| ADMA-OPCO | Abu Dhabi Marine Operating Company |
| ADNOC | Abu Dhabi National Oil Company |
| ADOC | Abu Dhabi Oil Company |
| Agip | Agip SpA |
| Agoco | Arabian Gulf Oil Company (Libya) |
| Amerada Hess | Amerada Hess Corporation |
| AOC | Arabian Oil Company |
| Aquitaine | Aquitane Societe Nationale des Petroles d’Aquitaine |
| Aramco | Saudi Arabian Oil Company (Saudi Aramco) |
| Arco | Atlantic Richfield Company |
| Asamera | Asamera Oil |
| Ashland | Ashland Oil |
| BP | BP plc |
| Brega Marketing | Brega Petroleum Marketing Company |
| Buttes | Buttes Gas & Oil Company |
| Calasiatic | Calasiatic Petroleum Company |
| Caltex (PT) | PT Caltex Pacific Indonesia |
| ChevronTexaco | ChevronTexaco Corporation |
| Conoco | Continental Oil Company |
| Corpoven | Corpoven SA |
| DPC | Dubai Petroleum Company |
| EGPC | Egyptian General Petroleum Corporation |
| ENI | ENI |
| ENOC | Emirates National Oil Company (UAE) |
| Equinor | Equinor |
| ExxonMobil | ExxonMobil Corporation |
| GASCO | Abu Dhabi Onshore Gas Company |
| Getty | Getty Oil Corporation |
| GOC | Gabon Oil Company |
| Gulf | Gulf Oil Corporation |
| Hispanoil | Hispanica de Petroleos SA |
| INOC | Iraq National Oil Company |
| Inpex | Indonesia Petroleum Ltd |
| JORC | Jeddah Oil Refinery Company |
| KRPC | Kaduna Refinery & Petrochemical Company |
| KNPC | Kuwait National Petroleum Company KSC |
| KOC | Kuwait Oil Company KSC |
| Lagoven | Lagoven SA |
| Maraven | Maraven SA |
| Marathon | Marathon Petroleum Corp. (MPC) |
| Maxus | Maxus Energy Corporation |
| Mobil | Mobil Oil Corporation |
| NIGC | National Iranian Gas Company |
| NIOC | National Iranian Oil Company |
| NNPC | Nigerian National Petroleum Corporation |
| NOC | National Oil Corporation (Libya) |
| NODCO | National Oil Distribution Company (Qatar) |
| NPHR | New Port Harcourt Refinery |
| Oasis | Oasis Oil Company of the Libya, Inc |
| Occidental | Occidental Petroleum Corporation |
| OMV | OMV Aktiengesellschaft |
| PDVSA | Petroleos de Venezuela SA |
| Perenco | Perenco |
| Pertamina | Perusahaan Pertambangan Minyak Dan Gas Bumi Negara |
| Petrobras | Petrobras |
| PetroChina | PetroChina Co., Ltd |
| Petroecuador | National oil company of Ecuador |
| Petroindustrial | Refinery operations company of Ecuador |
| Petromer Trend | Petromer Trend Corporation |
| Petromin | General Petroleum and Mineral Organization of Saudi Arabia |
| Petronas | Petronas |
| Petroproduccion | Exploration and production oil company of Ecuador |
| Phillips | Phillips Petroleum Company |
| PPMC | Pipeline and Products Marketing Company (Nigeria) |
| QGPC | Qatar General Petroleum Corporation (now Qatar Petroleum) |
| Royal Dutch/Shell | Royal Dutch Petroleum Company, The Netherlands, and Shell Transport and Trading Co, UK |
| Shell Global | Shell Global |
| SINOPEC | China Petroleum & Chemical Corp. (SNP) |
| SNPC | Société Nationale des Pétroles du Congo |
| SOMO Oil | SOMO Oil |
| Sonangol | Sociedade Nacional de CombustÍveis de Angola |
| Sonatrach | Société Nationale de Transport et de Commercialisation des Hydrocarbures |
| Stancal | Standard Oil Company of California |
| Stanvac PT | PT Stanvac Indonesia |
| Tenneco | Tenneco Incorporated |
| Tesoro | Tesoro Indonesia Petroleum Corporation |
| Topco | Texas Overseas Petroleum Company |
| Total | Total Energies SE |
| Union Oil | Union Oil Company of California |
| Valero | Valero Energy Corporation |
| VOO | Veba Oil Operations (Libya) |
| Waha Oil | Waha Oil Company (Libya) |
| Wintershall | Wintershall AG |
| WRPC | Warri Refinery & Petrochemical Company |
| Zadco | Zakum Development Company |
| ZOC | Zueitina Oil Company (Libya) |