| AGIP Petroleum |
| Anadarko E&P Company LP |
| ANKOR Energy LLC |
| Antelope Oil Tools |
| Apache Corporation |
| APEX Oil & Gas, Inc |
| Aqueos |
| Arena Offshore, LLC |
| Ashlawn Corporation |
| Bass Enterprises |
| BayCorp Resources |
| Bois D'Arc Offshore Ltd |
| BOPCO, Inc. |
| Breton Energy |
| Browning Oil Company |
| Byron Energy, Inc. |
| Castex Offshore, Inc. |
| CeeKay Gulf Coast, LLC |
| Century Exploration N.O.,LLC |
| Century Exploration |
| CETCO Energy Services |
| Chesapeake Operating, Inc. |
| Chevron North American E&P Co |
| ChevronTexaco |
| Cimarex Energy Co. |
| Clovelly Oil Company, LLC |
| Concho Resouces/COG Operating |
| Conn Energy, LLC |
| ConocoPhillips Company |
| Continental Alloys |
| Continental Resources, Inc. |
| Cox Operating LLC |
| Cronus Offshore, Inc. |
| Denbury Management, Inc. |
| Diamondback Energy, Inc. |
| Dominion Exploration & Production |
| Down Hole Drilling Services |
| Dune Energy |
| EDG, Inc. |
| East Cameron Partners |
| Edison Chouest Offshore |
| Eland Energy, Inc. |
| Eminent Oil Tools |
| Energen |
| Energy XXI Services, LLC |
| Energy Partners, Ltd. |
| ENI US Operating Co. |
| EnVen Energy Ventures, LLC |
| EOG Resources, Inc. |
| ERT GOM INC. |
| Expert Oil & Gas, LLC |
| Express Energy Service |
| ExxonMobil |
| ForceEnergy |
| Forest Oil Corporation |
| Freeport McMoran |
| Furie Operating Alaska, LLC |
| Goldking Energy Corporation |
| Goodrich Petroleum Company, LLC |
| Great Bay Operations, LLC |
| Grosse Tete Well Services |
| Helis Oil & Gas, LLC |
| Helix Energy Solutions, Inc. |
| Houston Energy, LP |
| Hunt Petroleum Corporation |
| Kindee Oil & Gas Louisiana |
| Krewe Energy |
| Legacy Resources Co., LP |
| Legend Natural Gas, LLC |
| Linder Oil Company |
| LLOG Exploration Co. |
| Longview Production Company |
| Louisiana Oilfield Services |
| Magnum Hunter |
| Manti Operating Company |
| Marathon Oil Company |
| Mariner Energy, Inc. |
| Martin-Marks Operating Company |
| Marks Operating Co. |
| Marubeni Oil & Gas |
| McMoran Oil & Gas |
| MC Offshore Petroleum, Inc. |
| Mesa Gulf Coast, LLC |
| Newfield Exploration Company |
| Nexen Petroleum U.S.A. Inc. |
| NEXT Energy Services |
| ORB Exploration, LLC |
| Oxy USA Inc. |
| Palm Energy Offshore, LLC |
| PB Energy Storage Services |
| Performance Drilling |
| Petroci USA, Inc. |
| PetroQuest Energy, LLC. |
| Petsec Energy, Inc. |
| Phoenix Exploration Company |
| Pilot Resources |
| Pioneer Natural Resources, Inc. |
| Pisces Energy, LLC |
| Plains Exploration & Production |
| Prime Natural Resources, Inc. |
| Renaissance Offshore |
| Production Management Corporation |
| Rhino Operating Company, LLC. |
| Ridgelake Energy, Inc. |
| S2 Energy |
| Samedan Oil Company |
| Samson Resources Company |
| Sanchez Oil & Gas Corp. |
| Saratoga Resources, Inc. |
| Silver Hill Energy Partners, LLC |
| Shell Exploration & Production Co |
| Sonoran Energy, Inc. |
| Southwestern Energy Production Co |
| Square Mile Energy, LP |
| Stone Energy Corporation |
| Spartan Offshore Drilling |
| Spinnaker Exploration |
| Survival Systems International |
| Sundown Energy, LP |
| Talos Energy, LLC |
| TANA Exploration Company, LLC |
| Tarpon Operating & Development |
| Tesco Corporation |
| Tetra Applied Technologies, LP |
| Texas Petroleum Investment Co. |
| TDC Energy, LLC |
| Three Rivers Oil & Gas |
| Thyssen Petroleum Company |
| Total E&P USA, Inc. |
| Total Pump & Supply |
| Triangle Oil & Gas, Inc. |
| Upstream Exploration, LLC |
| Venture Oil & Gas |
| Virgin Offshore USA |
| Vitol Resources, Inc. |
| Wapiti Operating, LLC |
| Weatherford International, Ltd. |
| White Knight Resources |
| Wild Well Control, Inc |
| Woodside Energy USA, Inc. |
| W&T Offshore |
| Xpertflo |
| Yuma Companies |