Bedrift O - Slemdal
- Ollen AS
- Osloshippingadvisors AS
- Orion
- Owa AS
- Ortocon AS
- Orion
- Okav AS
- Obao AS
- Occw AS
- Oppenheim AS
- Oden AS
- Oliverlunden AS
- Omono AS
- Opengarden AS
- Olha Hramatina
- Olga Kocourkova
- Odin Teknikk AS
- Oslo Kfu
- Ok Invest
- Oslo Kfu
- Ortho-med ANS
- Oxy Multimedia ANS
- Ok Investments AS
- Opseth Optimize
- Olesol Holding AS
- Ortus Invest AS
- Oleksandr Peresolyak
- Ormetangen Holding AS
- Ormetangen Holding AS
- Orheim Polarviten
- Ohg-Revyen
- Opplandsgt 5 AS
- Omr Holding AS
- Oslo Alpine Sportsklubb
- Obron Midt AS Konkursbo
- Obron Midt AS Konkursbo
- Ohg-Revyen 2017
- Ohg-Revyen 2019
- Ohg-Revyen 2019
- Oda Kolbjørnsen-Tomassen
- Oftestad Eivor Andersen
- Os Business Consulting AS
- Oslo Gynekologiske Klinikk AS
- Opengarden Ingvild Huseby
- Othilie Eiendom i ANS
- Othilie Eiendom III ANS
- Othilie Eiendom II ANS
- Othilie Eiendom IV ANS
- Oslo Rotary Klubb
- Ole Andreas Wiese
- Oliver Gbabre Zohore Bergstedt
- Okta Service Tomasz Kukulski
- Oslo Vinskole Monica Wilhelmsen
- Otto Sverdrups vei 9 AS
- Oppigard Lervåg V/Lisbeth Røe Flobakk
- Ok Consulting Ola Knut Olsen
- Optimist Design Mette Halvorsen Fritsch
- Oslo Relocation Services Frederikke Gasmann-Brott
- Oversettelser Fransk Norsk/Norsk Fransk S Rustad
- Oslo Guidecompany the Original Oslo City Walks Liv Rygland