O
| OAR Consulting AG |
| Oceanica AG |
| Odeon Film AG |
| OFL – Anlagenleasing AG |
| OHB Technology AG |
| Oldenburgische Landesbank AG |
| OnVista AG |
| Oppermann Versand AG |
| Orbis AG |
| Otto Stumpf AG |
| OVB Holding AG |
| OAR Consulting AG |
| Oceanica AG |
| Odeon Film AG |
| OFL – Anlagenleasing AG |
| OHB Technology AG |
| Oldenburgische Landesbank AG |
| OnVista AG |
| Oppermann Versand AG |
| Orbis AG |
| Otto Stumpf AG |
| OVB Holding AG |