| 30501 | Twins Oil Co. | Monahans, TX 79756 | Oil & Gas Operator | Dec 2025 |
| 30502 | Twisted Oak Operating LLC | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 30503 | Twisted Resources Inc | Blanchard, OK 73010-8463 | Oil & Gas Operator | Oct 2025 |
| 30504 | TWM Production Co., A General Partnership | Chanute, KS 66720 | Oil Operator | May 2025 |
| 30505 | Two Bay Petroleum | | Oil & Gas Operator | Dec 2010 |
| 30506 | Two Bayous, Inc. | | Oil & Gas Operator | Dec 2024 |
| 30507 | Two Bit Operating Company LLC | Fort Worth, TX 76110 | Oil & Gas Operator | Dec 2025 |
| 30508 | Two Black Bears Oil, Inc. | Midland, TX 79710 | Oil & Gas Operator | Sep 2003 |
| 30509 | Two Gems Company | McAlester, OK 74502-1996 | Oil & Gas Operator | Sep 2025 |
| 30510 | Two Oaks Operating Company, LLC. | Flower Mound, TX 75028 | Oil & Gas Operator | Mar 2008 |
| 30511 | Two P Partners, LLC | Houston, TX 77056 | Oil & Gas Operator | Dec 2025 |
| 30512 | Two Pines | Drumright, OK 74030-5502 | Oil & Gas Operator | Feb 2012 |
| 30513 | Twojo, Inc. | Longview, TX 75601 | Oil & Gas Operator | Nov 1996 |
| 30514 | TX Heat Of The Permian Basin Inc | Odessa, TX 79768 | Oil & Gas Operator | Dec 2021 |
| 30515 | TX Lone Star Operating Co, LLC | Sulphur SPGS, TX 75483 | Oil & Gas Operator | Dec 2025 |
| 30516 | TX Petroleum Company | Corpus Chrsti, TX 78412 | Oil & Gas Operator | Apr 1996 |
| 30517 | Txco Resources Inc. | San Antonio, TX 78280 | Oil & Gas Operator | Dec 2025 |
| 30518 | Txla Energy, Inc. | Houston, TX 77018 | Oil & Gas Operator | Dec 2025 |
| 30519 | Txo Prod Corp.-Arkla Expl. Co. | | Oil & Gas Operator | Dec 1990 |
| 30520 | Txo Production Corp. | Ganado, TX 77962 | Oil & Gas Operator | Aug 2022 |
| 30521 | Txo Production Corp/Amh O&G Co | | Oil & Gas Operator | Dec 1990 |
| 30522 | Txok Energy Resources Company | Tulsa, OK 74172-0140 | Oil & Gas Operator | Feb 2017 |
| 30523 | Txok Texas Energy Resources,L.P. | Dallas, TX 75251 | Oil & Gas Operator | Apr 2008 |
| 30524 | Txon Partners, LLC | Houston, TX 77057 | Oil & Gas Operator | Jun 2017 |
| 30525 | TXP Operating Co. | | Oil & Gas Operator | Jul 1992 |
| 30526 | TXP, Incorporated | San Angelo, TX 76906 | Oil & Gas Operator | Dec 2025 |
| 30527 | Txu Fuel Company | Dallas, TX 75201 | Oil & Gas Operator | May 2004 |
| 30528 | Txu Gas Company | Dallas, TX 75201 | Oil & Gas Operator | Sep 2004 |
| 30529 | Txu Lone Star Pipeline | Dallas, TX 75201 | Oil & Gas Operator | Oct 2003 |
| 30530 | TXX Operating LLC | Shreveport, LA 71133 | Oil & Gas Operator | Dec 2025 |
| 30531 | Ty-Tex Exploration, Inc. | Tyler, TX 75711 | Oil Operator | Dec 2000 |
| 30532 | Tyco Incorporate | | Oil & Gas Operator | Oct 1995 |
| 30533 | Tyco Oil Co. | | Oil Operator | Jan 2025 |
| 30534 | Tyco Operating Co. | Archer City, TX 76351 | Oil & Gas Operator | Dec 2025 |
| 30535 | Tyco, Inc. | Independence, KS 67301 | Oil & Gas Operator | Jan 1998 |
| 30536 | Tyco, Inc. (Colorado Corporation) | Independence, KS 67301 | Gas Operator | Jun 1998 |
| 30537 | Tygr Operating Company, LLC | | Oil & Gas Operator | Nov 2024 |
| 30538 | Tyl Oil | Canon City, CO 81212 | Gas Operator | May 1994 |
| 30539 | Tyler Enterprises Inc | Bristow, OK 74010-3192 | Oil & Gas Operator | Feb 2004 |
| 30540 | Tyler Oil & Gas Inc. | Tyler, TX 75702 | Oil & Gas Operator | Sep 2004 |
| 30541 | Tyler Oil Company | Billings, MT 59104-3203 | Oil & Gas Operator | Nov 2019 |
| 30542 | Tyler Production, LLC | | Oil & Gas Operator | Jul 2013 |
| 30543 | Tyler Rockies Exploration LTD | Tyler, TX 75710-0119 | Oil & Gas Operator | Oct 2025 |
| 30544 | Tyler, Scott A | | Oil & Gas Operator | Sep 2025 |
| 30545 | Tyler, Steven Lee | | Oil Operator | May 2014 |
| 30546 | Tyluka Operations, LLC | Hays, KS 67601 | Oil Operator | May 2025 |
| 30547 | Tyner Texas Operating Company | Dallas, TX 75248 | Oil & Gas Operator | Dec 2025 |
| 30548 | Tyrex Oil Company | Casper, WY 82602 | Oil & Gas Operator | May 1997 |
| 30549 | Tyro Oil Develop | | Oil Operator | Jul 1991 |
| 30550 | Tyrok | | Oil & Gas Operator | Nov 2010 |
| 30551 | Tysco Oil And Gas Corp. | | Oil & Gas Operator | Dec 2024 |
| 30552 | Tyson Gary | Hobart, OK 73651-6413 | Oil & Gas Operator | Mar 2018 |
| 30553 | Tyson Oil Co. | | Oil Operator | Jan 2025 |
| 30554 | Tyson Olan | Hobart, OK 73651-6413 | Oil & Gas Operator | Apr 2015 |
| 30555 | Tytan Operating Company LLC | Edmond, OK 73083-3794 | Oil & Gas Operator | May 2016 |
| 30556 | U Bee Tea Production LLC | Culbertson, MT 59218 | Oil & Gas Operator | Oct 2025 |
| 30557 | U R C C | | Oil & Gas Operator | Jun 1991 |
| 30558 | U S Drilling Company Inc | Holdenville, OK 74848-0913 | Oil & Gas Operator | Mar 2017 |
| 30559 | U S Energy Corp. Of Amer. Inc. | Cisco, TX 76437 | Oil & Gas Operator | Dec 2025 |
| 30560 | U S Exploraton Liq Trust | | Oil & Gas Operator | Oct 1994 |
| 30561 | U S Liquids Of La., L.P. | | Oil Operator | Apr 2014 |
| 30562 | U V Industries | | Oil & Gas Operator | Jan 1993 |
| 30563 | U-N-I Exploratio | | Oil & Gas Operator | Dec 1990 |
| 30564 | U-N-I Exploration & Development, Inc. | Yates Center, KS 66783 | Oil & Gas Operator | Jan 2003 |
| 30565 | U. D. Man, Inc. | San Antonio, TX 78212 | Oil & Gas Operator | Dec 2025 |
| 30566 | U. O. C., Inc. | | Oil Operator | Jun 2019 |
| 30567 | U. S. Energy Development Corporation | Fort Worth, TX 76164 | Oil & Gas Operator | Dec 2025 |
| 30568 | U. S. Operating, Inc. | Dallas, TX 75252 | Oil & Gas Operator | Jul 2025 |
| 30569 | U.S. Capital Corp Of Am, Inc. | | Oil & Gas Operator | Aug 1998 |
| 30570 | U.S. Enercorp, LLC | San Antonio, TX 78217 | Oil & Gas Operator | Jul 2004 |
| 30571 | U.S. Enercorp, LTD. | San Antonio, TX 78209 | Oil & Gas Operator | Sep 2019 |
| 30572 | U.S. Exploration Company | Houston, TX 77002 | Oil & Gas Operator | Aug 2003 |
| 30573 | U.S. Oil Reclaimers, LLC | | Oil Operator | Jun 2023 |
| 30574 | U.S. Sovereign Oil And Gas, Inc. | Dallas, TX 75355 | Oil & Gas Operator | Dec 2025 |
| 30575 | U.S. Steel Mining Co., Inc. | | Gas Operator | Jan 2000 |
| 30576 | U.S. Steel Mining Co., LLC | | Gas Operator | Oct 2002 |
| 30577 | U.S.A. Plugging Company | Pearsall, TX 78061 | Oil & Gas Operator | Dec 2025 |
| 30578 | U1 Ranch Oil | Houston, TX 77269 | Oil & Gas Operator | Dec 2025 |
| 30579 | Uae Investco 1 (Estill), LLC | Ravenna, KY 40472 | Oil Operator | Dec 2022 |
| 30580 | Uae Investco 2 (Lee), LLC | Ravenna, KY 40472 | Oil Operator | Dec 2021 |
| 30581 | Ubetco, Inc. | Rockdale, TX 76567 | Oil & Gas Operator | Dec 2025 |
| 30582 | Uebelhor, Theodore | | Oil Operator | Dec 2023 |
| 30583 | Uehlin LLC | Oberlin, KS 67749 | Oil Operator | Dec 2024 |
| 30584 | Uhc New Mexico Corporation | Midland, TX 79702 | Oil & Gas Operator | Feb 2007 |
| 30585 | Uhc Petroleum Corporation | Rocksprings, TX 78880 | Oil & Gas Operator | Dec 2025 |
| 30586 | Uhl Oil Co., Inc. | Bradford, PA 16701 | Oil & Gas Operator | Dec 2024 |
| 30587 | Uhls, Jimmie J. | Sedan, KS 67361 | Oil Operator | Sep 2019 |
| 30588 | Uinta Oil & Gas | Roosevelt, UT 84066 | Oil & Gas Operator | Nov 1997 |
| 30589 | Uinta Wax Operating, LLC | Fort Worth, TX 76107 | Oil & Gas Operator | Oct 2025 |
| 30590 | Uintah Investors LLC | Vernal, UT 84078 | Oil & Gas Operator | Oct 2025 |
| 30591 | Ulatex Oil & Gas Inc. | Nocona, TX 76255 | Oil & Gas Operator | Dec 1998 |
| 30592 | Ulrich, William J., Jr. & Connie K. | Elma, NY 14059 | Gas Operator | Dec 2024 |
| 30593 | Ultra Oil & Gas, Inc. | Centerton, AR 72719 | Oil & Gas Operator | Dec 2025 |
| 30594 | Ultra Petroleum (U.S.A.), Inc. | Granbury, TX 76048 | Oil & Gas Operator | Sep 2003 |
| 30595 | Ultra Production Company, LLC | Cedar Bluff, VA 24609 | Gas Operator | Oct 2014 |
| 30596 | Ultra Resources Inc | Houston, TX 77060 | Oil & Gas Operator | Sep 2018 |
| 30597 | Ultramar Oil & Gas LTD | Houston, TX 77060 | Oil & Gas Operator | Jul 1995 |
| 30598 | Ultramar Production Company | | Oil & Gas Operator | Dec 1991 |
| 30599 | Ulysses, City Of | Ulysses, KS 67880 | Gas Operator | Jun 2025 |
| 30600 | Umad LLC | | Oil & Gas Operator | Feb 2010 |