| 401 | Prairie Production | San Antonio, TX 78228 | Oil & Gas Operator | Apr 2024 |
| 402 | Probe Exploration Company | Abilene, TX 79605 | Oil & Gas Operator | Apr 2024 |
| 403 | Proco Operating Co., Inc. | Graford, TX 76449 | Oil & Gas Operator | Apr 2024 |
| 404 | Prospecta Energy Group, Inc. | Brownwood, TX 76801 | Oil Operator | Apr 2024 |
| 405 | Pruitt Engineering & Petro. Co. | Kerrville, TX 78028 | Oil & Gas Operator | Jul 2007 |
| 406 | Putnam Oil Production | Abilene, TX 79603 | Oil & Gas Operator | Jun 2002 |
| 407 | PV Oil Services, LLC | Abilene, TX 79601 | Oil & Gas Operator | Apr 2024 |
| 408 | Quantum Investments | Lubbock, TX 79424 | Oil Operator | Apr 2024 |
| 409 | Quinlan Engineering | Wichita Falls, TX 76307 | Oil & Gas Operator | Apr 2024 |
| 410 | R & B Energy Co. | Ranger, TX 76470 | Oil & Gas Operator | Mar 2008 |
| 411 | R R Operation Inc | Cross Plains, TX 76443 | Oil & Gas Operator | Apr 2004 |
| 412 | Rainbow Resources, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Aug 2007 |
| 413 | Rainbow Seven Oil & Gas, Inc. | Ranger, TX 76470 | Oil & Gas Operator | Apr 2024 |
| 414 | Red Gap Oil & Gas LLC | Cisco, TX 76437 | Oil & Gas Operator | Apr 2024 |
| 415 | Regal Operating | Cisco, TX 76437 | Oil & Gas Operator | Mar 2008 |
| 416 | Regency Petroleum Co. | Irving, TX 75016 | Oil & Gas Operator | Aug 2002 |
| 417 | Regency Petroleum Co. Of New Mex | Coppell, TX 75019 | Oil & Gas Operator | Apr 2008 |
| 418 | Reh Oil And Gas, LLC. | Pratt, KS 67124 | Oil & Gas Operator | Apr 2019 |
| 419 | Remuda Operating Company | Midland, TX 79711 | Oil & Gas Operator | Apr 2024 |
| 420 | Reo Operating LLC | Austin, TX 78747 | Oil & Gas Operator | Apr 2024 |
| 421 | Rhodes Drilling Company | Abilene, TX 79608 | Oil & Gas Operator | Sep 2000 |
| 422 | Rhonda Operating Company | Midland, TX 79710 | Oil & Gas Operator | Aug 2017 |
| 423 | Rhyne, J.V. | Cisco, TX 76437 | Oil & Gas Operator | Apr 2024 |
| 424 | Richey, Ray Management Co., Inc. | Fort Worth, TX 76108 | Oil & Gas Operator | Apr 2024 |
| 425 | Ridge Oil Company | Breckenridge, TX 76424 | Oil & Gas Operator | Apr 2024 |
| 426 | Ridgeway Exco, Inc. | San Antonio, TX 78279 | Oil & Gas Operator | Mar 1996 |
| 427 | Rife Energy Operating, Inc. | Fort Worth, TX 76106 | Oil & Gas Operator | Apr 2024 |
| 428 | Rife Oil Properties Inc | Fort Worth, TX 76107 | Oil & Gas Operator | Apr 2024 |
| 429 | Rife, M. O., Jr. | Fort Worth, TX 76107 | Oil & Gas Operator | Dec 1998 |
| 430 | Ringo Rig LLC | Coleman, TX 76834 | Oil & Gas Operator | Apr 2024 |
| 431 | Rister Oil&Gas International LLC | Eastland, TX 76448 | Oil & Gas Operator | Apr 2024 |
| 432 | Rister, Dewey | Avoca, TX 79503 | Oil & Gas Operator | Apr 2024 |
| 433 | RJKB Foster Operating LLC | New Braunfels, TX 78132 | Oil & Gas Operator | Apr 2024 |
| 434 | Robertson, T. L. Operating Co. | Cross Plains, TX 76443 | Oil & Gas Operator | May 2004 |
| 435 | Robinson Oil & Gas, Inc. | Chico, TX 76431 | Oil & Gas Operator | Aug 2003 |
| 436 | Robinson Operating Company | Abilene, TX 79604 | Oil & Gas Operator | Aug 2012 |
| 437 | Robinson, Irvin | Abilene, TX 79608 | Oil & Gas Operator | May 1999 |
| 438 | Rock Operating | Abilene, TX 79608 | Oil & Gas Operator | Apr 2024 |
| 439 | Rodman Petroleum Corp. | Odessa, TX 79768 | Oil & Gas Operator | Jul 2023 |
| 440 | Roemer Oil Company | Denver, CO 80202 | Oil & Gas Operator | Nov 1998 |
| 441 | Rollo Resources, LLC | Granbury, TX 76049 | Gas Operator | Apr 2024 |
| 442 | Ronning Gas And Oil LLC | Mesa, AZ 85203 | Oil & Gas Operator | Apr 2024 |
| 443 | Ross Engineering, Inc. | Abilene, TX 79601 | Oil & Gas Operator | Apr 2024 |
| 444 | Roxanna Oil Company | Oklahoma City, OK 73120-2717 | Oil Operator | Aug 2016 |
| 445 | RSD Minerals LLC | Wichita, KS 67206 | Oil Operator | Nov 2023 |
| 446 | S & J Operating Company | Wichita Falls, TX 76301 | Oil & Gas Operator | Mar 2015 |
| 447 | S & V Operating | Zephyr, TX 76890 | Oil & Gas Operator | Apr 2024 |
| 448 | S.B. Street Operating, Inc. | Graham, TX 76450 | Oil & Gas Operator | Apr 2024 |
| 449 | Sabre Oil And Gas Corp. | Houston, TX 77063 | Oil & Gas Operator | Apr 2024 |
| 450 | Sams Energy, Inc. | Abilene, TX 79604 | Oil & Gas Operator | May 1998 |
| 451 | SBS Oil Company | Austin, TX 78749 | Oil & Gas Operator | Apr 2024 |
| 452 | Schkade Bros. Operating Company | Abilene, TX 79604 | Oil & Gas Operator | Oct 2021 |
| 453 | Schkade Production Co. | Abilene, TX 79604 | Oil & Gas Operator | Jul 2020 |
| 454 | Schkade, Carl E. | Albany, TX 76430 | Oil & Gas Operator | Sep 2009 |
| 455 | Schkade, Louis | Albany, TX 76430 | Oil & Gas Operator | Mar 2008 |
| 456 | Scope Operating Company | Fort Worth, TX 76102 | Oil & Gas Operator | Apr 2009 |
| 457 | Scranton Exploration | Eastland, TX 76448 | Oil & Gas Operator | Apr 2024 |
| 458 | Selous Energy, LLC | Fort Worth, TX 76109 | Oil & Gas Operator | Jul 2015 |
| 459 | Sequoia Energy Resources | Dallas, TX 75207 | Oil & Gas Operator | Apr 2024 |
| 460 | Sequoia Fossil Fuels, Inc. | Albany, TX 76430 | Oil & Gas Operator | Apr 2024 |
| 461 | Sequoia Natural Gas, Inc. | Albany, TX 76430 | Oil & Gas Operator | Apr 2024 |
| 462 | Seven Cross Operating, LLC | Santa Anna, TX 76878 | Oil & Gas Operator | Apr 2024 |
| 463 | Shaida, John H. | Wichita, KS 67226 | Oil & Gas Operator | Apr 2024 |
| 464 | Sherman, L. B. | Early, TX 76803 | Oil & Gas Operator | Jun 1998 |
| 465 | Shoshone Oil Company | Dallas, TX 75244 | Oil & Gas Operator | May 1994 |
| 466 | Sierra Oil Company | Fort Worth, TX 76106 | Oil & Gas Operator | Apr 2024 |
| 467 | Simpson Oil & Land Co. | Fort Worth, TX 76102 | Oil & Gas Operator | Apr 2024 |
| 468 | Simpson Operating Services, LP | Ballinger, TX 76821 | Oil & Gas Operator | Apr 2024 |
| 469 | Sinclair Energy Corporation | Fort Worth, TX 76177 | Oil & Gas Operator | Apr 2024 |
| 470 | Skybridge Energy LLC | Jacksboro, TX 76458 | Oil & Gas Operator | Apr 2024 |
| 471 | Sledge, H. G., Inc. | Midland, TX 79701 | Oil & Gas Operator | Dec 2016 |
| 472 | Smalley, Bill | Albany, TX 76430 | Oil & Gas Operator | Jul 2001 |
| 473 | Smith Pipe Of Abilene | Abilene, TX 79608 | Oil & Gas Operator | Apr 2024 |
| 474 | Snow Operating Co., Inc. | Haltom City, TX 76117 | Oil & Gas Operator | Feb 2024 |
| 475 | Snyder Drilling Corp. | Albany, TX 76430 | Oil & Gas Operator | Apr 2024 |
| 476 | So Operating Company | Cisco, TX 76437 | Oil & Gas Operator | Apr 2024 |
| 477 | Southeastern Resources Corp. | Mansfield, TX 76063 | Oil & Gas Operator | Feb 2004 |
| 478 | Southwest Gas Systems, Inc. | Spring, TX 77379 | Oil & Gas Operator | Apr 2024 |
| 479 | Spindletop Oil & Gas Co. | Dallas, TX 75230 | Oil & Gas Operator | Apr 2024 |
| 480 | Square One Energy, Inc. | Tulsa, OK 74159 | Oil & Gas Operator | Oct 2015 |
| 481 | Squyres Oil Co., Inc. | Breckenridge, TX 76424 | Oil & Gas Operator | Apr 2024 |
| 482 | SRG Oil Corporation | Abilene, TX 79604 | Oil & Gas Operator | Apr 1994 |
| 483 | SSC, Inc. | Lubbock, TX 79408 | Oil & Gas Operator | Apr 2024 |
| 484 | St. Johns Operating #1 L.P. | Houston, TX 77060 | Oil & Gas Operator | Aug 2023 |
| 485 | Stacha, Eddy A. | Rice, TX 75155 | Oil & Gas Operator | Apr 2024 |
| 486 | Star One Energy, Inc. | Fort Worth, TX 76163 | Oil & Gas Operator | May 2012 |
| 487 | Stasney, H. R. & Sons, LTD. | Albany, TX 76430 | Oil & Gas Operator | Apr 2024 |
| 488 | STB Energy Inc. | Tulsa, OK 74105 | Oil & Gas Operator | Jul 2008 |
| 489 | Stealth, Inc. | Cross Plains, TX 76443 | Gas Operator | Mar 1997 |
| 490 | Stellex | De Leon, TX 76444 | Oil & Gas Operator | Apr 2024 |
| 491 | Stephens & Johnson Operating Co. | Wichita Falls, TX 76307 | Oil & Gas Operator | Apr 2024 |
| 492 | Stephenson Oil & Gas, Inc. | Eastland, TX 76448 | Oil & Gas Operator | Sep 1999 |
| 493 | Sterling Oil And Gas | Weatherford, TX 76086 | Oil & Gas Operator | Apr 2024 |
| 494 | Stewart Family Holdings LLC | Weatherford, TX 76087 | Oil & Gas Operator | Apr 2024 |
| 495 | Stewart, James G. | Graham, TX 76450 | Oil & Gas Operator | Sep 2019 |
| 496 | Stober Oil And Gas Services, LLC | Breckenridge, TX 76424 | Oil & Gas Operator | Apr 2024 |
| 497 | Stovall, Howard | Cisco, TX 76437 | Oil & Gas Operator | Apr 2024 |
| 498 | Stowe Energy, Inc. | Vernon, TX 76384 | Oil & Gas Operator | Mar 2003 |
| 499 | Stream Energy, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Dec 2023 |
| 500 | Subsurface Energy Corp. | Coleman, TX 76834 | Oil & Gas Operator | Apr 2024 |