| 401 | Shearer Oil Company | Graham, TX 76450 | Oil & Gas Operator | May 2002 |
| 402 | Shed Oil Company | Electra, TX 76360 | Oil Operator | Sep 2025 |
| 403 | Sheer Energy, LLC | Kilgore, TX 75663 | Oil & Gas Operator | Sep 2025 |
| 404 | Sheets Exploration Co., Inc. | Breckenridge, TX 76424 | Oil & Gas Operator | Jul 2016 |
| 405 | Sheets, P. A. | Breckenridge, TX 76424 | Oil & Gas Operator | Jun 1994 |
| 406 | Shefts & Shefts, Inc. | Luling, TX 78648 | Oil & Gas Operator | Sep 2025 |
| 407 | Shelby Boswell Operator, LLC | Dallas, TX 75225 | Oil & Gas Operator | Sep 2025 |
| 408 | Shelby Operating Company | Dallas, TX 75205 | Oil & Gas Operator | Sep 2025 |
| 409 | Shelby Operating, Inc. | Flower Mound, TX 75028 | Oil & Gas Operator | Jul 1997 |
| 410 | Shelby Production Co. | Kilgore, TX 75663 | Oil & Gas Operator | Mar 2009 |
| 411 | Shelby Production, Inc. | Kilgore, TX 75663 | Gas Operator | Sep 2025 |
| 412 | Shelby, Michael H. | Shreveport, LA 71101 | Oil & Gas Operator | Sep 2025 |
| 413 | Shelco | Maysville, MO 64469 | Oil & Gas Operator | May 2021 |
| 414 | Sheldon Resources, L.P. | Bryan, TX 77805 | Oil & Gas Operator | Sep 2025 |
| 415 | Shell Frontier Oil & Gas Inc. | Houston, TX 77001 | Oil & Gas Operator | Feb 1997 |
| 416 | Shell Land & Energy Co. | Houston, TX 77001 | Oil & Gas Operator | Feb 1997 |
| 417 | Shell Offshore Inc. | New Orleans, LA 70161 | Oil & Gas Operator | Jan 2008 |
| 418 | Shell Onshore Ventures Inc | Houston, TX 77210 | Gas Operator | Jun 2002 |
| 419 | Shell Western E&P | Houston, TX 77001 | Oil & Gas Operator | Sep 2025 |
| 420 | Shell Western E&P Inc. | Houston, TX 77001 | Oil & Gas Operator | May 2011 |
| 421 | Shelley, Richard W | Wichita Falls, TX 76310 | Oil & Gas Operator | Jun 2015 |
| 422 | Shelton, Charles M. | Baytown, TX 77521 | Oil & Gas Operator | Aug 2003 |
| 423 | Shenandoah Oil, Inc. (I) | Midland, TX 79710 | Oil & Gas Operator | Apr 1996 |
| 424 | Shenandoah Petroleum Corporation | Midland, TX 79705 | Oil & Gas Operator | Sep 2025 |
| 425 | Shenandoah Resources LLC | Houston, TX 77086 | Oil & Gas Operator | Apr 2020 |
| 426 | Sheneeda Energy, LLC | O Brien, TX 79539 | Oil Operator | Jun 2025 |
| 427 | Shepperd, William M. | Houston, TX 77279 | Oil & Gas Operator | Sep 2012 |
| 428 | Sheridan Energy,Inc. | Houston, TX 77002 | Oil & Gas Operator | Feb 2000 |
| 429 | Sheridan Production Co III, LLC | Houston, TX 77056 | Oil & Gas Operator | Sep 2025 |
| 430 | Sheridan Production Company, LLC | Houston, TX 77056 | Oil & Gas Operator | May 2025 |
| 431 | Sherley, O. C. | Megargel, TX 76370 | Oil & Gas Operator | Aug 2003 |
| 432 | Sherman Oil Company LLC | Wichita Falls, TX 76308 | Oil Operator | Apr 2025 |
| 433 | Sherman, L. B. | Early, TX 76803 | Oil & Gas Operator | Jun 1998 |
| 434 | Shidler, Mark L., Inc. | Houston, TX 77055 | Oil & Gas Operator | Sep 2025 |
| 435 | Shield Operating Co. | Georgetown, TX 78627 | Oil & Gas Operator | Aug 2003 |
| 436 | Shield Petroleum | College Sta, TX 77845 | Oil & Gas Operator | Sep 2025 |
| 437 | Shifflett Operating Company | Snyder, TX 79550 | Oil & Gas Operator | Sep 2025 |
| 438 | Shiloh Oil Company LLC | Williston, FL 32696 | Oil & Gas Operator | Sep 2025 |
| 439 | Shiner Exploration, LLC | Houston, TX 77091 | Oil & Gas Operator | Sep 2025 |
| 440 | Shines'S Oil Co. | Jacksboro, TX 76458 | Oil & Gas Operator | Oct 2009 |
| 441 | Shinnery Oil Company, Inc. | Midland, TX 79701 | Oil & Gas Operator | Sep 2025 |
| 442 | Shirley, B. J. | Lawn, TX 79530 | Oil & Gas Operator | Mar 2008 |
| 443 | Shivers, Linward, Operator | Shreveport, LA 71161 | Oil & Gas Operator | Sep 1997 |
| 444 | SHL Operating | Lubbock, TX 79416 | Oil & Gas Operator | Sep 2025 |
| 445 | Shoco Production LLC | Kilgore, TX 75663 | Oil & Gas Operator | Sep 2025 |
| 446 | Shoco Production, L.P. | Kilgore, TX 75663 | Oil & Gas Operator | May 2020 |
| 447 | Shootin Star Oil, L.L.C. | Natalia, TX 78059 | Oil Operator | Sep 2025 |
| 448 | Shore Petroleum Corp. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Sep 2025 |
| 449 | Shore Production Co. | Longview, TX 75604 | Oil & Gas Operator | Aug 2005 |
| 450 | Shoreham Oil & Gas Company, Inc. | Katy, TX 77492 | Oil & Gas Operator | Sep 2025 |
| 451 | Shoreline Energy Partners, LLC | Chandler, AZ 85249 | Oil Operator | May 2011 |
| 452 | Shoreline Petroleum Corp. | Channelview, TX 77530 | Oil & Gas Operator | Sep 2003 |
| 453 | Shoreline Production Serv., Inc. | Rockport, TX 78381 | Oil & Gas Operator | Apr 2002 |
| 454 | Short Oil Co. | Luling, TX 78648 | Oil & Gas Operator | May 2025 |
| 455 | Shoshone Oil Company | Dallas, TX 75244 | Oil & Gas Operator | May 1994 |
| 456 | Showdown Energy Corporation | Dallas, TX 75230 | Oil & Gas Operator | Aug 2003 |
| 457 | Showdown Operating, Inc. | Dallas, TX 75230 | Oil & Gas Operator | May 1996 |
| 458 | Showhorn Holding Co., L.L.C. | Normangee, TX 77871 | Oil Operator | Sep 2025 |
| 459 | SHS Operating Company | Shreveport, LA 71149 | Oil & Gas Operator | Jan 2025 |
| 460 | Shubuta Oil Corporation | Houston, TX 77056 | Oil & Gas Operator | Sep 1998 |
| 461 | Shuler Drilling Co., Inc. | El Dorado, AR 71730 | Oil & Gas Operator | Jan 2025 |
| 462 | Shumate, Jess | Brookesmith, TX 76827 | Oil Operator | Jun 2006 |
| 463 | SHWJ Oil & Gas Co., Inc. | Oil City, LA 71061 | Oil Operator | Sep 2025 |
| 464 | Siana Oil & Gas | Conroe, TX 77305 | Oil & Gas Operator | Sep 2025 |
| 465 | Sideline Oil & Gas, L.P. | Friendswood, TX 77549 | Oil Operator | Sep 2025 |
| 466 | Sidwell Oil & Gas, Inc. | Amarillo, TX 79105 | Oil & Gas Operator | Sep 2014 |
| 467 | Sidwell Operating Company, L.P. | Amarillo, TX 79105 | Oil & Gas Operator | Sep 2025 |
| 468 | Siegfried R H Inc | Tulsa, OK 74104 | Oil & Gas Operator | Mar 2008 |
| 469 | Siempre Energy Operating, LLC | Houston, TX 77094 | Oil Operator | Sep 2025 |
| 470 | Sien Operating Company, LLC | San Antonio, TX 78209 | Oil Operator | May 2023 |
| 471 | Sierra Exploration Company | San Antonio, TX 78209 | Oil & Gas Operator | Mar 2008 |
| 472 | Sierra Group, L.L.C. | San Angelo, TX 76904 | Oil & Gas Operator | Jan 2025 |
| 473 | Sierra Lima Oil & Gas, LLC | Abilene, TX 79604 | Oil & Gas Operator | Sep 2025 |
| 474 | Sierra Madre Natural Res., LLC | Dallas, TX 75225 | Oil & Gas Operator | Dec 2016 |
| 475 | Sierra Minerals, Inc. | Rockdale, TX 76567 | Oil & Gas Operator | Sep 2025 |
| 476 | Sierra Oil Company | Fort Worth, TX 76106 | Oil & Gas Operator | Sep 2025 |
| 477 | Sierra Resources, Inc. | Oklahoma City, OK 73142 | Oil & Gas Operator | Jul 2025 |
| 478 | Sierra Resources, LLC | Houston, TX 77219 | Oil & Gas Operator | Aug 2021 |
| 479 | Siete Oil And Gas Corporation | Midland, TX 79702 | Oil & Gas Operator | Aug 2003 |
| 480 | Sigma Energy & Explor., Co LLC | Ozona, TX 76943 | Oil & Gas Operator | Feb 2010 |
| 481 | Sigma Exploration Corp., The | Dallas, TX 75230 | Oil & Gas Operator | Sep 1998 |
| 482 | Sigma Oper & Develop Co., Inc. | Midland, TX 79701 | Oil & Gas Operator | Sep 2025 |
| 483 | Sigmon Construction Co., Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Sep 2025 |
| 484 | Sigmon Production Company, Inc. | Longview, TX 75608 | Oil & Gas Operator | Dec 2013 |
| 485 | Signal Oil And Gas Company | Colleyville, TX 76034 | Oil & Gas Operator | Sep 2025 |
| 486 | Signal Oil Company, LLC | Kilgore, TX 75663 | Oil & Gas Operator | Sep 2025 |
| 487 | Sikes Operating, Inc. | Tyler, TX 75711 | Oil & Gas Operator | Jun 2003 |
| 488 | Sikes, Arlas M. | Brownwood, TX 76801 | Oil & Gas Operator | May 2000 |
| 489 | Siltstone Resources Op II, LLC | Wilmington, DE 19801 | Oil & Gas Operator | Sep 2025 |
| 490 | Silver Anchor Resources LLC | Azle, TX 76020 | Oil & Gas Operator | Sep 2025 |
| 491 | Silver Creek Oil | Merkel, TX 79536 | Oil & Gas Operator | Aug 2003 |
| 492 | Silver Creek Oil & Gas, LLC | Flower Mound, TX 75022 | Oil & Gas Operator | Sep 2025 |
| 493 | Silver Creek Permian Op Co, LLC | Irving, TX 75038 | Oil & Gas Operator | Apr 2023 |
| 494 | Silver Creek Resources, LLC | Irving, TX 75038 | Oil & Gas Operator | Apr 2017 |
| 495 | Silver Fox Oil & Gas LLC | McAllen, TX 78504 | Oil & Gas Operator | Sep 2025 |
| 496 | Silver Hill Energy Operating, LLC | Dallas, TX 75201 | Oil & Gas Operator | Sep 2025 |
| 497 | Silver Hill Energy Partners, LLC | Dallas, TX 75219 | Oil & Gas Operator | Feb 2017 |
| 498 | Silver Oak Energy, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Apr 2016 |
| 499 | Silver Oak Operating, Inc. | Longview, TX 75601 | Oil & Gas Operator | Dec 2009 |
| 500 | Silver Oak Operating, LLC | Longview, TX 75604 | Oil & Gas Operator | Sep 2025 |