| 301 | Global Natural Resources Corp. | Houston, TX 77002 | Oil & Gas Operator | May 1998 |
| 302 | GMT Energy Corporation | Houston, TX 77042 | Oil & Gas Operator | Feb 2005 |
| 303 | GMT Exploration Co Texas, LLC | Houston, TX 77070 | Oil & Gas Operator | Jun 2014 |
| 304 | GMT Inc. | Houston, TX 77042 | Oil & Gas Operator | Jan 2003 |
| 305 | Goforth Production Company | Rockdale, TX 76567 | Oil Operator | Feb 2014 |
| 306 | Goldsmith Operating, LLC | Tyler, TX 75711 | Oil & Gas Operator | May 2025 |
| 307 | Goldsmith, J. Paul | Tyler, TX 75711 | Oil & Gas Operator | Feb 1997 |
| 308 | Goodrich Petroleum Company | Houston, TX 77002 | Oil & Gas Operator | Feb 2022 |
| 309 | Grace Petroleum Corp. | Tulsa, OK 74103 | Oil & Gas Operator | Oct 1997 |
| 310 | Granite Oil Company | Austin, TX 78716 | Oil & Gas Operator | Nov 2000 |
| 311 | Graward Operating, Inc. | Tyler, TX 75702 | Oil & Gas Operator | May 2025 |
| 312 | Graystone Energy Corporation | Judson, TX 75660 | Oil & Gas Operator | May 2025 |
| 313 | Green River Resources Inc. | Keystone, CO 80435 | Oil & Gas Operator | May 2025 |
| 314 | Gregg Operating, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | May 2025 |
| 315 | Greystone Oil & Gas, LLP | Houston, TX 77057 | Oil & Gas Operator | Dec 2015 |
| 316 | Gruy Petroleum Management Co. | Irving, TX 75014 | Oil & Gas Operator | Nov 2014 |
| 317 | Guest Petroleum Incorporated | Edmond, OK 73013 | Oil & Gas Operator | Mar 2025 |
| 318 | Gulf States Petro. Corp. | Dallas, TX 75202 | Oil & Gas Operator | Apr 2006 |
| 319 | Gulfport Oil & Gas Inc. | Gulfport, MS 39501 | Oil & Gas Operator | May 2025 |
| 320 | H & T Exploration, Inc. | Longview, TX 75605 | Oil & Gas Operator | May 2025 |
| 321 | Halcon Resources Operating, Inc. | Tulsa, OK 74135 | Oil & Gas Operator | Dec 2013 |
| 322 | Hallwood Petroleum, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jan 2025 |
| 323 | Halo Energy L.L.C. | Kilgore, TX 75662 | Oil Operator | May 2025 |
| 324 | Hamon Operating Company | Dallas, TX 75201 | Oil & Gas Operator | Dec 2011 |
| 325 | Harbor Resources LLC | Oklahoma City, OK 73120 | Oil & Gas Operator | May 2025 |
| 326 | Hardy Ranch, Inc. | Henderson, TX 75654 | Oil & Gas Operator | May 2025 |
| 327 | Harleton Oil & Gas Inc. | Tyler, TX 75710 | Oil & Gas Operator | May 2025 |
| 328 | Harman Operating Company, Inc. | Tyler, TX 75702 | Oil & Gas Operator | Dec 2007 |
| 329 | Hawkins Oil & Gas Inc | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2016 |
| 330 | Headington Oil Company | Dallas, TX 75231 | Oil & Gas Operator | Dec 2016 |
| 331 | Hec Petroleum, Inc | Midland, TX 79705 | Oil & Gas Operator | Mar 2006 |
| 332 | Heritage Energy Corporation | Waco, TX 76710 | Oil & Gas Operator | Sep 2004 |
| 333 | Herv Oil, LLC | Oklahoma City, OK 73116 | Oil Operator | Mar 2025 |
| 334 | Hess Corporation | Houston, TX 77010 | Oil & Gas Operator | Aug 2017 |
| 335 | Hibbard Energy, LP | Whitehouse, TX 75791 | Oil & Gas Operator | May 2025 |
| 336 | Highmark Energy Operating, LLC | Dallas, TX 75222 | Oil & Gas Operator | May 2025 |
| 337 | Hightower Exploration | Kilgore, TX 75662 | Oil & Gas Operator | May 2025 |
| 338 | Hilcorp Energy Company | Houston, TX 77208 | Oil & Gas Operator | May 2025 |
| 339 | Hill Production Company | Kilgore, TX 75663 | Oil & Gas Operator | Feb 2009 |
| 340 | Hillin-Simon Oil Company | Houston, TX 77079 | Oil & Gas Operator | Mar 2013 |
| 341 | Hinton Production Company | MT Pleasant, TX 75455 | Oil & Gas Operator | Aug 1995 |
| 342 | Hodge T F | Fort Worth, TX 76102 | Oil & Gas Operator | Apr 2007 |
| 343 | Holt Oil And Cattle LLC | Bedias, TX 77831 | Oil & Gas Operator | May 2025 |
| 344 | Hombre Oil Co., LTD. | Tyler, TX 75713 | Oil & Gas Operator | Apr 2021 |
| 345 | Hopkins, T. M. Operating Co. | Kilgore, TX 75663 | Oil & Gas Operator | May 2025 |
| 346 | Houston Exploration Co, The | Houston, TX 77002 | Oil & Gas Operator | Apr 2017 |
| 347 | Houston Oil & Minerals Corp. | Houston, TX 77002 | Oil & Gas Operator | Aug 1996 |
| 348 | Howell & Sandlin, Inc. | Marshall, TX 75671 | Oil & Gas Operator | Jan 2001 |
| 349 | Howell Oil & Gas, Inc. | Marshall, TX 75671 | Oil & Gas Operator | Oct 2019 |
| 350 | HRB Operating Company, Inc. | Bridgeport, TX 76426 | Oil & Gas Operator | May 2025 |
| 351 | Hrubetz Operating Company | Dallas, TX 75225 | Oil & Gas Operator | Feb 1999 |
| 352 | Hughey, Gaylord T. SR. Oper. Co. | Tyler, TX 75711 | Oil & Gas Operator | Feb 1998 |
| 353 | Hughey, W. R., Operating Co. | Tyler, TX 75711 | Oil & Gas Operator | Feb 2005 |
| 354 | Hugus Investment Company, Inc. | Tyler, TX 75711 | Oil & Gas Operator | May 2025 |
| 355 | Hunt Oil Company | Dallas, TX 75201 | Oil & Gas Operator | May 2025 |
| 356 | Hunt Petroleum Corporation | Dallas, TX 75201 | Oil & Gas Operator | Nov 2008 |
| 357 | Hunt, WM. Herbert, Trust Est. | Dallas, TX 75201 | Oil & Gas Operator | Sep 1998 |
| 358 | Huntington Resources Inc | Tulsa, OK 74103 | Oil & Gas Operator | Oct 2006 |
| 359 | Hydrocarbon Lease Management LTD | Addison, TX 75001 | Oil & Gas Operator | Jul 2002 |
| 360 | Hydrogeo, L.L.C. | Houston, TX 77074 | Oil & Gas Operator | May 2025 |
| 361 | Imagery Exploration, Inc. | Dallas, TX 75380 | Oil & Gas Operator | May 2025 |
| 362 | Indigo Minerals LLC | Houston, TX 77002 | Oil & Gas Operator | Sep 2022 |
| 363 | International Western Oil Corp | Weatherford, TX 76086 | Oil & Gas Operator | May 2025 |
| 364 | Ironhorse Operations, LLC | Kilgore, TX 75663 | Oil Operator | May 2025 |
| 365 | Ironwood Oil & Gas LLC | Houston, TX 77067 | Oil & Gas Operator | Jun 2014 |
| 366 | J-Car Operating, Inc. | Lindale, TX 75771 | Oil & Gas Operator | Mar 1997 |
| 367 | J-O'B Operating Company | Shreveport, LA 71135 | Oil & Gas Operator | May 2025 |
| 368 | Jackson, Jeral W. Inc. | Wichita Falls, TX 76307 | Oil & Gas Operator | May 2004 |
| 369 | Jamex, Inc. | Lewisville, TX 75067 | Oil & Gas Operator | May 2025 |
| 370 | Jandar Exploration, L. C. | Tyler, TX 75703 | Oil & Gas Operator | May 2025 |
| 371 | Jess Energy Company | Tyler, TX 75710 | Oil & Gas Operator | Sep 1997 |
| 372 | Jet Production Company | Kilgore, TX 75663 | Oil & Gas Operator | Jun 2002 |
| 373 | John P. Bogdanich Operating, LLC | Kilgore, TX 75663 | Oil Operator | May 2025 |
| 374 | Jordan Properties | Kilgore, TX 75663 | Oil & Gas Operator | Aug 2003 |
| 375 | Josey, Lenoir M., Inc. | Houston, TX 77019 | Oil & Gas Operator | Aug 2003 |
| 376 | Joy Resources, Inc. | Houston, TX 77027 | Oil & Gas Operator | May 2025 |
| 377 | Jurassic Exploration, Inc. | Longview, TX 75601 | Oil & Gas Operator | May 2025 |
| 378 | K Me Company, LLC | Kilgore, TX 75663 | Oil Operator | May 2025 |
| 379 | Kabco Oil & Gas Company | Longview, TX 75604 | Oil & Gas Operator | Jun 2018 |
| 380 | Kaiser-Francis Oil Company | Tulsa, OK 74121 | Oil & Gas Operator | May 2025 |
| 381 | Kalos Corporation | Tyler, TX 75701 | Oil & Gas Operator | May 2025 |
| 382 | Karper Oil & Gas Corporation | Graham, TX 76450 | Oil & Gas Operator | May 2025 |
| 383 | Katy Resources Etx, LLC | Shreveport, LA 71101 | Oil & Gas Operator | Mar 2011 |
| 384 | Katy Resources LLC | Arlington, TX 76016 | Oil & Gas Operator | May 2025 |
| 385 | KCM Management, Inc. | Dallas, TX 75230 | Oil & Gas Operator | Oct 2014 |
| 386 | Keith Petroleum Corporation | Houston, TX 77063 | Oil & Gas Operator | Jan 1993 |
| 387 | Kepa Energy, L.C. | Marshall, TX 75670 | Oil & Gas Operator | Mar 1998 |
| 388 | Kerr-McGee Corporation | Dallas, TX 75380 | Oil & Gas Operator | Mar 2025 |
| 389 | Kerr-McGee Oil & Gas Onshore LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2017 |
| 390 | Kestrel Resources, Inc. | Dallas, TX 75204 | Oil & Gas Operator | Jan 2017 |
| 391 | Key Production Company, Inc. | Longview, TX 75606 | Oil & Gas Operator | Mar 2025 |
| 392 | Keyway Oil & Gas Operating LLC | Kilgore, TX 75663 | Oil Operator | Oct 2020 |
| 393 | Kimbell Operating Company | Fort Worth, TX 76102 | Oil & Gas Operator | May 2025 |
| 394 | Kinder Morgan Production Co LLC | Midland, TX 79705 | Oil & Gas Operator | May 2025 |
| 395 | King Operating Corporation | Fort Worth, TX 76147 | Oil & Gas Operator | May 2025 |
| 396 | Kingwood Resources, Inc. | Kingwood, TX 77339 | Oil & Gas Operator | May 2022 |
| 397 | Kiva Resources Inc. | Houston, TX 77265 | Oil & Gas Operator | Mar 2008 |
| 398 | KJ Energy, LLC | MT Enterprise, TX 75681 | Oil & Gas Operator | Jul 2024 |
| 399 | Klo Oil & Gas, L.L.C. | Tulsa, OK 74120 | Oil & Gas Operator | Jan 2023 |
| 400 | L & R Energy Corporation | Spearman, TX 79081 | Oil & Gas Operator | Nov 2014 |