Abraxas Petroleum Corporation
Advantek Waste Management Services
AmeriCo Energy Resources, LLC
Anadarko Petroleum Corporation
Angell Pipeline, LLC
Apache Corporation
Atlas Resource Partners, LP
Atoka
Aurora Resources
Ausbuilt LLC
Azure Midstream Energy, LLC
BHP Billiton
BlueStone Natural Resources II, LLC
Brigham Resources
Bright Automation, Inc.
C&J Equipment Manufacturing
Cabot Oil and Gas
Canyon Petroleum, LLC
Capital Star Oil & Gas Inc.
Carrizo (Eagle Ford), LLC
CDM Resource Management, LLC
Chesapeake Operating, Inc
Chevron Exploration and Production Co.
Cimmarron Gathering, LP
Citation Oil & Gas Corporation
Concho Resources
Conoco Phillips
Control Equipment
Crestwood Midstream Partners LP
Croft Automation
DCP Midstream
Denbury Resources Inc
Devon Energy Corporation
Diamondback Energy
Duncan Lake Pipeline, LLC
EagleRidge Operating, LLC
El Toro Resources LLC
Empire Pipeline Corporation
Encana Oil & Gas (USA), Inc.
Endeavor Energy Resources
Endeavor Natural Gas, LP
Enerflex Energy Systems, Inc.
Energy Transfer (STX)
Energy Transfer Fuel
EnerVest Operating, LLC
Enlink Midstream Partners, LP
EOG Resources
Flamingo Operating LLC
Fluor Enterprises, Inc.
Frio SWD, LLC
GEP Haynesville LLC
Hat Creek Energy LLC
Indigo Haynesville LLC
Kinderhawk Field Service, LLC
Kratech Energy Inc
Laredo Petroleum, Inc.
Layline Energy, LLC
Limestone Exploration II, LLC
Linn Energy
M E Klein & Associates Incorporated
Marathon Oil Company
Matador Resources Company
MECO IV, LLC
Medallion Midstream, LLC
Mid Con Compression LLC
MTN Energy Corp
NGG Gathering Company, LLC
NBL Permian, LLC
Own Resources
Oxy Permian, Ltd.
Paradigm Energy
Parallel Petroleum Corporation
Parsley Energy LLC
Patterson
Petrolog Automation, Inc.
Phoenix SWD, LLC
Pioneer Natural Resources USA, Inc.
Plains All American
Primexx Energy Partners
QEP Energy Company
Questar E & P Company
Red Oak Gas Operating Co LP
Redbud E & P Inc.
Regency Field Services, LLC
Relevant Solutions
Reliance Energy
Resource Production Company
Roil Resources
Rosetta Resources Operating LP
RSP Permian
Sable Permian Resources Land, LLC
Saddle Operating, LLC
Sanchez Oil and Gas Corporation
SandRidge Energy, Inc
Select Energy Services
Sigma Equipment, LLC
SM Energy
SND Operating
South Texas Gas Service
Southcross Energy
Spindletop Oil & Gas Co
Summit Petroleum, LLC
Superior Measurement Solutions
Tabula Rasa Partners, LLC
Tervita LLC
Texas Fabco Solutions, Inc
Texas International Resources
Texas Royalty Corp
Three Rivers Operating Company II
Total – TEP Barnett USA, LLC
Trinity River Energy
Tristate ETX, LLC
Trisun Energy Services
US Energy Development Corp
Vine Oil & Gas LP
WildHorse Resources
XTO Energy