERA OÜ | 11109757 |
| OPERA RENAISSANCE OÜ kustutatud | 14646237 |
| OZERO HOLDING OÜ | 12774244 |
| MIZERA NETWORK SERVICES OÜ kustutatud | 12664343 |
| ÖVERA PUIT JA AED OÜ kustutatud | 11620349 |
| SERKAN OZER TECHNOLOGY OÜ kustutatud | 16166317 |
| TRIANQA OÜ kustutatud (former name CAFÉ OPERA OÜ) | 14841447 |