| 101 | Western Resources, Inc. | | Oil Operator | Jun 1994 |
| 102 | Westland Oil Development Corp. | Conroe, TX 77305 | Oil & Gas Operator | Mar 2008 |
| 103 | Westport Oil & Gas Company LP | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2007 |
| 104 | Westport Oil And Gas Company Inc | Denver, CO 80202 | Oil & Gas Operator | Feb 2002 |
| 105 | Westport Petroleum Corporation | | Gas Operator | Sep 1985 |
| 106 | Wheeler Oil Company | Sperry, OK 74073-9417 | Oil & Gas Operator | Sep 2025 |
| 107 | Wheless Drilling Company | | Oil & Gas Operator | Dec 1989 |
| 108 | Wheless Drilling Company Et Al | | Oil & Gas Operator | Dec 1989 |
| 109 | Wheless DRLG Co &R.M.Bergstein | | Oil Operator | May 1986 |
| 110 | Wheless Industries, Inc. | Shreveport, LA 71101-5301 | Oil & Gas Operator | Sep 2002 |
| 111 | Wheless Industries-Pelto Oil | | Oil & Gas Operator | Dec 1989 |
| 112 | Whiskey Bay Oil Company | | Oil & Gas Operator | May 1990 |
| 113 | White & Bancroft Et Al | | Oil Operator | Jan 1996 |
| 114 | White & Ellis Drilling, Inc. | Wichita, KS 67206 | Oil & Gas Operator | Sep 2025 |
| 115 | White Contracting Co., Inc. | | Oil Operator | Jan 1991 |
| 116 | White Deer Production Co. Inc. | | Oil Operator | Jan 1999 |
| 117 | White Horse Energy Inc. | | Oil & Gas Operator | Jun 1989 |
| 118 | White Marlin Operating Company, LLC | Houston, TX 77002 | Oil & Gas Operator | Feb 2026 |
| 119 | White Oak Operating Company LLC | Houston, TX 77077 | Oil & Gas Operator | Feb 2026 |
| 120 | White Oil Company | Cement, OK 73017-0515 | Oil Operator | Jun 2002 |
| 121 | White Operating Co., L.L.C. | | Oil & Gas Operator | Oct 2019 |
| 122 | White River Operating LLC | Gilmer, TX 75644 | Oil & Gas Operator | Dec 2025 |
| 123 | White Rock Oil & Gas, LLC | Plano, TX 75024 | Oil & Gas Operator | Feb 2026 |
| 124 | White Sands Energy LLC | | Oil Operator | Jan 2025 |
| 125 | Whitetail Operators LLC | | Oil Operator | Nov 2021 |
| 126 | Whitewing & Whitewing Oil LLC | | Oil & Gas Operator | May 2004 |
| 127 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Feb 2026 |
| 128 | Whiting Petroleum Corporation | Denver, CO 80290 | Oil & Gas Operator | Jan 2025 |
| 129 | Whitney Oil & Gas, LLC | | Oil & Gas Operator | Jan 2025 |
| 130 | Whittier Operating Inc. | Houston, TX 77002 | Oil & Gas Operator | May 2007 |
| 131 | Whittington Operating Company | Houston, TX 77069 | Oil & Gas Operator | Feb 2026 |
| 132 | Whitton Company, Inc. | | Oil & Gas Operator | Jul 2020 |
| 133 | WHK, Inc. | | Oil & Gas Operator | Oct 1993 |
| 134 | Wichita River Oil Corporation | Englewood, CO 80111 | Oil & Gas Operator | Apr 2009 |
| 135 | Wicker Oil Co | | Oil & Gas Operator | Feb 1992 |
| 136 | Wicker, La. Cent. & Clovelly | | Gas Operator | Jul 1983 |
| 137 | Wilco Oil Gas & Expl. Corp. | | Oil & Gas Operator | Mar 1979 |
| 138 | Wilcobill Corporation | | Oil Operator | Dec 1986 |
| 139 | Wilcox Energy Company | | Oil & Gas Operator | Dec 2025 |
| 140 | Wilcox Operating Company | | Oil Operator | Dec 1989 |
| 141 | Wilcox Operating Corporation | Shreveport, LA 71115 | Oil & Gas Operator | Feb 2026 |
| 142 | Wildcat Equipment Co. Inc. | | Oil Operator | Dec 1987 |
| 143 | Wildcat Midstream Caddo LLC | | Oil Operator | May 2017 |
| 144 | Wildcat Well Services, LTD. | | Oil Operator | Oct 1989 |
| 145 | Wildhorse Resources Management Co, LLC | | Oil & Gas Operator | Feb 2018 |
| 146 | Wildhorse Resources, LLC | Houston, TX 77279 | Oil & Gas Operator | Feb 2015 |
| 147 | Wilkerson Oil Company | | Oil Operator | Dec 1991 |
| 148 | Will Energy Corporation | Dallas, TX 75201 | Oil & Gas Operator | Nov 2025 |
| 149 | Will Haristy, Jr. | | Oil & Gas Operator | Nov 2024 |
| 150 | Will-Drill Operating, L.L.C. | Shreveport, LA 71105 | Oil & Gas Operator | Feb 2026 |
| 151 | Will-Drill Production Co., Inc. | Shreveport, LA 71105 | Oil & Gas Operator | Feb 2026 |
| 152 | William D. Pittman | | Oil & Gas Operator | Jun 1991 |
| 153 | William E. Daniels | | Gas Operator | Dec 2013 |
| 154 | William F. Powell | | Oil & Gas Operator | Jun 1979 |
| 155 | William Lagnion | | Oil & Gas Operator | Aug 1998 |
| 156 | William M. Williams | | Oil Operator | May 2018 |
| 157 | William Marvin Hobbs, SR. | | Oil Operator | Aug 2002 |
| 158 | Williams Exploration Company | | Oil & Gas Operator | Dec 1986 |
| 159 | Williams Pressure Service Co. | | Oil Operator | Sep 1985 |
| 160 | Williams-Cody, Inc. | Houston, TX 77060 | Oil & Gas Operator | May 1994 |
| 161 | Williams-Robinson | | Oil Operator | Mar 1988 |
| 162 | Williamson & Smitherman | | Oil & Gas Operator | Dec 2008 |
| 163 | Williamson Oil & Gas, Inc. | Shreveport, LA 71166 | Oil & Gas Operator | Dec 2024 |
| 164 | Williamson Pumping Ser., Inc. | | Oil Operator | Nov 2024 |
| 165 | Willow Springs Production, Inc. | Longview, TX 75606 | Oil & Gas Operator | Sep 1999 |
| 166 | Wilson Production Co Of La,Inc | | Oil & Gas Operator | Apr 1991 |
| 167 | Wilson Well Service | Loco, OK 73442-0114 | Oil & Gas Operator | Mar 2018 |
| 168 | Win Oil Company | Russell, KS 67665 | Oil & Gas Operator | Jul 2021 |
| 169 | Winbeau Oil & Gas Co. | | Oil & Gas Operator | Oct 2013 |
| 170 | Winchester Energy Operating Co. | Austin, TX 78746 | Oil & Gas Operator | Feb 2026 |
| 171 | Winchester Production Company | Shreveport, LA 71129 | Oil & Gas Operator | Nov 2008 |
| 172 | Windfohr Oil Company | | Oil & Gas Operator | May 1980 |
| 173 | Windham Oil Company | | Oil & Gas Operator | Dec 1987 |
| 174 | Windham Oil Corp. | | Oil & Gas Operator | Dec 2024 |
| 175 | Windrush Operating Co., L.L.C. | Longville, LA 70652 | Oil & Gas Operator | Feb 2026 |
| 176 | Windrush Operating Company | | Oil & Gas Operator | Jan 2009 |
| 177 | Windsor Gas Corporation | | Oil & Gas Operator | Aug 1989 |
| 178 | Wintershall Corporation | | Oil & Gas Operator | Oct 1989 |
| 179 | Wintershall Oil & Gas Co | | Oil & Gas Operator | Feb 1980 |
| 180 | Wintershall Oil & Gas Corp | Houston, TX 77027 | Oil & Gas Operator | Jul 1989 |
| 181 | Winwell, L.L.C. | Shreveport, LA 71101 | Oil & Gas Operator | Dec 2007 |
| 182 | Wisenbaker Production Company | Tyler, TX 75702 | Oil & Gas Operator | Oct 2011 |
| 183 | Wiser Oil Co | Denver, CO 80202 | Oil & Gas Operator | Dec 2023 |
| 184 | Witt Oil Production, Inc. | | Oil & Gas Operator | Nov 1984 |
| 185 | Wle, Inc. | | Oil & Gas Operator | Feb 2012 |
| 186 | WLS Corporation | | Oil Operator | Aug 2009 |
| 187 | WM B Hill Production Co | | Oil Operator | Jun 1991 |
| 188 | WM. H. Kenny Consultants, LTD. | | Oil & Gas Operator | Nov 1991 |
| 189 | WM. Herbert Hunt TR.Est. | | Oil & Gas Operator | Oct 1992 |
| 190 | WM. Inabnet | | Gas Operator | Nov 2024 |
| 191 | WM. T. Burton Industries, Inc. | | Oil & Gas Operator | Apr 1988 |
| 192 | WM. Zuhone, Jr. | | Oil & Gas Operator | Aug 1988 |
| 193 | WNR Enterprises', Inc. | | Oil & Gas Operator | Feb 1997 |
| 194 | Woco La, LLC | | Oil Operator | Jan 2025 |
| 195 | Wolf Production, Inc. | Graham, TX 76450 | Oil & Gas Operator | Feb 2026 |
| 196 | Wolfe Oil | Bremen, OH 43107 | Oil Operator | Dec 2024 |
| 197 | Wolverine Exploration Company | Houston, TX 77002 | Oil & Gas Operator | May 2019 |
| 198 | Womack & Nelson | | Gas Operator | Feb 1987 |
| 199 | Womack & Price | | Oil & Gas Operator | Oct 1990 |
| 200 | Womack Prod Co. | | Oil Operator | Feb 1996 |