Bedrift O - Holmenkollen
- Oppdrift AS
- Olausgården AS
- Oppkuven AS
- Otherwords AS
- Ozlow AS
- Opqm AS
- Oleimset AS
- Origination AS
- Oncoselect AS
- Optimuspistor AS
- Oslohandcenter AS
- Oralkirurgi AS
- Oribis AS
- Ovt AS
- Organisasjonspsykologisk Bistand
- Omar Malik
- Oslo Utviklingsselskap AS
- Optima Gruppen AS
- Orc Energy AS
- Osalg Saleem
- Olsonheimen Skog
- Oslo montessoriskole
- Oslo Walking AS
- Oslo Walking AS
- Optikus Holding AS
- Oslo montessoriskole
- Oled Holding AS
- Orbit Invest AS
- Option Invest AS
- Opptur Holding AS
- Oleanna Invest AS
- Omaha Invest AS
- Oslo Stupeklubb
- Oleksandr Orlychenko
- Olav Berge
- Oslo Stupeklubb
- Opuscapita Solutions AS
- Ondrej Nentwich
- Orca Maritime AS
- Oxit-Holding AS
- Osnes Assistanse
- Odd Mørk
- Opheim Holding AS
- Osc Holding AS
- Osc Eiendom AS
- Overskudd Invest AS
- Opis Invest AS
- Olma Holding AS
- Otber Consulting AS
- O13 Eiendom AS
- Onauma Fagersand
- Opsahl - Kunnskapsformidling
- Ohl Låhne
- Owe Iktkvalitet
- Ojt Holding AS
- Ojt Eiendom AS
- Oslo Eiendomsutleie AS
- Orchard Holding AS
- Oxhain Investments AS
- Oslo Sommerpark
- Omb Capital AS
- Ole Kristian Langdahl
- Ole Gulbrandsen Industridesign AS
- Oherrada Berg Consulting
- Oslo Montessoriskole Foreldrearbeidsutvalg
- Oslo Montessoriskoles Venneforening
- Oslomarka Forlag Skaiå
- Ole-Kristian Krukhaug
- Ola Krohn-Fagervoll
- Olav Morten Kise
- Olsson Komplett Eiendom
- One Two Invest AS
- Olav Aukrustsvei Bofellesskap
- Olsen Lisbeth Wiberg
- Olav Ingstadsvei 3 AS
- Olav Ingstadsvei 1 AS
- Ole Henrik Låhne
- Oca Equity Partners AS
- Ofelia Collado Cabataje
- Ole Messelt Drangsholt
- Origami Emiko Holta
- Omsorgshjelpen Mette Vikanes
- Ole Edvard Antonsen
- Oslovett Steinar Kjærnsrød
- Onkel Tomm's Hytte AS
- Omega Management V Sandvik
- Organisasjonen Bedre Veier (Obv)
- Ole Fredrik Anker-Rasch
- Ole Marius Tufto-Antonsen
- Olivieri Ma Soledad Alquizar
- Oslo Alligators Soft- og Baseballklubb
- Oslo Alligators Soft- og Baseballklubb
- Oslo Dekor V/ Siri Meltvedt Edvardsen
- Oslo Coffee Consulting Odd-Steinar Tøllefsen
- Oslo Relocation Services Frederikke Gasmann-Brott
- O O og Gustav B Bulls Legat