| 401 | Northfork Exploration LLC | Electra, TX 76360 | Oil Operator | Mar 2025 |
| 402 | O S & S Oil Company | Electra, TX 76360 | Oil & Gas Operator | Jan 2018 |
| 403 | O'Neal Operating Company | Wichita Falls, TX 76307 | Oil & Gas Operator | Dec 1999 |
| 404 | O'Neil, Pat | Wichita Falls, TX 76308 | Oil & Gas Operator | Nov 2005 |
| 405 | Oklahoma Petroleum Allies LLC | Ardmore, OK 73401 | Oil Operator | Oct 2023 |
| 406 | Onyx Industries LTD, Inc. | Wichita Falls, TX 76308 | Oil & Gas Operator | Aug 2003 |
| 407 | Os&S Operating Inc. | Electra, TX 76360 | Oil & Gas Operator | Mar 2025 |
| 408 | Oscar Oil Company | Iowa Park, TX 76367 | Oil & Gas Operator | Sep 2004 |
| 409 | Owens Oil Company | Iowa Park, TX 76367 | Oil & Gas Operator | Sep 2008 |
| 410 | Oxy USA Inc | Houston, TX 77046 | Oil & Gas Operator | Mar 2025 |
| 411 | Pace And Ray Oil Co. | Electra, TX 76360 | Oil & Gas Operator | Mar 2025 |
| 412 | Pacific Exploration Oper Co, LLC | Houston, TX 77057 | Oil Operator | Mar 2025 |
| 413 | Palmer, James W. | Wichita Falls, TX 76308 | Oil & Gas Operator | Jul 2002 |
| 414 | Palo Petroleum, Inc. | Dallas, TX 75360 | Oil & Gas Operator | Mar 2025 |
| 415 | Panhandle Oil & Gas Inc | Oklahoma City, OK 73112-5688 | Oil & Gas Operator | May 2007 |
| 416 | Parnell Operating | Kamay, TX 76369 | Oil & Gas Operator | Mar 2025 |
| 417 | Parsley, Amos | Wichita Falls, TX 76301 | Oil & Gas Operator | Mar 2008 |
| 418 | Patrick, Joe Ben | Petrolia, TX 76377 | Oil & Gas Operator | Oct 2009 |
| 419 | Patriot Operating Company, Inc. | Houston, TX 77008 | Oil & Gas Operator | Sep 2003 |
| 420 | Patton, Donald L & Jerry | Electra, TX 76360 | Oil & Gas Operator | Aug 2007 |
| 421 | Peba Oil & Gas Co. | Wichita Falls, TX 76302 | Oil & Gas Operator | Jun 2015 |
| 422 | Pecos Country Operating Inc. | N Richlnd HLS, TX 76182 | Oil Operator | Mar 2025 |
| 423 | Pennington, W. L., Inc. | Wichita Falls, TX 76301 | Oil & Gas Operator | Jul 1996 |
| 424 | Petex | Breckenridge, TX 76424 | Oil & Gas Operator | Mar 2025 |
| 425 | PF Operating Company | Wichita Falls, TX 76302 | Oil & Gas Operator | Aug 2003 |
| 426 | Pgi Operating, LLC | Sweetwater, TX 79556 | Oil Operator | Mar 2025 |
| 427 | Phillips 66 Company | Bartlesville, OK 74004 | Oil & Gas Operator | Aug 1997 |
| 428 | Phoenix Oil & Gas | Kyle, TX 78640 | Oil & Gas Operator | Mar 2025 |
| 429 | Phoenix Operating Company, Inc. | Shreveport, LA 71161 | Oil & Gas Operator | Mar 2015 |
| 430 | PKS Energy Savers Inc. | Wichita Falls, TX 76307 | Oil & Gas Operator | Jul 1994 |
| 431 | Plantation Operating Co., Inc. | Holliday, TX 76366 | Oil & Gas Operator | Mar 2025 |
| 432 | Pobres Incorporated | Wichita Falls, TX 76308 | Oil & Gas Operator | Mar 2008 |
| 433 | Poteet Operating Co. | Wichita Falls, TX 76307 | Oil & Gas Operator | Aug 1994 |
| 434 | Prickett Operating Company | Wichita Falls, TX 76302 | Oil & Gas Operator | Mar 2008 |
| 435 | Prickett, Jimmy | Wichita Falls, TX 76308 | Oil Operator | Feb 2002 |
| 436 | Primrose Operating Company | Wichita Falls, TX 76307 | Oil & Gas Operator | Jun 2007 |
| 437 | Prince Properties, Inc. | Electra, TX 76360 | Oil & Gas Operator | Aug 2003 |
| 438 | Pro Oil & Gas Inc | Frankfort, IL 60423 | Oil & Gas Operator | May 2014 |
| 439 | Pro. Energy I Resource, LLC | Haslet, TX 76052 | Oil Operator | Mar 2025 |
| 440 | Pryor Petroleum Corporation | Wichita Falls, TX 76308 | Oil & Gas Operator | Mar 2025 |
| 441 | Pumpco Services | Gainesville, TX 76240 | Oil & Gas Operator | Mar 2008 |
| 442 | Quatro Oil And Gas, Inc. | Wichita Falls, TX 76301 | Oil & Gas Operator | Mar 2025 |
| 443 | R & R Operating | Wichita Falls, TX 76307 | Oil & Gas Operator | Jul 2004 |
| 444 | R2Q Operating LLC | Iowa Park, TX 76367 | Oil & Gas Operator | Mar 2025 |
| 445 | Rajoil Inc. | Vernon, TX 76384 | Oil & Gas Operator | Aug 2003 |
| 446 | Ranphil, LLC | Hiltn Head Is, SC 29928 | Oil & Gas Operator | Feb 2016 |
| 447 | Ray Loveless Enterprises, L.L.C. | Kilgore, TX 75663 | Oil Operator | Mar 2025 |
| 448 | Raymond'S Operating, Inc. | Kamay, TX 76369 | Oil & Gas Operator | Mar 2025 |
| 449 | Red River Crude Oil LLC | Houston, TX 77081 | Oil Operator | Dec 2024 |
| 450 | Red River Operating & DRLG. Co. | Allen, TX 75002 | Oil & Gas Operator | Mar 2025 |
| 451 | Redwood Operating, Inc. | Houston, TX 77058 | Oil & Gas Operator | Mar 2025 |
| 452 | Reed, Trace | Bridgeport, TX 76426 | Oil & Gas Operator | Mar 2025 |
| 453 | Renaissance Petroleum Co LLC | Houston, TX 77058 | Oil & Gas Operator | Nov 2011 |
| 454 | Reo Operating LLC | Austin, TX 78747 | Oil & Gas Operator | Mar 2025 |
| 455 | Reynolds, J. C. & W. F. | Wichita Falls, TX 76301 | Oil & Gas Operator | Mar 2025 |
| 456 | Ric Petroleum, Inc. | Wichita Falls, TX 76307 | Oil & Gas Operator | Aug 2003 |
| 457 | Ro-Jo, Inc. | Highland VLG, TX 75077 | Oil & Gas Operator | Aug 2003 |
| 458 | Roberts & Hammack, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2025 |
| 459 | Robertson, Gene Oil Co. | Burkburnett, TX 76354 | Oil & Gas Operator | Jul 1998 |
| 460 | Rock Creek Oil Co. | Iowa Park, TX 76367 | Oil Operator | Mar 2008 |
| 461 | Rock Hill Operating | Burkburnett, TX 76354 | Oil & Gas Operator | Mar 2025 |
| 462 | Rockstar Production, LLC | Graham, TX 76450 | Oil Operator | Mar 2025 |
| 463 | Rocky Point Oil, Inc. | Wichita Falls, TX 76308 | Oil & Gas Operator | Mar 2025 |
| 464 | Rog Enterprises, Inc. | Lake Dallas, TX 75065 | Oil Operator | May 2014 |
| 465 | Rog Enterprises, LLC | Burkburnett, TX 76354 | Oil Operator | Mar 2025 |
| 466 | Roil Mineral & Land Co. | Dallas, TX 75379 | Oil & Gas Operator | Mar 2025 |
| 467 | Romac Oil Company, Inc. | Throckmorton, TX 76483 | Oil & Gas Operator | Mar 2025 |
| 468 | Ross, Dwight M. DRLG. Co., Inc. | Wichita Falls, TX 76301 | Oil & Gas Operator | Mar 2025 |
| 469 | Rover Operating Company, LLC | Wichita Falls, TX 76308 | Oil & Gas Operator | Mar 2025 |
| 470 | Royal Petroleum Co. | Iowa Park, TX 76367 | Oil & Gas Operator | Mar 2025 |
| 471 | RRG Operating, LLC | Odessa, TX 79760 | Oil & Gas Operator | Mar 2025 |
| 472 | Rucker, Gary | Archer City, TX 76351 | Oil & Gas Operator | Dec 2003 |
| 473 | Rush Creek Operating LLC | McKinney, TX 75070 | Oil & Gas Operator | Mar 2025 |
| 474 | Rusk Production Inc. | Iowa Park, TX 76367 | Oil & Gas Operator | Mar 2025 |
| 475 | Rutledge, Rome | Wichita Falls, TX 76301 | Oil & Gas Operator | Apr 1997 |
| 476 | Rutledge-Newsom | Graham, TX 76450 | Oil Operator | Mar 2025 |
| 477 | Rwa, LLC | Boyd, TX 76023 | Oil & Gas Operator | Mar 2025 |
| 478 | S & H Wells | Iowa Park, TX 76367 | Oil Operator | Mar 2025 |
| 479 | S & J Operating Company | Wichita Falls, TX 76301 | Oil & Gas Operator | Mar 2015 |
| 480 | S & M Drilling, LLC | Wichita Falls, TX 76308 | Oil Operator | Sep 2023 |
| 481 | S & R Oil Company | Electra, TX 76360 | Oil & Gas Operator | Apr 1993 |
| 482 | S & S Oil Company | Electra, TX 76360 | Oil & Gas Operator | Mar 2025 |
| 483 | S&G Oil LLC | Wichita Falls, TX 76309 | Oil & Gas Operator | Mar 2025 |
| 484 | S&S Heidrich | Iowa Park, TX 76367 | Oil & Gas Operator | Dec 2017 |
| 485 | S.B. Street Operating, Inc. | Graham, TX 76450 | Oil & Gas Operator | Mar 2025 |
| 486 | Saba Energy Of Texas Inc | Houston, TX 77042 | Oil & Gas Operator | Jul 2007 |
| 487 | Sabre Operating, Inc. | Wichita Falls, TX 76308 | Oil & Gas Operator | Mar 2025 |
| 488 | Sage Energy Company | San Antonio, TX 78215 | Oil & Gas Operator | Mar 2025 |
| 489 | Salvador Oil, LLC | Dallas, TX 75201 | Oil & Gas Operator | Mar 2025 |
| 490 | Sargent, Jo Ann | Holliday, TX 76366 | Oil & Gas Operator | Aug 2003 |
| 491 | Sauder Management Company | Wichita Falls, TX 76307 | Oil & Gas Operator | Mar 2025 |
| 492 | Schaefer, Gary L. | Holliday, TX 76366 | Oil & Gas Operator | Mar 2017 |
| 493 | Schalk, Thomas S. | Wichita Falls, TX 76301 | Oil & Gas Operator | Aug 1995 |
| 494 | Schenk Oil Co. | Scotland, TX 76379 | Oil Operator | Mar 2025 |
| 495 | Scribner, Jeff | Wichita Falls, TX 76302 | Oil & Gas Operator | Dec 2004 |
| 496 | Seale, Don R. | Electra, TX 76360 | Oil & Gas Operator | Mar 2025 |
| 497 | Seelye, William L. | Plano, TX 75024 | Oil & Gas Operator | Oct 2005 |
| 498 | Segler, Charles | Holliday, TX 76366 | Oil & Gas Operator | Mar 2008 |
| 499 | Seismotech Energy, Incorporated | Plano, TX 75075 | Oil & Gas Operator | Aug 2003 |
| 500 | Seneca Exploration, LLC | Wichita Falls, TX 76308 | Oil Operator | Mar 2025 |