- BP p.l.c.
- Chevron USA Inc.
- China Petroleum & Chemical Corporation (Sinopec)
- Exxon Mobil Corporation
- Fuchs
- Gazprom Neft PJSC
- Gulf Oil Corporation Limited
- Idemitsu Kosan Co. Ltd
- Indian Oil Corporation Ltd
- JX Nippon Oil & Energy Corporation
- LUKOIL
- Quepet Lubricants
- Royal Dutch Shell PLC
- Total