- OIRAC Invest AG in Liquidation
- Dorfstrasse 38
- Baar
- ZG
- OILPRO SA
- Baarerstrasse 79
- Zug
- ZG
- OIB Oehen Informatik & Beratung
- Bachtalen 6
- Hagendorn
- ZG
- Oicos Holding AG in Liquidation
- Gartenstrasse 2
- Zug
- ZG
- Oil Production and Trade OPT SA
- Gewerbestrasse 5
- Cham
- ZG
- OilEnergy AG in Liquidation
- Metallstrasse 9A
- Zug
- ZG
- Oilfield Investments Limited AG
- Untermüli 9
- Zug
- ZG
- OIS-Group 1 GmbH
- Sonneggstrasse 10
- Cham
- ZG
- Oiltube Trading GmbH in Liquidation
- Gartenstrasse 4
- Zug
- ZG
- Oilway SA in Liquidation
- Baarerstrasse 1
- Zug
- ZG
- Oiltex AG in Liquidation
- Bahnhofstrasse 12
- Zug
- ZG
- Oil & Gas Trading Company (OGTC) GmbH in Liquidation
- Gubelstrasse 15
- Zug
- ZG
- Oil Field Services Innovation AG in Liquidation
- Grabenstrasse 25
- Baar
- ZG
- Oil Exploit Holding AG in Liquidation
- Industriestrasse 22
- Zug
- ZG
- Oikos SA in Liquidation
- Bahnhofstrasse 10
- Zug
- ZG
- Oilshale Technology Holding AG in Liquidation
- Gotthardstrasse 20
- Zug
- ZG
- Oiltrade & Shipping BC Ltd in Liquidation
- Gewerbestrasse 5
- Cham
- ZG
- Oilis Holding Ltd.
- Baarerstrasse 101
- Zug
- ZG
- Oil and Energy Recruitment GmbH in Liquidation
- Lindenstrasse 8
- Baar
- ZG
- oiraler AG in Liquidation
- Lindenstrasse 16
- Baar
- ZG
- OIG OroImmo Group Sagl
- Baarerstrasse 82
- Zug
- ZG
- oicoss, Theochari
- Brunnmatt 14
- Cham
- ZG
- OiLBiNDER U-W-E AG
- Oberdorfstrasse 1
- Baar
- ZG
- Oikos Management SA
- Untermüli 6
- Zug
- ZG
- OISTE BIO GmbH
- Oberneuhofstrasse 5
- Baar
- ZG
- OINIO AG
- Baarerstrasse 37
- Zug
- ZG