Murphy Oil Corporation

Mosaic Oil

Marathon Oil Corporation

MMS Petroleum Services Limited

A.P. Moller - Maersk

Lundin Petroleum AB

Lukoil Oil Company

Kuwait National Petroleum Company (KNPC)

PGNiG

Korea National Oil Corporation (KNOC)

IFP-Lyon

Husky Energy Inc.

PetroKazakhstan Inc

Hindustan Petroleum Corporation Limited

Halliburton

Givot Olam Oil Ltd.

Gasum

Gaz de France

GeoScience Limited

Galp Energia

Exxon Mobil

Tullow Oil plc

Eni

Esso

Ecopetrol S.A.

TOTAL

Dana Petroleum plc

CSIRO Exploration and Mining

ConocoPhillips

CGGVeritas

Chinese Petroleum Corporation (CPC)

Hunt Oil Company

Chevron

CanArgo Energy Corporation

CALTEX

Cairn Energy PLC

Cabot Oil & Gas Corporation

Bay State Gas Company

Australian Worldwide Exploration Limited (AWE)

Aruba Petroleum, Inc.

BP

Anonima Petroli Italiana SpA

Anadarko Petroleum Corporation

Hess Corporation

Statoil (U.K.) Limited

Abu Dhabi National Oil Company (ADNOC)