O.F.D.M.,
Obwohl,
Occidental Publishing,
Octopussy,
Offtakt,
OI DA MO Records,
One Artist,
One Take One Hit Recods,
Operation 23,
Operation Phoenix Entertainment,
Optik Records,
Ostblokk Records,
Our Distribution,
Out 4 Fame Entertainment,
Outnow Records,
Overstolz
