?- Abu Dhabi National Oil Company
- Chevron Corporation
- China Petrochemical Corporation
- CNOOC Limited
- Eni SpA
- Evonik Industries AG
- Exxon Mobil Corporation
- Formosa Petrochemical Corporation
- Gazprom Neft PJSC
- GP Global
- GS Caltex Corporation
- Indian Oil Corporation Ltd
- LUKOIL
- NESTE
- Nynas AB
- Petrobras
- PETRONAS Lubricants International
- Philips 66 Company
- Repsol
- Saudi Arabian Oil Co.
- Sepahan Oil
- Shell Plc
- SK Lubricants Co. Ltd
- S-OIL CORPORATION
- Total Energies