| 201 | Hurley Petroleum Corporation | Baton Rouge, LA 70821 | Oil & Gas Operator | Feb 2000 |
| 202 | Hydrocarbon Management, Inc. | San Antonio, TX 78216 | Oil & Gas Operator | Dec 1996 |
| 203 | Imperial Oil Company | Houston, TX 77073 | Oil & Gas Operator | Oct 2004 |
| 204 | Inexco Oil Company | Houston, TX 77210 | Oil & Gas Operator | Mar 2013 |
| 205 | Ipact | Austin, TX 78734 | Oil & Gas Operator | May 2025 |
| 206 | Island Exploration | Houston, TX 77058 | Oil & Gas Operator | May 2025 |
| 207 | J & L Partners | Dallas, TX 75370 | Oil & Gas Operator | Dec 2005 |
| 208 | J.R. Oil And Gas Inc. | Alvin, TX 77511 | Oil & Gas Operator | May 2025 |
| 209 | Jay Management Company LLC | Houston, TX 77057 | Oil & Gas Operator | May 2025 |
| 210 | Jet Oil Producers, Inc. | Coldspring, TX 77331 | Oil & Gas Operator | May 2025 |
| 211 | Jil Oil Corp. | San Antonio, TX 78279 | Oil & Gas Operator | May 2025 |
| 212 | JMC Resources Corp. | Houston, TX 77077 | Oil & Gas Operator | May 2025 |
| 213 | Joy Resources, Inc. | Houston, TX 77027 | Oil & Gas Operator | May 2025 |
| 214 | K-B Exploration Co. | Houston, TX 77057 | Oil & Gas Operator | May 2025 |
| 215 | K.M.A. Operating, Inc. | Graham, TX 76450 | Oil & Gas Operator | Aug 2003 |
| 216 | Kaiser-Francis Oil Company | Tulsa, OK 74121 | Oil & Gas Operator | May 2025 |
| 217 | Kansas Oil & Gas Corporation | Woodland HLS, CA 91367 | Oil & Gas Operator | Feb 2001 |
| 218 | Kelt Oil & Gas, Inc. | Torrance, CA 90503 | Oil & Gas Operator | Dec 2003 |
| 219 | Ken Petroleum Corporation | Dallas, TX 75206 | Oil & Gas Operator | Feb 2019 |
| 220 | Kerns Petroleum, Inc. | San Antonio, TX 78257 | Oil & Gas Operator | Sep 2013 |
| 221 | Kerr-McGee Corporation | Dallas, TX 75380 | Oil & Gas Operator | Mar 2025 |
| 222 | Kerr-McGee Oil & Gas Onshore LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2017 |
| 223 | Kerr-McGee Oil & Gas Onshore LP | Houston, TX 77046 | Oil & Gas Operator | May 2025 |
| 224 | Kerr-McGee Rocky Mountain Corp | Denver, CO 80202 | Oil & Gas Operator | Jan 2007 |
| 225 | Kestrel Resources, Inc. | Dallas, TX 75204 | Oil & Gas Operator | Jan 2017 |
| 226 | Kinder Morgan Tejas Pipeline LLC | Houston, TX 77002 | Oil & Gas Operator | May 2025 |
| 227 | King Oil & Resources Co | Midland, TX 79705 | Oil & Gas Operator | May 2025 |
| 228 | King Operating Corporation | Fort Worth, TX 76147 | Oil & Gas Operator | May 2025 |
| 229 | Kingwood Exploration LLC | Shreveport, LA 71105 | Oil & Gas Operator | May 2025 |
| 230 | Lacy, F. B. Inc. | Houston, TX 77055 | Oil & Gas Operator | Sep 1997 |
| 231 | Lapis Operating, Inc. | Houston, TX 77042 | Oil & Gas Operator | Jul 2015 |
| 232 | Latex Petroleum Corp. | Houston, TX 77090 | Oil & Gas Operator | Aug 2012 |
| 233 | Layton Energy Inc. | Houston, TX 77027 | Oil & Gas Operator | May 2025 |
| 234 | Likover Oil Company | Houston, TX 77024 | Oil & Gas Operator | Mar 2005 |
| 235 | Linan Oil & Gas, Inc. | Houston, TX 77024 | Oil & Gas Operator | May 2025 |
| 236 | Linc Gulf Coast Petroleum, Inc. | Katy, TX 77494 | Oil & Gas Operator | May 2025 |
| 237 | Live Oak Gas Company | Dallas, TX 75251 | Oil & Gas Operator | May 2025 |
| 238 | Llog Exploration Texas, L.P. | Covington, LA 70433 | Oil & Gas Operator | May 2025 |
| 239 | Llox, L.L.C. | Covington, LA 70433 | Oil & Gas Operator | May 2025 |
| 240 | Lomak Production Company | Fort Worth, TX 76102 | Oil & Gas Operator | Aug 1998 |
| 241 | Louisiana Land & Exploration Co. | Houston, TX 77210 | Oil & Gas Operator | Sep 2013 |
| 242 | M & R Exploration Company | Houston, TX 77074 | Oil & Gas Operator | Aug 2003 |
| 243 | Magnum Engineering Company | Corpus Chrsti, TX 78401 | Oil & Gas Operator | May 2025 |
| 244 | Magnum Producing & Operating Co. | Corpus Chrsti, TX 78471 | Oil & Gas Operator | Jan 2004 |
| 245 | Magnum Producing, LP | Corpus Chrsti, TX 78401 | Oil & Gas Operator | May 2025 |
| 246 | Maralo, Inc. | Midland, TX 79702 | Oil & Gas Operator | Dec 1998 |
| 247 | Marlin Energy Southwest GP, LLC | Lafayette, LA 70503 | Oil & Gas Operator | May 2025 |
| 248 | Masters Oil & Gas, LLC | Houston, TX 77079 | Oil & Gas Operator | May 2025 |
| 249 | Masters Resources, L.L.C. | Houston, TX 77079 | Oil & Gas Operator | Dec 2008 |
| 250 | Maverick Drilling Co., Inc. | Austin, TX 78729 | Oil & Gas Operator | Mar 2015 |
| 251 | Maxim Energy Corporation | Baytown, TX 77520 | Oil & Gas Operator | Feb 2025 |
| 252 | McCarter, A. Nelson | Houston, TX 77063 | Oil & Gas Operator | Aug 2003 |
| 253 | McGowan Working Partners | Jackson, MS 39296 | Oil & Gas Operator | Dec 2000 |
| 254 | McGowan Working Partners, Inc. | Jackson, MS 39296 | Oil & Gas Operator | May 2025 |
| 255 | McGowen Resources Co., Inc. | Dallas, TX 75206 | Oil & Gas Operator | Aug 2003 |
| 256 | Meridian Resource & Expl LLC,The | Houston, TX 77094 | Oil & Gas Operator | Nov 2012 |
| 257 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | May 2025 |
| 258 | MGF Oil Corporation | Tulsa, OK 74121 | Oil & Gas Operator | Jun 1998 |
| 259 | Middleton Oil Company | Houston, TX 77006 | Oil & Gas Operator | May 2025 |
| 260 | Midpar L.P. | Midland, TX 79702 | Oil & Gas Operator | Feb 1995 |
| 261 | Milagro Exploration, LLC | Houston, TX 77010 | Oil & Gas Operator | Aug 2018 |
| 262 | Miller, Bob I. | Abilene, TX 79604 | Oil & Gas Operator | Mar 2008 |
| 263 | Minexprod LLC | Katy, TX 77494 | Oil Operator | May 2025 |
| 264 | Mitchell Energy Corp | Houston, TX 77002 | Oil & Gas Operator | Aug 2013 |
| 265 | MJ Oil, Inc. | Houston, TX 77265 | Oil & Gas Operator | May 2025 |
| 266 | Mobil Producing TX. & N.M. Inc. | Spring, TX 77389 | Oil & Gas Operator | May 2025 |
| 267 | Mortimer Exploration Company | San Antonio, TX 78209 | Oil & Gas Operator | Sep 2003 |
| 268 | Mosbacher Energy Company | Houston, TX 77002 | Oil & Gas Operator | May 2025 |
| 269 | Mueller Exploration, Inc. | Portland, TX 78374 | Oil & Gas Operator | May 2025 |
| 270 | MW Petroleum Corporation | Houston, TX 77056 | Oil & Gas Operator | Mar 2015 |
| 271 | National Offshore LP | Oklahoma City, OK 73154 | Oil & Gas Operator | Mar 2008 |
| 272 | National Onshore LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2008 |
| 273 | Nei Production, Inc. | Nichols Hill, OK 73116 | Oil & Gas Operator | May 2025 |
| 274 | New Century Exploration, Inc. | Spring, TX 77379 | Oil & Gas Operator | May 2025 |
| 275 | New Horizon Resources LLC | Houston, TX 77057 | Oil & Gas Operator | May 2025 |
| 276 | Newfield Exploration Company | The Woodlands, TX 77380 | Oil & Gas Operator | Jun 2017 |
| 277 | Newton Corp.,The | Dallas, TX 75251 | Oil & Gas Operator | May 2025 |
| 278 | Nicor Exploration Company | Houston, TX 77002 | Oil & Gas Operator | Jun 1993 |
| 279 | Nicor Production Company | Houston, TX 77002 | Oil & Gas Operator | May 1993 |
| 280 | Noble Energy Inc | Midland, TX 79706 | Oil & Gas Operator | May 2025 |
| 281 | Nordstrand Engineering Inc | Houston, TX 77019 | Oil & Gas Operator | May 2025 |
| 282 | North Central Oil Corp | Houston, TX 77252 | Oil & Gas Operator | Dec 2005 |
| 283 | North Lake Resources LLC | Oklahoma City, OK 73132 | Oil & Gas Operator | May 2025 |
| 284 | O'Sullivan Oil & Gas Co., Inc. | Houston, TX 77002 | Oil & Gas Operator | Oct 2000 |
| 285 | Odum Oil & Gas Co. | Harper, TX 78631 | Oil & Gas Operator | May 2025 |
| 286 | Oil Coast Corp. | S Houston, TX 77587 | Oil & Gas Operator | May 2025 |
| 287 | Oil Lease Operating Co. | Coldspring, TX 77331 | Oil & Gas Operator | Aug 2003 |
| 288 | Oil Well Buyers Corp. | Houston, TX 77056 | Oil & Gas Operator | Dec 2024 |
| 289 | Onshore Royalties LLC | Houston, TX 77269 | Oil & Gas Operator | Mar 2025 |
| 290 | Oryx Energy Company | Dallas, TX 75221 | Oil & Gas Operator | May 2002 |
| 291 | Osyka Producing Company, Inc. | Houston, TX 77242 | Oil & Gas Operator | May 2025 |
| 292 | Otex Resources LLC | Baytown, TX 77520 | Oil & Gas Operator | May 2025 |
| 293 | Oxy USA Inc | Houston, TX 77046 | Oil & Gas Operator | May 2025 |
| 294 | Padon, Frank B. Oil Oper., Inc. | Houston, TX 77227 | Oil & Gas Operator | Nov 1998 |
| 295 | Palace Operating Company | Tulsa, OK 74136 | Oil & Gas Operator | Aug 2009 |
| 296 | Palisades Operating Company | Midland, TX 79702 | Oil & Gas Operator | May 2025 |
| 297 | Panaco Production Co | Houston, TX 77002 | Oil & Gas Operator | Dec 1999 |
| 298 | Panaco, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2024 |
| 299 | Panther Creek Resources, LLC | Denver, CO 80202 | Oil & Gas Operator | May 2012 |
| 300 | Papco, Inc. | Warren, PA 16365 | Oil & Gas Operator | May 2025 |