| 101 | Mapco Oil Company | | Oil & Gas Operator | Jan 1985 |
| 102 | Mar/Reg Investments | Irving, TX 75016 | Oil & Gas Operator | Jul 1999 |
| 103 | Marathon Oil Company | Houston, TX 77252 | Oil & Gas Operator | Apr 2026 |
| 104 | Martens & Peck Production Co | Denver, CO 80222 | Oil & Gas Operator | Feb 1997 |
| 105 | Martin Exploration | Westminster, CO 80030 | Oil & Gas Operator | Dec 1993 |
| 106 | Matrix Production Company | Sugar Land, TX 77478 | Oil & Gas Operator | Apr 2026 |
| 107 | McCartney Engineering LLC | Wheat Ridge, CO 80033 | Oil & Gas Operator | Apr 2026 |
| 108 | Meerkat Logistics And Operations LLC | Tuscaloosa, AL 35401 | Oil Operator | Apr 2026 |
| 109 | Mels Water Service Inc | Lysite, WY 82642 | Oil Operator | Mar 2013 |
| 110 | Memorial Exploration Company | Saint Louis, MO 63105 | Oil & Gas Operator | Aug 1996 |
| 111 | Memorial Production Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Jun 2026 |
| 112 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | Jun 2026 |
| 113 | Meritage Energy Partners LLC | Denver, CO 80202 | Oil & Gas Operator | Dec 2005 |
| 114 | Merrion Oil & Gas Corp | Farmington, NM 87401 | Oil & Gas Operator | Apr 2026 |
| 115 | Michigan-Wisconsin Pipe Line Co | | Oil & Gas Operator | Dec 1983 |
| 116 | Mobil Expl & Producing North America Inc | | Oil & Gas Operator | Nov 1986 |
| 117 | Moncrief W A Jr | Fort Worth, TX 76102 | Oil & Gas Operator | Apr 2026 |
| 118 | Monsanto Company | Indianapolis, IN 46280 | Oil & Gas Operator | Jan 2005 |
| 119 | Montex Drilling Company LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Jun 2026 |
| 120 | Monument Global Resources Inc | Dallas, TX 75243 | Oil & Gas Operator | Jan 2025 |
| 121 | Morsey Oil & Gas Corporation | Corpus Christ, TX 78401 | Oil & Gas Operator | Jun 2026 |
| 122 | Mosbacher Production Co. | Houston, TX 77001 | Oil & Gas Operator | Aug 1984 |
| 123 | Mountain Petroleum Corp | Denver, CO 80202 | Oil & Gas Operator | Apr 2013 |
| 124 | MRD Operating LLC (Delaware) | Houston, TX 77010 | Oil & Gas Operator | Jul 2015 |
| 125 | Nance Petroleum Corporation | Billings, MT 59103-7168 | Oil & Gas Operator | Nov 2007 |
| 126 | Natural Gas Processing Company | Worland, WY 82401 | Oil & Gas Operator | Mar 2026 |
| 127 | Newfield Production Company | The Woodlands, TX 77380-2764 | Oil & Gas Operator | Jul 2022 |
| 128 | Noble Energy Inc | Midland, TX 79706 | Oil & Gas Operator | Jun 2026 |
| 129 | Nortex Gas & Oil Co | Tulsa, OK 74135 | Oil & Gas Operator | Sep 1993 |
| 130 | Northstar Operating Company | Midland, TX 79702 | Oil & Gas Operator | Jun 2024 |
| 131 | Northwest Exploration | | Oil & Gas Operator | Dec 1984 |
| 132 | Nova Energy Inc | Casper, WY 82601 | Oil & Gas Operator | Oct 2020 |
| 133 | Nova Petroleum Cororation | | Oil & Gas Operator | Mar 1987 |
| 134 | Oilfield Consultants | | Oil & Gas Operator | Dec 1987 |
| 135 | Omimex Petroleum Inc (Co) | Newcastle, WY 82701 | Oil & Gas Operator | May 2001 |
| 136 | Omni Operating Company | Osage, WY 82723 | Oil & Gas Operator | Sep 2001 |
| 137 | Oneida Energy Corporation | Tulsa, OK 74137 | Oil & Gas Operator | Jul 2003 |
| 138 | Oryx Energy Company | Dallas, TX 75221 | Oil & Gas Operator | May 2002 |
| 139 | Ovintiv USA Inc. | Denver, CO 80202 | Oil & Gas Operator | Jun 2026 |
| 140 | P & M Petroleum Management LLC | Denver, CO 80202 | Oil & Gas Operator | Oct 2021 |
| 141 | Pacific Enterprises Oil Co USA | Dallas, TX 75201 | Oil & Gas Operator | Feb 2001 |
| 142 | PDS Resources LLC | | Oil & Gas Operator | Mar 2026 |
| 143 | Pendragon Energy Partners Inc | Midland, TX 79701 | Oil & Gas Operator | Nov 2009 |
| 144 | Petro-Lewis Corp. | | Oil & Gas Operator | Feb 1994 |
| 145 | Petroleum Resource Management Corp | Denver, CO 80203 | Oil & Gas Operator | Apr 2026 |
| 146 | Phillips Petroleum Company | Houston, TX 77251 | Oil & Gas Operator | Mar 2013 |
| 147 | Phoenix Production Company | Cody, WY 82414-3607 | Oil & Gas Operator | Oct 2023 |
| 148 | Pioneer Oil & Gas | South Jordan, UT 84095 | Oil & Gas Operator | Jan 2014 |
| 149 | Plains Petroleum Operating Co | Denver, CO 80202 | Oil & Gas Operator | Dec 2014 |
| 150 | Prenalta Corporation | Terrytown, NY 10591 | Oil & Gas Operator | Jan 1997 |
| 151 | Prime Operating Company | Midland, TX 79705 | Oil & Gas Operator | Jun 2026 |
| 152 | Purewest Resources Inc | Pinedale, WY 82941 | Oil & Gas Operator | Mar 2026 |
| 153 | Qep Energy Company | Midland, TX 79701 | Oil & Gas Operator | Mar 2026 |
| 154 | Quicksilver Resources Inc | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2018 |
| 155 | Quinoco Petroleum Inc | | Oil & Gas Operator | Dec 1990 |
| 156 | Rathpro Inc | Douglas, WY 82633 | Oil & Gas Operator | Feb 1994 |
| 157 | Richardson Operating Company | Denver, CO 80237 | Oil & Gas Operator | Mar 2026 |
| 158 | Saba Energy Of Texas Inc | Houston, TX 77042 | Oil & Gas Operator | Jul 2007 |
| 159 | Saga Petroleum LLC Of Colorado | Norman, OK 73072 | Oil & Gas Operator | Jun 2026 |
| 160 | Salt Creek Operating LLC | FT Morgan, CO 80701 | Oil & Gas Operator | Mar 2020 |
| 161 | Samedan Oil Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2019 |
| 162 | Samson Resources Company LLC | Denver, CO 80202 | Oil & Gas Operator | Feb 2021 |
| 163 | Sauer Bill Oil & Gas Company LLC | Casper, WY 82604 | Oil & Gas Operator | Jun 1999 |
| 164 | Sayers Operating Company | Midland, TX 79705 | Oil & Gas Operator | Feb 2005 |
| 165 | Slaughter J M Oil Company | Fort Worth, TX 76116 | Oil & Gas Operator | Jan 2001 |
| 166 | SM Energy Company | Midland, TX 79707 | Oil & Gas Operator | Jun 2026 |
| 167 | Snyder Oil Corporation | Houston, TX 77024 | Oil & Gas Operator | Mar 2008 |
| 168 | South Pass Petroleum Inc | Casper, WY 82601 | Oil & Gas Operator | Apr 2026 |
| 169 | Southern Mineral Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2001 |
| 170 | Southland Royalty Company LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Jul 2021 |
| 171 | St Oil Company | Denver, CO 80264-2101 | Oil & Gas Operator | Dec 2010 |
| 172 | Stone Energy Corporation | Denver, CO 80202-2828 | Oil & Gas Operator | Oct 2014 |
| 173 | Swepi LP | Houston, TX 77079 | Oil & Gas Operator | Jul 2020 |
| 174 | Swift Energy Company | Houston, TX 77060 | Oil & Gas Operator | Mar 2021 |
| 175 | Taylor Oil #13 LLC | Lander, WY 82520 | Oil Operator | Jan 2026 |
| 176 | Tbi Exploration Inc | Englewood, CO 801556525 | Oil & Gas Operator | Jun 2011 |
| 177 | TCF Inc | | Gas Operator | Dec 1993 |
| 178 | Tenneco Oil Company | Oklahoma City, OK 73125 | Oil & Gas Operator | Dec 2025 |
| 179 | Terry Production Co | Stroud, OK 74079-0475 | Oil & Gas Operator | Aug 2008 |
| 180 | Texaco Exploration & Prod | Midland, TX 79702 | Oil & Gas Operator | Aug 2002 |
| 181 | The Brinkerhoff Company | Denver, CO 80202 | Oil & Gas Operator | Dec 2017 |
| 182 | Tidemark Exploration | Tulsa, OK 74170 | Oil & Gas Operator | May 2005 |
| 183 | Timberline Energy Inc | Franklin, PA 16323-0269 | Oil & Gas Operator | Dec 2025 |
| 184 | Timberline Production Company LLC | Casper, WY 82601 | Oil & Gas Operator | Oct 2020 |
| 185 | Toc-Rocky Mountain Inc | | Oil & Gas Operator | Oct 2013 |
| 186 | Transhorizon Energy Inc | Cheyenne, WY 82003 | Oil & Gas Operator | Jul 2023 |
| 187 | Tressler John R & IVa M | | Oil Operator | Apr 1989 |
| 188 | Trigg Drilling Company Inc | Oklahoma City, OK 73105 | Oil & Gas Operator | Jan 2013 |
| 189 | Trinity Resources, Inc. | Houston, TX 77277 | Oil & Gas Operator | May 2020 |
| 190 | Trout Kye Jr | | Oil & Gas Operator | Dec 2010 |
| 191 | True Oil LLC | Casper, WY 82602 | Oil & Gas Operator | Apr 2026 |
| 192 | Turner Smith & Associates | Englewood, CO 80111 | Oil & Gas Operator | May 1994 |
| 193 | Tyrex Oil Company | Casper, WY 82602 | Oil & Gas Operator | May 1997 |
| 194 | Union Oil Co Of California | Midland, TX 79706 | Oil & Gas Operator | Jan 2022 |
| 195 | United Natural Gas LLC | Denver, CO 80202 | Oil & Gas Operator | Feb 2020 |
| 196 | United Natural Resources Corp | | Oil Operator | Jan 1986 |
| 197 | Us Ore Corporation | Pacific Beach, CA 92109 | Oil Operator | Feb 2014 |
| 198 | Valkyrie Operating LLC | Denver, CO 80202 | Oil & Gas Operator | Apr 2026 |
| 199 | Wagner & Brown Limited Partnership | Midland, TX 79701 | Oil & Gas Operator | Feb 2013 |
| 200 | Warrego Oil & Gas LLC | Lander, WY 82520 | Oil Operator | May 2018 |