| 101 | Medicine Bow Operating Company | Houston, TX 77002 | Oil & Gas Operator | Apr 2014 |
| 102 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | Apr 2026 |
| 103 | Meritage Energy Partners LLC | Denver, CO 80202 | Oil & Gas Operator | Dec 2005 |
| 104 | Merrion Oil & Gas Corp | Farmington, NM 87401 | Oil & Gas Operator | Feb 2026 |
| 105 | Meyer Douglas P | Longmont, CO 80501 | Oil & Gas Operator | Aug 2006 |
| 106 | Mi3 Energy LLC | | Oil & Gas Operator | Feb 2026 |
| 107 | Mid-Con Energy Operating, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Feb 2026 |
| 108 | Midgard Energy Company | The Woodlands, TX 77380 | Oil & Gas Operator | Dec 2014 |
| 109 | Moncrief W A Jr | Fort Worth, TX 76102 | Oil & Gas Operator | Jan 2026 |
| 110 | Montex Drilling Company LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Apr 2026 |
| 111 | MTG Operating Inc | Ridgeland, MS 39158 | Gas Operator | Apr 2011 |
| 112 | Nance Petroleum Corporation | Billings, MT 59103-7168 | Oil & Gas Operator | Nov 2007 |
| 113 | Navigation Powder River LLC | Houston, TX 77024 | Oil & Gas Operator | Feb 2026 |
| 114 | Nielson & Associates, Inc | Cody, WY 82414 | Oil & Gas Operator | Feb 2016 |
| 115 | Noble Energy Inc | Midland, TX 79706 | Oil & Gas Operator | Apr 2026 |
| 116 | Nonsuch Natural Gas Inc | Naples, FL 34108 | Oil & Gas Operator | Feb 2026 |
| 117 | North Finn LLC | Casper, WY 82605 | Oil & Gas Operator | Feb 2026 |
| 118 | Northern Production Co | Gillette, WY 82717 | Oil & Gas Operator | Apr 2013 |
| 119 | Northwest Energy LLC | Buffalo, WY 82834 | Gas Operator | Jan 2010 |
| 120 | Oilfield Salvage & Service Company | Littleton, CO 80120 | Oil & Gas Operator | Jan 2026 |
| 121 | Oryx Energy Company | Dallas, TX 75221 | Oil & Gas Operator | May 2002 |
| 122 | Osborn Heirs Company LTD | San Antonio, TX 78217 | Oil & Gas Operator | Dec 2025 |
| 123 | Oxy USA Inc | Houston, TX 77046 | Oil & Gas Operator | Apr 2026 |
| 124 | P & M Petroleum Management LLC | Denver, CO 80202 | Oil & Gas Operator | Oct 2021 |
| 125 | P.O.&G. Operating, LLC | Houston, TX 77057 | Oil & Gas Operator | Apr 2026 |
| 126 | Pacific Enterprises Oil Co USA | Dallas, TX 75201 | Oil & Gas Operator | Feb 2001 |
| 127 | Peabody Natural Gas LLC | Gillette, WY 82718 | Oil & Gas Operator | Feb 2026 |
| 128 | Peak Powder River Resources LLC | Durango, CO 81301 | Oil & Gas Operator | Feb 2026 |
| 129 | Pearce Oil Company | Manderson, WY 82432 | Oil Operator | Jun 1999 |
| 130 | Pennaco Energy Incorporated | Gillette, WY 82718 | Oil & Gas Operator | Feb 2021 |
| 131 | Petro-Canada Resources (USA) Inc | Denver, CO 80202-472 | Oil & Gas Operator | Feb 2010 |
| 132 | Petro-Lewis Corp. | | Oil & Gas Operator | Feb 1994 |
| 133 | Petrox Resources Inc | Meeker, CO 81641 | Oil & Gas Operator | Feb 2026 |
| 134 | Phillips Petroleum Company | Houston, TX 77251 | Oil & Gas Operator | Mar 2013 |
| 135 | Pioneer Natural Resources USA Inc | Irving, TX 75039 | Oil & Gas Operator | Dec 2025 |
| 136 | Plains Petroleum Operating Co | Denver, CO 80202 | Oil & Gas Operator | Dec 2014 |
| 137 | Prima Exploration, Inc. | Denver, CO 80206 | Oil & Gas Operator | Feb 2026 |
| 138 | Prospective Invest & Trad Co LTD | Tulsa, OK 74170 | Oil & Gas Operator | Aug 2005 |
| 139 | Ranch Oil Company | West Linn, OR 97068 | Oil & Gas Operator | Mar 2026 |
| 140 | RDG Oil & Gas LLC | Post Falls, ID 82854 | Oil & Gas Operator | Mar 2017 |
| 141 | Redstone Gas Partners LLC | Denver, CO 80202 | Gas Operator | Mar 2001 |
| 142 | Redstone Resources Inc | Newcastle, WY 82701 | Gas Operator | Dec 2010 |
| 143 | Richardson Operating Company | Denver, CO 80237 | Oil & Gas Operator | Feb 2026 |
| 144 | Rio Blanco Energy, Inc. | Littleton, CO 80121 | Oil & Gas Operator | Oct 2002 |
| 145 | Sage Butte PRB Operating, LLC | Denver, CO 80202 | Oil & Gas Operator | Feb 2026 |
| 146 | Samson Resources Company LLC | Denver, CO 80202 | Oil & Gas Operator | Feb 2021 |
| 147 | Seven Sisters Oil & Gas LLC | Casper, WY 82602 | Oil & Gas Operator | Jan 2022 |
| 148 | Simon Oil LLC | Kaycee, WY 82639 | Oil Operator | Dec 2025 |
| 149 | Six Bar Oil LLC | Pine Haven, WY 82721 | Oil & Gas Operator | Feb 2026 |
| 150 | SM Energy Company | Midland, TX 79707 | Oil & Gas Operator | Apr 2026 |
| 151 | Sonat Exploration Co. | Houston, TX 77251 | Oil & Gas Operator | Dec 2021 |
| 152 | Southland Royalty Company | Houston, TX 77210 | Oil & Gas Operator | Sep 2011 |
| 153 | Southwestern Production Corporation | Lakewood, CO 80228 | Oil & Gas Operator | Feb 2026 |
| 154 | Storm Cat Energy USA Operating Corp | Denver, CO 80202 | Gas Operator | Jun 2017 |
| 155 | Stripper Oil Company Inc | | Oil Operator | Nov 2025 |
| 156 | Swepi LP | Houston, TX 77079 | Oil & Gas Operator | Jul 2020 |
| 157 | Tbi Exploration Inc | Englewood, CO 801556525 | Oil & Gas Operator | Jun 2011 |
| 158 | Texaco Exploration & Prod | Midland, TX 79702 | Oil & Gas Operator | Aug 2002 |
| 159 | Thomas Operating Company Inc | Greeley, CO 80634 | Oil & Gas Operator | Aug 2008 |
| 160 | Timberline Production Company LLC | Casper, WY 82601 | Oil & Gas Operator | Oct 2020 |
| 161 | Tonka Oil & Gas Production Inc | Buffalo, WY 82834 | Oil & Gas Operator | Sep 1999 |
| 162 | Transhorizon Energy Inc | Cheyenne, WY 82003 | Oil & Gas Operator | Jul 2023 |
| 163 | True Oil LLC | Casper, WY 82602 | Oil & Gas Operator | Feb 2026 |
| 164 | Txo Production Corp. | Ganado, TX 77962 | Oil & Gas Operator | Aug 2022 |
| 165 | Underwood Oil & Gas | Casper, WY 82602 | Oil & Gas Operator | Feb 2026 |
| 166 | Valkyrie Operating LLC | Denver, CO 80202 | Oil & Gas Operator | Feb 2026 |
| 167 | Vector Minerals Corporation | Aurora, CO 80015 | Oil & Gas Operator | Jan 2026 |
| 168 | Warren Enterprises Inc | Gillette, WY 82718 | Oil Operator | Dec 2022 |
| 169 | Webb Resources Inc | | Oil & Gas Operator | Dec 1985 |
| 170 | Wellstar Corporation | Northglenn, CO 80233 | Oil & Gas Operator | Feb 2026 |
| 171 | Westport Oil & Gas Company LP | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2007 |
| 172 | Wexpro Company | Rock Springs, WY 82902-0458 | Oil & Gas Operator | Feb 2026 |
| 173 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Apr 2026 |
| 174 | Wichita River Oil Corporation | Englewood, CO 80111 | Oil & Gas Operator | Apr 2009 |
| 175 | Windsor Energy Group LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Aug 2021 |
| 176 | Wold Energy Partners LLC | Denver, CO 80202 | Oil & Gas Operator | Feb 2022 |
| 177 | Wold Oil Properties Inc | Denver, CO 80203 | Oil & Gas Operator | Feb 2018 |
| 178 | Wolverine Operations LLC | Buffalo, WY 82834 | Gas Operator | Oct 2008 |
| 179 | Woods Petroleum Corporation | Oklahoma City, OK 73112 | Oil & Gas Operator | Mar 2015 |
| 180 | WPX Energy Rocky Mountain LLC | Tulsa, OK 74101 | Oil & Gas Operator | Jan 2026 |
| 181 | WRC Energy LLC | Tulsa, OK 74135 | Oil & Gas Operator | Feb 2026 |
| 182 | Wyoil Corp | Buffalo, WY 82834 | Oil Operator | Aug 2025 |
| 183 | XTO Energy Inc. | Spring, TX 77389 | Oil & Gas Operator | Apr 2026 |
| 184 | Yegen E C | Casper, WY 82604 | Oil & Gas Operator | Mar 2015 |