| 201 | Heritage Standard Corporation | Dallas, TX 75206 | Oil & Gas Operator | May 2025 |
| 202 | High Sky Oil & Gas | Midland, TX 79705 | Oil & Gas Operator | Jun 2008 |
| 203 | Highland Production Company | Midland, TX 79701 | Oil & Gas Operator | Mar 1996 |
| 204 | Hillin Prod. Co. | Odessa, TX 79760 | Oil & Gas Operator | Apr 2002 |
| 205 | Hillin, T. A. | Kerrville, TX 78028 | Oil & Gas Operator | Aug 2020 |
| 206 | Home Petroleum Corp | Victoria, TX 77902 | Oil & Gas Operator | May 2025 |
| 207 | Hopper, Harlan | Midland, TX 79702 | Oil & Gas Operator | May 2025 |
| 208 | Hopper, Thornton Co. | Midland, TX 79702 | Oil & Gas Operator | May 2025 |
| 209 | Hunt Oil Company | Dallas, TX 75201 | Oil & Gas Operator | May 2025 |
| 210 | Hunt Petroleum Corporation | Dallas, TX 75201 | Oil & Gas Operator | Nov 2008 |
| 211 | Huntington Energy LLC | Nichols Hill, OK 73116 | Oil & Gas Operator | May 2025 |
| 212 | Ica Energy Operating, L.L.C. | Odessa, TX 79760 | Oil & Gas Operator | May 2025 |
| 213 | Ice Brothers, Inc. | Monahans, TX 79756 | Oil & Gas Operator | Jul 2024 |
| 214 | Impetro Operating LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Nov 2020 |
| 215 | Incline Energy | Midland, TX 79710 | Oil & Gas Operator | May 2025 |
| 216 | Iskandia Energy Operating, Inc. | Houston, TX 77002 | Oil & Gas Operator | May 2025 |
| 217 | Jetta Operating Company Inc | Fort Worth, TX 76102 | Oil & Gas Operator | May 2025 |
| 218 | Johnson And Price | Midland, TX 79702 | Oil & Gas Operator | Dec 1995 |
| 219 | Johnson, Tom E. | Midland, TX 79702 | Oil & Gas Operator | Jun 2008 |
| 220 | Jones, J. Vernon Oil Company | Midland, TX 79708 | Oil & Gas Operator | Mar 2008 |
| 221 | Jones, Skeet Lee | Mentone, TX 79754 | Oil & Gas Operator | May 2025 |
| 222 | JRC Petroleum | Pecos, TX 79772 | Oil & Gas Operator | May 2025 |
| 223 | JRP Resources, L.C. | Midland, TX 79708 | Oil & Gas Operator | May 1995 |
| 224 | JTL Operating Co Inc | Katy, TX 77450 | Oil & Gas Operator | May 2025 |
| 225 | Judah Oil | Artesia, NM 88211 | Oil & Gas Operator | Mar 2010 |
| 226 | K3 Productions LLC | Houston, TX 77269 | Oil & Gas Operator | May 2025 |
| 227 | KCM Management, Inc. | Dallas, TX 75230 | Oil & Gas Operator | Oct 2014 |
| 228 | KCS Medallion Resources, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Nov 2018 |
| 229 | KCS Resources LLC | Houston, TX 77027 | Oil & Gas Operator | Feb 2017 |
| 230 | KCS Resources, Inc. | Houston, TX 77002 | Oil & Gas Operator | Feb 2009 |
| 231 | Keeley Oil, L.L.C. | Dallas, TX 75225 | Oil Operator | May 2025 |
| 232 | Kerr-McGee Corporation | Dallas, TX 75380 | Oil & Gas Operator | Mar 2025 |
| 233 | Kerr-McGee Oil & Gas Onshore LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2017 |
| 234 | Kerr-McGee Oil & Gas Onshore LP | Houston, TX 77046 | Oil & Gas Operator | May 2025 |
| 235 | Kimbell Oil Company Of Texas | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2025 |
| 236 | Kokomo Oil Company | Houston, TX 77227 | Oil & Gas Operator | Apr 1998 |
| 237 | Kuhn Oil Co Inc | Timber Lake, SD 57656 | Oil Operator | Dec 2024 |
| 238 | Laguna Petroleum Corporation | Houston, TX 77046 | Oil & Gas Operator | May 2025 |
| 239 | Lario Oil & Gas Company | Odessa, TX 79762 | Oil & Gas Operator | May 2025 |
| 240 | Last Mile Production, LLC | Austin, TX 78746 | Oil & Gas Operator | May 2025 |
| 241 | Latex Petroleum Corp. | Houston, TX 77090 | Oil & Gas Operator | Aug 2012 |
| 242 | Legacy Reserves Operating LP | Denver, CO 80201 | Oil & Gas Operator | May 2025 |
| 243 | Limark Corporation | Midland, TX 79702 | Oil & Gas Operator | Dec 2003 |
| 244 | Lincoln Rock Corporation | Northfield, IL 60093 | Oil & Gas Operator | Jul 2003 |
| 245 | Lomak Production Company | Fort Worth, TX 76102 | Oil & Gas Operator | Aug 1998 |
| 246 | Lone Star Oil & Gas | Midland, TX 79702 | Oil & Gas Operator | May 2025 |
| 247 | LRR Pecos Valley, LLC | Houston, TX 77002 | Oil & Gas Operator | May 2025 |
| 248 | M & J Energy, Inc. | Breckenridge, CO 80424 | Oil & Gas Operator | May 2025 |
| 249 | M-T Petroleum, Inc. | Andrews, TX 79714 | Oil & Gas Operator | Mar 2008 |
| 250 | M2 Squared Operating, LLC | Rockwall, TX 75032 | Oil Operator | May 2025 |
| 251 | Madison And Wright LLC | The Colony, TX 75056 | Oil & Gas Operator | May 2025 |
| 252 | Manhattan Petroleum, Inc. | Midland, TX 79702 | Oil & Gas Operator | May 2025 |
| 253 | Manzano LLC | Roswell, NM 88202 | Oil & Gas Operator | May 2025 |
| 254 | Manzano Oil Corporation | Roswell, NM 88202 | Oil & Gas Operator | Feb 2005 |
| 255 | Maralo, Inc. | Midland, TX 79702 | Oil & Gas Operator | Dec 1998 |
| 256 | Maralo, LLC | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 257 | Marathon Oil Company | Houston, TX 77252 | Oil & Gas Operator | Mar 2025 |
| 258 | Mariah Energy Corp. | Austin, TX 78716 | Oil & Gas Operator | Apr 1999 |
| 259 | Marshall & Winston, Inc. | Midland, TX 79710 | Oil & Gas Operator | May 2025 |
| 260 | Matador Production Company | Dallas, TX 75240 | Oil & Gas Operator | May 2025 |
| 261 | McCabe Energy, Inc. | Midland, TX 79702 | Oil & Gas Operator | Aug 2009 |
| 262 | McClure Oil Company, Inc. | Midland, TX 79701 | Oil & Gas Operator | May 2025 |
| 263 | McKinney, M. H. | Midland, TX 79701 | Oil & Gas Operator | Apr 1995 |
| 264 | Memorial Production Operating LLC | Houston, TX 77002 | Oil & Gas Operator | May 2025 |
| 265 | Meridian Oil Inc. | Houston, TX 77210 | Oil & Gas Operator | Aug 1996 |
| 266 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | May 2025 |
| 267 | Mesquite SWD Inc | Carlsbad, NM 88221 | Oil & Gas Operator | May 2025 |
| 268 | Mewbourne Oil Company | Tyler, TX 75711 | Oil & Gas Operator | May 2025 |
| 269 | Mexco Energy Corporation | Midland, TX 79702 | Oil & Gas Operator | Feb 2020 |
| 270 | MGF Oil Corporation | Tulsa, OK 74121 | Oil & Gas Operator | Jun 1998 |
| 271 | Michaelson Producing Company | MC Camey, TX 79752 | Oil & Gas Operator | May 2025 |
| 272 | Miltex Oil Company | Boerne, TX 78006 | Oil & Gas Operator | May 2025 |
| 273 | Miocene Oil & Gas, Inc. | Englewood, CO 80155 | Oil & Gas Operator | Jul 1998 |
| 274 | Miocene Oil & Gas, LTD. | Englewood, CO 80110 | Oil & Gas Operator | May 2025 |
| 275 | Mna Enterprises LTD. Co. | Hobbs, NM 88242 | Oil & Gas Operator | May 2025 |
| 276 | Mobil Producing TX. & N.M. Inc. | Spring, TX 77389 | Oil & Gas Operator | May 2025 |
| 277 | Montgomery Petroleum, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Aug 2007 |
| 278 | Mueller Engineering Corp. | Corpus Chrsti, TX 78476 | Oil & Gas Operator | Feb 2002 |
| 279 | MW Petroleum Corporation | Houston, TX 77056 | Oil & Gas Operator | Mar 2015 |
| 280 | Naco Production | Midland, TX 79708 | Oil & Gas Operator | Aug 2003 |
| 281 | Nadel And Gussman Permian,L.L.C. | Tulsa, OK 74103 | Oil & Gas Operator | May 2025 |
| 282 | Narbo Farms, LTD. | Midland, TX 79702 | Oil & Gas Operator | May 2025 |
| 283 | NBL Permian LLC | Houston, TX 77070 | Oil & Gas Operator | Aug 2018 |
| 284 | Neostar Energy Co. | Crossville, TN 38572 | Oil & Gas Operator | Feb 2019 |
| 285 | New Horizon Exploration, Inc. | Richardson, TX 75081 | Oil & Gas Operator | Jun 2006 |
| 286 | Newton Corp.,The | Dallas, TX 75251 | Oil & Gas Operator | May 2025 |
| 287 | Noble Energy Inc | Midland, TX 79706 | Oil & Gas Operator | May 2025 |
| 288 | O'Brien, George H. Jr. | Midland, TX 79701 | Oil & Gas Operator | Jun 1994 |
| 289 | O'Neill Properties, LTD. | Midland, TX 79702 | Oil & Gas Operator | May 2025 |
| 290 | O. H. B. Inc. | San Angelo, TX 76902 | Oil & Gas Operator | Sep 2019 |
| 291 | Oasis Petroleum Permian LLC | Houston, TX 77002 | Oil & Gas Operator | May 2025 |
| 292 | Occidental Energy Marketing, Inc. | Houston, TX 77227 | Gas Operator | Sep 2015 |
| 293 | Occidental Permian LTD. | Houston, TX 77046 | Oil & Gas Operator | May 2025 |
| 294 | Odessa Exploration, Inc. | Midland, TX 79702 | Oil & Gas Operator | May 2025 |
| 295 | Ogx Operating, LLC | Midland, TX 79702 | Oil & Gas Operator | May 2025 |
| 296 | Ogx Resources LLC | Midland, TX 79702 | Oil & Gas Operator | Oct 2011 |
| 297 | Oliver Oil & Gas | Midland, TX 79702 | Oil & Gas Operator | May 2025 |
| 298 | Omni Petroleum Corporation | Austin, TX 78738 | Oil & Gas Operator | May 2025 |
| 299 | Opal Resources Operating Co.,LLC | Cypress, TX 77429 | Oil & Gas Operator | Jan 2019 |
| 300 | Oryx Energy Company | Dallas, TX 75221 | Oil & Gas Operator | May 2002 |