- NATIONAL IRANIAN GAS COMPANY (NIGC)
- NATIONAL IRANIAN PETROCHEMICAL COMPANY (NIPC)
- KALA NAFT TEHRAN
- PARS OIL AND GAS COMPANY (POGC)
- NATIONAL IRANIAN SOUTH OIL COMPANY (NISOC)
- IRANIAN OFFSHORE OIL COMPANY (IOOC)
- OIL INDUSTRIES ENGINEERING AND CONSTRUCTION (OIEC)
- RESEARCH INSTITUTE OF PETROLEUM INDUSTRY (RIPI)
- NIROO RESEARCH INSTITUTE (NRI)
- TARH O PALAYESH (TOP)
- HIRBODAN
- PARS OIL COMPANY (POC)
- Gachsaran Oil & Gas Production Company
- Karoon Oil&Gas Production Company
