| 201 | Kaiser-Francis Oil Company | Tulsa, OK 74121 | Oil & Gas Operator | Dec 2025 |
| 202 | KCS Resources, Inc. | Houston, TX 77002 | Oil & Gas Operator | Feb 2009 |
| 203 | Kebo Oil & Gas, Inc. | Portland, TX 78374 | Oil & Gas Operator | Dec 2025 |
| 204 | Keith F Walker Oil & Gas Company LLC | Oklahoma City, OK 73114 | Oil & Gas Operator | Sep 2025 |
| 205 | Kendrick, Barbara S. | Baytown, TX 77521 | Oil Operator | Dec 2025 |
| 206 | Kendrick, Paul W. | Baytown, TX 77520 | Oil & Gas Operator | Sep 2005 |
| 207 | Kerr-McGee Corporation | Dallas, TX 75380 | Oil & Gas Operator | Aug 2025 |
| 208 | Kerr-McGee Oil & Gas Onshore LP | Houston, TX 77046 | Oil & Gas Operator | Dec 2025 |
| 209 | Key Energy Of Colorado, Inc. | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2016 |
| 210 | Killam Oil Co., LTD. | Laredo, TX 78042 | Oil & Gas Operator | Dec 2025 |
| 211 | Killam Oil Company | Laredo, TX 78042 | Oil & Gas Operator | Mar 1994 |
| 212 | Kinder Morgan Tejas Pipeline LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2025 |
| 213 | Kovar Operating, LLC | Victoria, TX 77901 | Oil & Gas Operator | Sep 2021 |
| 214 | L & R Energy Corporation | Spearman, TX 79081 | Oil & Gas Operator | Nov 2014 |
| 215 | L.O.G. Energy Exploration, LTD. | Laredo, TX 78041 | Oil & Gas Operator | Dec 2025 |
| 216 | Lakeshore Operating, LLC | Wichita, KS 67203 | Oil & Gas Operator | Dec 2025 |
| 217 | Laredo Energy | Houston, TX 77002 | Oil & Gas Operator | Jun 2016 |
| 218 | Laredo Energy Operating, LLC | Houston, TX 77024 | Oil & Gas Operator | Nov 2022 |
| 219 | Laredo Energy, LP | Houston, TX 77040 | Oil & Gas Operator | Oct 2003 |
| 220 | Left Behind Recovery, LLC | Luling, TX 78648 | Oil & Gas Operator | Dec 2025 |
| 221 | Legend Natural Gas II, LP | Houston, TX 77094 | Oil & Gas Operator | Feb 2015 |
| 222 | Legend Natural Gas, LP | Houston, TX 77084 | Oil & Gas Operator | Aug 2004 |
| 223 | Linn Operating, Inc. | Houston, TX 77002 | Oil & Gas Operator | May 2017 |
| 224 | Linn Operating, LLC | Houston, TX 77002 | Oil & Gas Operator | Jan 2019 |
| 225 | Lobo Energy, Inc. | Laredo, TX 78044 | Oil & Gas Operator | Nov 1996 |
| 226 | Lobo Operating, Inc. | Houston, TX 77077 | Oil & Gas Operator | Dec 2024 |
| 227 | Lobo Resources, LTD. | Houston, TX 77077 | Oil & Gas Operator | Apr 1994 |
| 228 | Low-End Oil LLC | Austin, TX 78748 | Oil Operator | Dec 2025 |
| 229 | Maggert Energy Corp. | Spring, TX 77387 | Gas Operator | Jun 1998 |
| 230 | Magna Operating, LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2025 |
| 231 | Magnum Producing & Operating Co. | Corpus Chrsti, TX 78471 | Oil & Gas Operator | Jan 2004 |
| 232 | Magnum Producing, LP | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Dec 2025 |
| 233 | Marathon Oil Company | Houston, TX 77252 | Oil & Gas Operator | Oct 2025 |
| 234 | Marmaton Oil Company | Houston, TX 77002 | Oil & Gas Operator | Jul 1998 |
| 235 | Marquee Corporation | Houston, TX 77024 | Oil & Gas Operator | Dec 2025 |
| 236 | Marwell Petroleum LTD Partnrship | Houston, TX 77027 | Oil & Gas Operator | Dec 2025 |
| 237 | Marwell Petroleum, Inc. | Houston, TX 77057 | Oil & Gas Operator | Apr 2006 |
| 238 | McRae, Nathan Rathburn | Hebbronville, TX 78361 | Oil & Gas Operator | Apr 1994 |
| 239 | Medallion Oil Company | Houston, TX 77251 | Oil & Gas Operator | Jan 2012 |
| 240 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | Dec 2025 |
| 241 | Metano Energy, LP | San Antonio, TX 78216 | Oil & Gas Operator | Aug 2008 |
| 242 | Michael Petroleum Corporation | Houston, TX 77040 | Oil & Gas Operator | Dec 2001 |
| 243 | Midpar L.P. | Midland, TX 79702 | Oil & Gas Operator | Feb 1995 |
| 244 | Milagro Exploration, LLC | Houston, TX 77010 | Oil & Gas Operator | Aug 2018 |
| 245 | Millennium Exploration Co. LLC | San Antonio, TX 78232 | Oil & Gas Operator | Dec 2025 |
| 246 | Mission Resources Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2008 |
| 247 | Mobil Oil Corporation | Houston, TX 77210 | Oil & Gas Operator | Dec 2007 |
| 248 | Mobil Producing TX. & N.M. Inc. | Spring, TX 77389 | Oil & Gas Operator | Dec 2025 |
| 249 | Mohican Operating, L.L.C. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Apr 2021 |
| 250 | Mortimer Production Company | San Antonio, TX 78209 | Oil & Gas Operator | Dec 2025 |
| 251 | Mote Resources, Inc. | Dallas, TX 75225 | Oil & Gas Operator | Dec 2004 |
| 252 | Mueller Engineering Corp. | Corpus Chrsti, TX 78476 | Oil & Gas Operator | Feb 2002 |
| 253 | Mueller Exploration, Inc. | Portland, TX 78374 | Oil & Gas Operator | Dec 2025 |
| 254 | Mustang Oil & Gas Corporation | Wichita Falls, TX 76308 | Oil & Gas Operator | Jul 2021 |
| 255 | Natural Gas Pipeline Co Of Amer. | Houston, TX 77002 | Gas Operator | Jul 2008 |
| 256 | Natural Reserves Group, Inc. | Houston, TX 77057 | Oil & Gas Operator | Jun 1993 |
| 257 | Newfield Exploration Company | The Woodlands, TX 77380 | Oil & Gas Operator | Jun 2017 |
| 258 | Newgulf Petroleum, LLC | San Antonio, TX 78209 | Oil & Gas Operator | Sep 2017 |
| 259 | Newman Operating Company | Freer, TX 78357 | Oil & Gas Operator | Jun 2021 |
| 260 | Noble Energy Inc | Midland, TX 79706 | Oil & Gas Operator | Dec 2025 |
| 261 | Nordstrand Engineering Inc | Houston, TX 77019 | Oil & Gas Operator | Dec 2025 |
| 262 | Norgas Energy | Lakehills, TX 78063 | Oil & Gas Operator | Dec 2025 |
| 263 | North Central Oil Corp | Houston, TX 77252 | Oil & Gas Operator | Dec 2005 |
| 264 | Oak Valley Operating, LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Jun 2015 |
| 265 | Ocean Energy Inc | Houston, TX 77002 | Oil & Gas Operator | Aug 2003 |
| 266 | Okie Operating Company, LTD. | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2025 |
| 267 | Omega Energy Corp. | Graham, TX 76450 | Oil & Gas Operator | Dec 2025 |
| 268 | Outline Oil Company LLC | Beeville, TX 78104 | Oil Operator | Dec 2025 |
| 269 | Oxy USA Inc | Houston, TX 77046 | Oil & Gas Operator | Dec 2025 |
| 270 | Paladar Investments I, L.L.C. | Houston, TX 77090 | Oil & Gas Operator | Feb 2013 |
| 271 | Paleo Oil Company LLC | Corpus Chrsti, TX 78411 | Oil & Gas Operator | Dec 2025 |
| 272 | Paloma Operating, LLC | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Dec 2025 |
| 273 | Paloma Resources, LLC | Houston, TX 77002 | Oil & Gas Operator | Jun 2018 |
| 274 | Panther Creek Resources, LLC | Denver, CO 80202 | Oil & Gas Operator | May 2012 |
| 275 | Parker & Parsley Development L.P | Midland, TX 79702 | Oil & Gas Operator | Oct 2007 |
| 276 | Parker & Parsley Producing LP | Midland, TX 79702 | Oil & Gas Operator | Oct 1997 |
| 277 | Pennzenergy Exp. & Prod., L.L.C. | Houston, TX 77210 | Oil & Gas Operator | Mar 2000 |
| 278 | Pennzoil Exploration & Production Co. | Carthage, TX 75633 | Oil & Gas Operator | Mar 2008 |
| 279 | Peoples Energy Prod.-TX, L.P. | Houston, TX 77002 | Oil & Gas Operator | Sep 2007 |
| 280 | Petra Oleum Corp. | Midland, TX 79702 | Oil & Gas Operator | Dec 2025 |
| 281 | Petro-Hunt, L.L.C. | Dallas, TX 75201 | Oil & Gas Operator | Dec 2025 |
| 282 | Petropoint Energy Operating, LLC | Houston, TX 77098 | Oil & Gas Operator | Dec 2025 |
| 283 | Petroquest Exploration, Inc. | Dallas, TX 75251 | Oil & Gas Operator | Mar 2008 |
| 284 | Pheffer Oil, L.L.C. | Laredo, TX 78041 | Oil Operator | Jul 2021 |
| 285 | Phillips Petroleum Company | Houston, TX 77251 | Oil & Gas Operator | Mar 2013 |
| 286 | Pierco Energy Corp. | Dallas, TX 75231 | Oil & Gas Operator | Dec 2025 |
| 287 | Pintail Production Co., Inc. | Fort Worth, TX 76132 | Oil & Gas Operator | Dec 2025 |
| 288 | Pioneer Natural Res. USA, Inc. | Spring, TX 77389 | Oil & Gas Operator | Dec 2025 |
| 289 | Pioneer Resources Producing, L.P | Irving, TX 75039 | Oil & Gas Operator | Feb 2001 |
| 290 | Placid Oil Company | Houston, TX 77227 | Oil & Gas Operator | Mar 2008 |
| 291 | Plains Exploration & Prod. Co. | Houston, TX 77002 | Oil & Gas Operator | Jul 2013 |
| 292 | Pogo Producing Company | Houston, TX 77002 | Oil & Gas Operator | Jan 2008 |
| 293 | Pogo Producing Company LLC | Houston, TX 77002 | Oil & Gas Operator | Sep 2025 |
| 294 | Pressly Oil Interest, Inc. | San Antonio, TX 78259 | Oil & Gas Operator | Dec 2025 |
| 295 | Prevail Energy, Inc | Corpus Chrsti, TX 78469 | Oil & Gas Operator | Dec 2025 |
| 296 | Prime Operating Company | Houston, TX 77024 | Oil & Gas Operator | Dec 2025 |
| 297 | Prize Operating Company | Grapevine, TX 76051 | Oil & Gas Operator | Aug 2016 |
| 298 | Proline Energy Resources Inc | Sugar Land, TX 77479 | Oil & Gas Operator | Dec 2025 |
| 299 | Proton Energy, L.L.C. | Houston, TX 77002 | Oil & Gas Operator | Jun 2005 |
| 300 | Raker Resources LLC | Houston, TX 77042 | Oil & Gas Operator | Dec 2025 |