Ophidian

unknown

Opio Media

unknown

Opium Eyes Records

unknown

OPOS Records

unknown

ÖppåHåppa Records

unknown

Opposite Productions

unknown

Oppressed Records

unknown

Optical Sound

France

Optimo Singles Club

unknown

Optimus Discos

unknown

Opus

unknown

Opus 3 Records

Sweden

Oraculo Records

Spain

Orange Music

unknown

Orange Recordings

Canada

Orange Records

unknown

Orange Twin Records

unknown

Oranje Records

unknown

Orbeat Music

Brazil

Orbison Records

unknown

Orbital Productions

unknown

Orchard

unknown

Orchid Tapes

unknown

Orden Productions

unknown

Oreade Music

unknown

Orfeo (ARG)

Argentina

Orfeo (URU)

Uruguay

Orfeu

Portugal

ORG Music

USA

Org Records

unknown

Orgone Toilet

unknown

Origami Records

USA

Original Master Series

unknown

Original Signal Recordings

USA

Original Sound Entertainment

unknown

Origo Sound

Norway

Ork Records

unknown

Orleans

unknown

Orphanage Records

unknown

Orpheus Records

unknown

Orphic

unknown

Os Filhos Do Rock

Portugal

OS Music

unknown

Oscar Records

Poland

OSCL

Australia

Osk Records

unknown

Oskar

Poland

Otdelenie Vykhod

unknown

OTF Records

USA

Other Music Recording Co.

unknown

Other Peoples Music

unknown

Other Tongues

unknown

Other Voices Records

unknown

Otorecords

unknown

Ottersong

unknown

Our Choice

unknown

Our Future Records

unknown

Our Own Records

unknown

Our Quinnessential Music Group

unknown

Our Record Company

unknown

Our Rekords

unknown

Our Soil, Our Strength

unknown

Our World Records

unknown

Out Of Darkness Records

unknown

Out Of Line

Germany

Out Of Town Records

unknown

Out Of Tune Records

unknown

Outcast Records

unknown

Outer Battery Records

USA

Outer Galaxie Publishers

unknown

Outer Himalayan Records

unknown

Outer Limits

unknown

Outer Music

unknown

Outer Universe Research Records

unknown

Outfall Records

unknown

Outlaw Label

unknown

Outlaw Recordings

unknown

Outlaws Fan-Club

unknown

Outlier

unknown

Outline Records

unknown

Outlook Music

USA

Outpost Recordings

unknown

Outshined Records

unknown

Outside Inside Records

unknown

Outside Music

unknown

Outside Records

France

Outsider Records

USA

Outvillage Records

unknown

Ovação

Portugal

Over And Out

unknown

Over Under Through

unknown

Overa Negra

unknown

Overcat

France

Overcoat

unknown

Overcome Records

unknown

Overdose On Records

USA

Overdrive

unknown

Overground Records

United-Kingdom

OverHead Music

unknown

Overhead Records

unknown