Firma O - Fetsund
- Omari
- Ottesen & Co AS
- Okl Holding AS
- Olger Ropi
- Oksana Løwensprung
- Omlb Invest AS
- On Tools AS
- Olai Solheim AS
- Olsson Christian
- Odd Moen
- Oslo Montasje AS
- Ola Krokan
- Osvaldas Simonaitis
- Oro Kula
- Ola Thorud
- Ole-Petter Lomsnes
- Ole Albert Guttersrud
- Octavian Ceban Bygg
- Oslo Bil Auto AS
- Oslo Dog Runner AS
- Orgelkomiteen I Fet
- Odne Holm Wch
- Ove Andre Johansen
- Ole Patrick Scantlebury
- Oversetter Solveig Skartsæterhagen
- Ole Wilhelm Guttersrud
- Oslo Vb Bygg AS
- Orgelkomiteen I Fet
- Ole Rikard Haavet
- Ok Transport Olegs Kilups
- Olberg Bård Klova Skog
- Oscar Eide Haus Produksjon
- Oslo & Akershus Multi Service Grupp Jorge Vaca Mendez