Bedrift O - Homansbyen
- Onkel AS
- OMG AS
- Orgservice AS
- Organisasjonsservice AS
- Olbios AS
- Oktra AS
- Odb AS
- Odeon AS
- Ogen AS
- Olsen
- Okkult AS -
- Omnia AS
- Oticon AS
- Outsourcia AS
- Oak
- Olicem
- Olicem
- Oslomet Podcastforening
- Orv 38 AS
- Oslo Hudlegeklinikk AS
- Onkel Estrup
- Oslomet Podcastforening
- Odin Bidco AS
- Oslo Symfoniorkester
- ODEON Kino
- OsloMet - Storbyuniversitetet
- Olsen Monica
- Oslomet Gaming
- Oculus Capital AS
- Oslomet Il
- Oslomet Lacrosse
- Oda Landewall
- Oppegårdveien Holding AS
- Ole Tørklep AS
- Oryx Invest AS
- Oslo Barneklinikk AS
- Oak Tree AS
- Oda Landewall AS
- Ofo Invest AS
- Olga Cassidy
- Omundsen Terje
- Oppegårdveien 2 AS
- Oslo Boligutvikling AS
- Okkenhaug Prosjekt
- Olio Mipco AS
- Odd Cocktailbar
- Okkult Coco AS
- Okkult Holding AS
- O19g Q AS
- Olio Holding AS
- Oslo Grammofon DA
- Olena Khodakivska
- Oslo Skredderstue
- Odd 8 AS
- Odd Coctailbar AS
- Oda Tømte
- Oslo Arkitektforening
- Opera Forlag
- Omar Savan
- Oslo Studio
- Oris Dental AS
- Oslo Laserklinikk AS
- Oslo Hudklinikk
- Oslo Hudlegekontor AS
- Oslo Dermatology AS
- Oslo Eiendomssenter AS
- Ovesen Film
- Olesandr Volynskyi
- Oslo Dermatology AS
- Olaussengården Tomt AS
- Ove Brevik AS
- Odd Lunde AS
- Ourway Tours AB
- Opm-Op AS
- Olivia Hegdehaugsveien
- Omhu Bemanning AS
- Opplysningsrådet for Veitrafikken AS
- Ow Utsira nord AS
- Oslo Light Industries AS
- Onelog Regnbueveien 9 AS
- Oslo Hudlegesenter AS Fq
- Ole Kristian Kleivenes
- Oej 370 Holding AS
- Offentlig Bygg Furuset AS
- Oslo Science Hub AS
- Oscars gate 35 AS
- Oslo Family Office AS
- Ola Harder Fredriksen
- Oscar Lokalmedisinske Senter
- Oscars gate 54
- Oslo Nummer Pinpin
- Oily By Cherdsri
- Objective Maziar Ghahramani
- Oj Wiig Media
- Oslo City Olio -
- Othelie S. Brødholt
- Ougendalv Charlotte Ougendal
- Olsen Ken Ole
- Oslo Community Theatre
- Oslo Community Theatre
- Ocb Media AS Tvangsavviklingsbo
- Ocb Media AS Tvangsavviklingsbo
- Oslo 3D Laserskanning AS
- Oslo International Club
- Oslo Odontologisk Søvnklinikk AS
- Oslo International Angels
- Oslo vest Apartment AS
- Oslo Helse Legevakt
- Oslo Korean School
- Oscars gate 30 AS
- Oscar Jacobson Hegdehaugsveien
- Oslo International Hub AS
- Omhu Bemanning AS Hovednummer
- Oris Dental Homansbyen
- Onelog Norway Vestby Holding AS
- Onelog Norway Torvstikkeren 10 AS
- Oslometodiske & Funkdidaktiske Ensemble
- Oslometodiske & Funkdidaktiske Ensemble
- Onnec Sweden Norway Filial
- Oslomet - Storbyuniversitetet Studiested Pilestredet
- Onnec Sweden Norway Filial
- Ole Petter Haugen Consulting
- Oscars gate 35 Holding AS
- Oscars gate 53-55 AS
- Orange Spa Wiparut Nilapaka
- Ocb Ole Christian Bøe
- Oslo Service Attaches Association
- Olsen Skytetrening & Foredrag
- Oslo Hudklinikk Hudlege Bjerke
- Oscars gate 30 Eiendom AS
- Or Not To Be AS
- Oslo Bo Invest 1 AS
- Opsund Frisør Siri Opsund
- Onelog Norway Regnbueveien 9 Holding AS
- Onelog Norway Torvstikkeren 10 Holding AS
- Oslogruppen Av Antroposofisk Selskap i Norge
- Omsorgsboliger - Boliger for Eldre og Funksjonshemmede Welhavens gate Boliger