Basin Electric Cooperative
Billings Generation Inc.
NorthWestern Energy
PPL Montana
Rosebud Energy

Idaho State University
Malmstrom Air Force Base
Montana State University

F.H. Stoltze Land & Lumber
Plum Creek Timber Co.
Roseburg Forest Products Services, Inc.
Stimson Lumber

Ash Grove Cement
Barretts Minerals
Columbia Falls Aluminum
Graymont Western U.S.
Holcim (US) Inc.
Montana Resources
Montana Limestone
Westmoreland Resources

Cargill Environmental Finance
Evergreen Recycling, Inc.
Idahoan Foods
Luzenac America
MT Sulphur & Chemical Co.
FNF Construction
Knife River Construction

Agave Energy Company
Altamont Oil & Gas, Inc.
Anadarko Minerals, Inc.
Armstrong Operating
Ballard Petroleum
Bayswater Exploration & Production
Behm Energy Company
Belle Fourche Pipeline Co.
Burlington Resources, LLC
Calumet Montana Refining
Carrell Oil Company
CHS Inc.
ConocoPhillips Company
Continental Resources, Inc.
Crusader Oil & Gas Company
Denbury Resources
Dakota-3 E&P, LLC
Devon Energy
Eagle Oil & Gas Company
Eighty Eight Oil Co.
Encore Acquisition
Energy Corporation of America
Fidelity Exploration & Production Co.
Halcon Resources Corp.
Havre Pipeline
Hawley and Desimon Oil Company
Hess Corporation
Hiland Partners
Hunt Oil Company
G3 Operating, LLC
Jones Energy LTD
Legacy Reserves Operating
Missouri Basin Well
Missouri River Royalty Corp.
Montalban Oil and Gas Co.
Mountainview Energy
National Oilwell Varco
Nearburg Production Company
Panther Creek Resources
Quicksilver Resources, Inc.
Saga Petroleum
Samson Oil & Gas Limited
Shakespeare Oil and Gas, LLC
Slawson Exploration Company
Summit Gas Gathering
True Oil, LLC
Upton Resources (PennWest)
Western Gas Resources
Whiting Oil and Gas Corporation
Williams Explorations & Productions
WPX Energy, Inc.
XTO Energy Inc.
Zenergy, Inc.
Zenergy Operating Company