| 201 | Hamill Resources, Inc. | Houston, TX 77002 | Oil & Gas Operator | Apr 1999 |
| 202 | Hamill, Claud B. Estate Of | Houston, TX 77002 | Oil & Gas Operator | Nov 1995 |
| 203 | Hamman Oil & Refining Company | Houston, TX 77098 | Oil & Gas Operator | Oct 2025 |
| 204 | Hampton Resources Corporation | Houston, TX 77010 | Oil & Gas Operator | Mar 1996 |
| 205 | Harken Exploration Company | Houston, TX 77079 | Oil & Gas Operator | Mar 2008 |
| 206 | Harman Operating Company, Inc. | Tyler, TX 75702 | Oil & Gas Operator | Dec 2007 |
| 207 | Hawkwood Energy Operating, LLC | Houston, TX 77224 | Oil & Gas Operator | Apr 2022 |
| 208 | Helmerich & Payne, Inc. | Tulsa, OK 74114 | Oil & Gas Operator | Jun 2025 |
| 209 | Hicon Gas Producers, Inc. | New York, NY 10110 | Oil & Gas Operator | Oct 1999 |
| 210 | Hilcorp Energy Company | Houston, TX 77208 | Oil & Gas Operator | Oct 2025 |
| 211 | Hopkins, T. M. Operating Co. | Kilgore, TX 75663 | Oil & Gas Operator | Oct 2025 |
| 212 | Hughey, Gaylord T. SR. Oper. Co. | Tyler, TX 75711 | Oil & Gas Operator | Feb 1998 |
| 213 | Hunt Oil Company | Dallas, TX 75201 | Oil & Gas Operator | Oct 2025 |
| 214 | Hunt Petroleum Corporation | Dallas, TX 75201 | Oil & Gas Operator | Nov 2008 |
| 215 | Huntington Resources Inc | Tulsa, OK 74103 | Oil & Gas Operator | Oct 2006 |
| 216 | Hydrogeo, L.L.C. | Houston, TX 77074 | Oil & Gas Operator | Oct 2025 |
| 217 | Inexco Oil Company | Houston, TX 77210 | Oil & Gas Operator | Mar 2013 |
| 218 | Inland Oil And Gas Company, Inc. | Chireno, TX 75937 | Oil & Gas Operator | Jun 2005 |
| 219 | Ipact | Austin, TX 78734 | Oil & Gas Operator | Oct 2025 |
| 220 | Italian-American Oil Co., Inc. | Tomball, TX 77377 | Oil & Gas Operator | Oct 2025 |
| 221 | J & L Partners | Dallas, TX 75370 | Oil & Gas Operator | Dec 2005 |
| 222 | J-W Operating Company | Christoval, TX 76935 | Oil & Gas Operator | Oct 2025 |
| 223 | J.F.W. Equipment, Inc. | Centerville, TX 75833 | Oil & Gas Operator | Oct 2025 |
| 224 | Jay Management Company LLC | Houston, TX 77057 | Oil & Gas Operator | Oct 2025 |
| 225 | Jetta Operating Company Inc | Fort Worth, TX 76102 | Oil & Gas Operator | Oct 2025 |
| 226 | Jla Resources Company | Austin, TX 78746 | Oil & Gas Operator | Oct 2025 |
| 227 | Josey Oil Company | Houston, TX 77019 | Oil & Gas Operator | Jul 2006 |
| 228 | JTL Operating Co Inc | Katy, TX 77450 | Oil & Gas Operator | Oct 2025 |
| 229 | Kalos Corporation | Tyler, TX 75701 | Oil & Gas Operator | Oct 2025 |
| 230 | Keating Energy, Inc. | Ambler, PA 19002 | Oil & Gas Operator | Oct 2025 |
| 231 | Kennedy & Mitchell, Inc. | Houston, TX 77084 | Oil & Gas Operator | Aug 2013 |
| 232 | Key Production Company, Inc. | Longview, TX 75606 | Oil & Gas Operator | Jun 2025 |
| 233 | Kinlaw Oil Corporation | Dallas, TX 75380 | Oil & Gas Operator | Oct 2025 |
| 234 | Lake Ronel Oil Company | Tyler, TX 75710 | Oil & Gas Operator | Jul 2017 |
| 235 | Largo Oil Company | Longview, TX 75606 | Oil & Gas Operator | Oct 2025 |
| 236 | Layline Energy I LLC | Houston, TX 77024 | Oil & Gas Operator | Dec 2019 |
| 237 | Lazarus Operating, LLC | Kilgore, TX 75663 | Oil Operator | Oct 2025 |
| 238 | Legacy Reserves Operating LP | Denver, CO 80201 | Oil & Gas Operator | Oct 2025 |
| 239 | Lehnertz, G. M. | Tyler, TX 75702 | Oil & Gas Operator | Dec 1998 |
| 240 | Lenert & Pettitt, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Sep 1994 |
| 241 | Linder, John Operating Co., LLC | Gladewater, TX 75647 | Oil & Gas Operator | Oct 2025 |
| 242 | Linop Corporation | Austin, TX 78728 | Oil & Gas Operator | Oct 2025 |
| 243 | Lodi Drilling & Service Co. | Corpus Chrsti, TX 78426 | Oil & Gas Operator | Oct 2025 |
| 244 | Lodi Operating Company LLC | Corpus Chrsti, TX 78426 | Oil & Gas Operator | Oct 2025 |
| 245 | Loin Energy Corporation | La Grange, TX 78945 | Oil & Gas Operator | Oct 2025 |
| 246 | Lone Star Oil & Gas | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 247 | Louisiana Land & Exploration Co. | Houston, TX 77210 | Oil & Gas Operator | Sep 2013 |
| 248 | Lpes, Inc. | Provo, UT 84604 | Oil & Gas Operator | Nov 2018 |
| 249 | Lyon Operating Company Inc.(Iii) | Jacksboro, TX 76458 | Oil & Gas Operator | Oct 2025 |
| 250 | M. Grace, Inc. | Henderson, TX 75653 | Oil & Gas Operator | Oct 2025 |
| 251 | Machin & Associates, Inc. | Longview, TX 75606 | Oil & Gas Operator | Oct 2025 |
| 252 | Main Energy, Inc. | Houston, TX 77079 | Oil & Gas Operator | May 2009 |
| 253 | Majestic Petroleum Corporation | Dallas, TX 75230 | Oil & Gas Operator | Oct 1996 |
| 254 | Manziel Management Corporation | Tyler, TX 75711 | Oil Operator | Feb 2014 |
| 255 | Map Production Co., Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Oct 2025 |
| 256 | Marathon Oil Company | Houston, TX 77252 | Oil & Gas Operator | Aug 2025 |
| 257 | Mariah Energy Corp. | Austin, TX 78716 | Oil & Gas Operator | Apr 1999 |
| 258 | Marino, Charles B. | Tomball, TX 77377 | Oil & Gas Operator | Oct 2025 |
| 259 | Marquee Corporation | Houston, TX 77024 | Oil & Gas Operator | Oct 2025 |
| 260 | Matador Operating Company | Dallas, TX 75240 | Oil & Gas Operator | Jul 2003 |
| 261 | Maximus Operating, LTD. | Kilgore, TX 75663 | Oil & Gas Operator | Oct 2025 |
| 262 | Maynard Oil Co. | Denver, CO 80202 | Oil & Gas Operator | Sep 2004 |
| 263 | McBride, Jerrel L Enterprise Inc | Kilgore, TX 75663 | Oil & Gas Operator | Jun 1999 |
| 264 | McDay Energy Corp. | Dallas, TX 75206 | Oil & Gas Operator | Oct 2025 |
| 265 | McLeod, George L. Inc. | Houston, TX 77079 | Oil & Gas Operator | Sep 2002 |
| 266 | McMoran Oil & Gas LLC | New Orleans, LA 70160 | Oil & Gas Operator | Oct 2021 |
| 267 | McRae & Henry LTD | Golden, CO 80401 | Oil & Gas Operator | May 2022 |
| 268 | McRae Exploration & Prod., Inc. | Houston, TX 77064 | Oil & Gas Operator | Feb 2017 |
| 269 | MD America Energy, LLC | Houston, TX 77224 | Oil & Gas Operator | Apr 2022 |
| 270 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | Oct 2025 |
| 271 | Merritt Operating, Inc. | Mineola, TX 75773 | Oil & Gas Operator | Oct 2025 |
| 272 | Mexco Energy Corporation | Midland, TX 79702 | Oil & Gas Operator | Feb 2020 |
| 273 | Mid-Gulf, Inc. | Brenham, TX 77834 | Oil & Gas Operator | Mar 2008 |
| 274 | Midpar L.P. | Midland, TX 79702 | Oil & Gas Operator | Feb 1995 |
| 275 | Millennium Exploration Co. LLC | San Antonio, TX 78232 | Oil & Gas Operator | Oct 2025 |
| 276 | Miller Energy Inc | Houston, TX 77024 | Oil & Gas Operator | Oct 2016 |
| 277 | Mitchell Energy Company L.P. | Spring, TX 77387 | Oil & Gas Operator | Mar 2008 |
| 278 | Mitchell Energy Corp | Houston, TX 77002 | Oil & Gas Operator | Aug 2013 |
| 279 | Mitsui E&P USA LLC | Houston, TX 77056 | Oil & Gas Operator | Oct 2025 |
| 280 | Mobil Producing TX. & N.M. Inc. | Spring, TX 77389 | Oil & Gas Operator | Oct 2025 |
| 281 | Modern Exploration, Inc. | Sherman, TX 75090 | Oil & Gas Operator | Oct 2025 |
| 282 | Monsanto Company | Indianapolis, IN 46280 | Oil & Gas Operator | Jan 2005 |
| 283 | Moss Petroleum Company | Dallas, TX 75207 | Oil & Gas Operator | Oct 2025 |
| 284 | Musselman, Owen & King Oper.,Inc | Houston, TX 77002 | Oil & Gas Operator | Feb 1998 |
| 285 | Mustang Drilling, Inc. | Henderson, TX 75653 | Oil & Gas Operator | Aug 2024 |
| 286 | Myung And Associates, Inc. | Houston, TX 77056 | Oil & Gas Operator | May 2000 |
| 287 | Nadel And Gussman | Tulsa, OK 74103 | Oil & Gas Operator | May 2007 |
| 288 | Nadel And Gussman, L.L.C. | Tulsa, OK 74119 | Oil & Gas Operator | Oct 2025 |
| 289 | Nance Engineering Inc. | Houston, TX 77058 | Oil & Gas Operator | Mar 2002 |
| 290 | Nasser Oil & Gas, Inc. | The Woodlands, TX 77380 | Oil & Gas Operator | Apr 1998 |
| 291 | NBL Permian LLC | Houston, TX 77070 | Oil & Gas Operator | Aug 2018 |
| 292 | New Gulf Resources, LLC | Tulsa, OK 74133 | Oil & Gas Operator | May 2018 |
| 293 | Newco Oil And Gas, LLC | McKinney, TX 75070 | Oil Operator | Oct 2025 |
| 294 | Newfield Exploration Company | The Woodlands, TX 77380 | Oil & Gas Operator | Jun 2017 |
| 295 | Noble Energy Inc | Midland, TX 79706 | Oil & Gas Operator | Oct 2025 |
| 296 | Nomeco Oil & Gas Co. | Jackson, MI 49204 | Oil & Gas Operator | Dec 1994 |
| 297 | Norcen Explorer, Inc. | Houston, TX 77079 | Oil & Gas Operator | May 1998 |
| 298 | North Central Oil Corp | Houston, TX 77252 | Oil & Gas Operator | Dec 2005 |
| 299 | Oak Energy, LLC | Houston, TX 77027 | Oil & Gas Operator | Oct 2025 |
| 300 | Ocean Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | Aug 2003 |