Abraxas Petroleum Corporation
American Oil & Gas
Axiom Energy
Basin Electric
Basin Hills Operating Company
Berenergy Corporation
Bighorn Gas Gathering, LLC.
Black Diamond Energy, Inc.
Blue Creek Energy
BP America Production Co.
Brown, Drew & Massey, LLP
Carpenter & Sons, Inc.
Citation Oil and Gas Corporation
Continental Industries
Devon Energy Corporation
Diamond Oil
Energy Equity
Exxon Mobil Production Company
Farleigh Oil Properties
Finley Energy Resources
Iron Creek Energy, LLC.
J.M. Huber Corporation
Kennedy Oil
Lonabaugh & Riggs
Marathon
Mid-Con Energy Corp.
North Finn, LLC
Peabody Energy Corp.
PEDCo
Pinnacle Gas Resources, Inc.
Shell Exploration and Production
St. Mary Land & Exploration Company
Sundance Energy
The Termo Company
Thomas Operating Co.
Toungue River Resources
Trend Exploration Company
W. A. Moncrief, Jr.
Western Interior Resources
Wildhorse Exploration
Windsor Energy Group
Wold Oil Properties
Wyoming Oil and Gas Conservation Commission
Wyoming State Geological Survey
Yates Petroleum Corporation