| 2009 | |
| Aegean Energy, Greece | Oando plc, Nigeria |
| Canamens Energy, UK | Parkmead Group plc, UK |
| Eon - Ruhrgas, UK | Pan Petroleum Ltd |
| Kenda Capital, Netherlands | Severn Energy, UK |
| Meridian Capital, UK | Sasol Petroleum International, UK |
| Greengoldinvest, Brazil | Scottish & Southern Energy plc UK |
| Standard Chartered Bank plc, UK | |
| 2008 | |
| Aegean Energy, Greece | Oando plc, Nigeria |
| Canamens Energy, UK | Parkmead Group plc, UK |
| Eon - Ruhrgas, Germany | Pan Petroleum Ltd |
| Eon - Ruhrgas, UK | Severn Energy, UK |
| Kenda Capital, Netherlands | Sasol Petroleum International, UK |
| Meridian Capital, UK | Scottish & Southern Energy plc, UK |
| Greengoldinvest, Brazil | Standard Chartered Bank plc, UK |
| 2000 to 2007 | |
| Aegean Energy, Greece | Monteco, Brazil |
|
Atlantic Energy, UK |
Oando plc, Nigeria |
|
BHP Billiton, UK |
Parkmead Group plc, UK |
| Buried Hill Energy, UK |
PGS Reservoir, UK |
|
BWP Meruap, Indonesia |
Petrofac Resources International, UK |
| Canamens Energy, UK |
Petrokazakhstan Ltd, UK |
|
Centurion Energy, Canada |
Regal Petroleum Ltd, UK |
| Dhow Services, UK |
RPS, UK |
|
DNO, Norway |
Severn Energy, UK |
|
Eon - Ruhrgas, Germany |
Sasol Petroleum International, UK |
|
Eon - Ruhrgas, Norway |
Shell Technology Ventures, Netherlands |
|
Eon - Ruhrgas, UK |
Standard Bank London, UK |
|
GAB Robins, Australia Pty Ltd |
Standard Chartered Bank plc, UK |
| Gentry Stratic, Canada | Tamoil, Libya |
| Integra Cresswell Ltd, UK |
Trinity Energy Ltd, UK |
|
IPC, Gabon |
UBS, Honk Kong |
|
Kyrgoil, Canada |
UzPEC Ltd, UK |
|
Kenda Capital, Netherlands |
Zhalgyztobemunai, Kazakhstan |
| Meridian Capital, UK | |