| 601 | Texas Crude-Wainoco-Hilliard | | Oil & Gas Operator | Jul 1978 |
| 602 | Texas Eastern Skyline Oil | Houston, TX 77252 | Oil & Gas Operator | Jan 1987 |
| 603 | Texas Eastern Skyline Oil Co. | | Oil & Gas Operator | Jan 1987 |
| 604 | Texas Eastern Transm. Corp. | | Oil & Gas Operator | Dec 2002 |
| 605 | Texas Energen Inc. | Austin, TX 78731 | Oil & Gas Operator | Dec 2025 |
| 606 | Texas Energies I | | Oil & Gas Operator | Aug 1994 |
| 607 | Texas Energies Inc | Pratt, KS 67124 | Oil & Gas Operator | Aug 1998 |
| 608 | Texas Energy & Environmental | Houston, TX 77070 | Oil & Gas Operator | Nov 1998 |
| 609 | Texas Energy & Environmental Inc | Houston, TX 77269 | Oil & Gas Operator | Oct 1998 |
| 610 | Texas Energy Mutual LLC | Grapevine, TX 76051-8145 | Oil Operator | Jun 2018 |
| 611 | Texas Energy Operations, LC | Wichita Falls, TX 76301 | Oil & Gas Operator | Dec 2025 |
| 612 | Texas Energy Reserves, Inc | New Braunfels, TX 78130 | Oil & Gas Operator | Jun 1996 |
| 613 | Texas Energy Sources, Inc. | Midland, TX 79708 | Oil & Gas Operator | Mar 2008 |
| 614 | Texas Energy Trust Company | Midland, TX 79701 | Oil & Gas Operator | Jun 2016 |
| 615 | Texas Exploration & Prod. Co. | Gainesville, TX 76240 | Oil & Gas Operator | Apr 1996 |
| 616 | Texas Fuel Company | Galveston, TX 77550 | Oil & Gas Operator | Dec 2025 |
| 617 | Texas Gas Exploration Corp. | | Oil & Gas Operator | Nov 1986 |
| 618 | Texas Gas Resources, Inc. | Houston, TX 77292 | Oil & Gas Operator | Jul 2009 |
| 619 | Texas Gas Transmission Corp. | | Oil Operator | Aug 2003 |
| 620 | Texas Gas Transmission, LLC | Owensboro, KY 42301 | Oil & Gas Operator | Dec 2024 |
| 621 | Texas General Petroleum Corp | | Oil & Gas Operator | Aug 1984 |
| 622 | Texas Gulf Gas Corporation | Fayetteville, TX 78940 | Oil & Gas Operator | Jun 2005 |
| 623 | Texas Hydrogen Energy Corp. | Midland, TX 79702 | Oil & Gas Operator | May 1999 |
| 624 | Texas Ind. Exploration, Inc. | | Oil & Gas Operator | Oct 2001 |
| 625 | Texas Independent Explor LTD. | Houston, TX 77024 | Oil & Gas Operator | Dec 2025 |
| 626 | Texas Independent Explor., Inc. | Houston, TX 77002 | Oil & Gas Operator | Oct 2002 |
| 627 | Texas Independent Exploration LP | Houston, TX 77024 | Oil & Gas Operator | Mar 2017 |
| 628 | Texas Independent Oil Co., LLC | Argyle, TX 76226 | Oil & Gas Operator | Dec 2025 |
| 629 | Texas International Oper., LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Dec 2013 |
| 630 | Texas International Resource LLC | Allen, TX 75013 | Oil Operator | Dec 2025 |
| 631 | Texas Investments | San Angelo, TX 76904 | Oil & Gas Operator | Mar 2008 |
| 632 | Texas Keystone Inc | Oakmont, PA 15139-2072 | Oil & Gas Operator | Nov 2017 |
| 633 | Texas Land & Petro Co., LLC | Carrollton, TX 75010 | Oil & Gas Operator | Dec 2025 |
| 634 | Texas Land & Trading Co, Inc. | Austin, TX 78734 | Oil & Gas Operator | Mar 2008 |
| 635 | Texas Lone Star Petroleum Corp. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Dec 2013 |
| 636 | Texas M.O.R., Inc. | Corsicana, TX 75109 | Oil Operator | Sep 2013 |
| 637 | Texas Meridian Operating Co. Inc | Houston, TX 77079 | Oil & Gas Operator | Oct 1993 |
| 638 | Texas Meridian Res. Expl., Inc. | Houston, TX 77079 | Oil & Gas Operator | Jun 1998 |
| 639 | Texas Mineral Group | Midland, TX 79705 | Oil & Gas Operator | Aug 2013 |
| 640 | Texas Moran Exploration Company | Houston, TX 77098 | Oil & Gas Operator | Jun 2023 |
| 641 | Texas Offshore Operations, LLC | Farmers BRNCH, TX 75234 | Oil & Gas Operator | Dec 2025 |
| 642 | Texas Oil & Gas | Denver, CO 80264 | Oil & Gas Operator | Oct 1981 |
| 643 | Texas Oil & Gas Corporation | Dallas, TX 75201 | Oil & Gas Operator | Feb 2001 |
| 644 | Texas Oil And Gas Operating, LLC | Friendswood, TX 77546 | Oil & Gas Operator | Dec 2025 |
| 645 | Texas Oil Company, The | Houston, TX 77018 | Oil & Gas Operator | Aug 2006 |
| 646 | Texas Oil Resources Oper, LLC | Houston, TX 77024 | Oil Operator | Dec 2025 |
| 647 | Texas Onshore Energy, Inc. | Austin, TX 78704 | Oil & Gas Operator | Dec 2025 |
| 648 | Texas Operating & Consult., LLC | Abilene, TX 79608 | Oil & Gas Operator | Feb 2018 |
| 649 | Texas Operating Partners LLC | Tomball, TX 77377 | Oil & Gas Operator | Dec 2025 |
| 650 | Texas Pacific Oil Co. | | Oil & Gas Operator | Dec 1980 |
| 651 | Texas Petroleum Investment Company | Houston, TX 77057 | Oil & Gas Operator | Dec 2025 |
| 652 | Texas Pharchem Inc. | Abilene, TX 79601 | Oil & Gas Operator | Apr 2019 |
| 653 | Texas Presco, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Dec 2025 |
| 654 | Texas Rayco Inc. | Palmetto, FL 34221 | Oil & Gas Operator | Dec 2025 |
| 655 | Texas Reexploration Operating LC | Fredericksbrg, TX 78624 | Oil & Gas Operator | Dec 2025 |
| 656 | Texas Refining, Inc. | Houston, TX 77057 | Oil & Gas Operator | Aug 2003 |
| 657 | Texas Royalty Corp. | Austin, TX 78746 | Oil & Gas Operator | Dec 2025 |
| 658 | Texas Sands Resources, LLC | Abilene, TX 79603 | Oil Operator | Dec 2025 |
| 659 | Texas Secondary Oil Corporation | Devine, TX 78016 | Oil & Gas Operator | Dec 2025 |
| 660 | Texas Shallow Oil & Gas, LLC | Graham, TX 76450 | Oil & Gas Operator | Dec 2025 |
| 661 | Texas South Operating Co, Inc. | Houston, TX 77027 | Oil Operator | Dec 2025 |
| 662 | Texas Southern Petroleum Corp. | Corpus Chrsti, TX 78410 | Oil & Gas Operator | Dec 2025 |
| 663 | Texas Standard Oil Operating Co. | Midland, TX 79705 | Oil & Gas Operator | Oct 2019 |
| 664 | Texas State Oil Co. | Irving, TX 75062 | Oil & Gas Operator | Mar 2017 |
| 665 | Texas Sunset Energy And Ent Inc | Victoria, TX 77904 | Oil Operator | Aug 2003 |
| 666 | Texas T Oil Co. | | Oil & Gas Operator | Apr 1990 |
| 667 | Texas Tea Of Colorado LLC Dba Texas Tea LLC | | Oil & Gas Operator | Jun 2021 |
| 668 | Texas Tea Oil Company | Jacksboro, TX 76458 | Oil & Gas Operator | Feb 2011 |
| 669 | Texas Trade International Inc. | Andrews, TX 79714 | Oil Operator | Dec 2025 |
| 670 | Texas United Geoproduction, Inc. | Abilene, TX 79606 | Oil & Gas Operator | Dec 2025 |
| 671 | Texas United Petroleum Inc | Dallas, TX 75243 | Oil & Gas Operator | Jun 2003 |
| 672 | Texas Utilities Fuel Co. | Dallas, TX 75201 | Oil & Gas Operator | Mar 2018 |
| 673 | Texas Utilities Mining Co. | Dallas, TX 75201 | Oil & Gas Operator | May 1995 |
| 674 | Texas Valley Oil & Gas, LLC | Hidalgo, TX 78557 | Oil Operator | Dec 2025 |
| 675 | Texas Vanguard Oil Company | Austin, TX 78720 | Oil & Gas Operator | Jan 2014 |
| 676 | Texas Western Energy Corporation | Portland, TX 78374 | Oil & Gas Operator | Nov 2002 |
| 677 | Texas Western Oil Company | Sioux Falls, SD 57109 | Oil & Gas Operator | Sep 2013 |
| 678 | Texas, Les & Co. | Brenham, TX 77833 | Oil & Gas Operator | Dec 2025 |
| 679 | Texas, Les C., LTD. | Houston, TX 77095 | Oil & Gas Operator | Dec 2006 |
| 680 | Texas-Australia Power Inc. | Wichita Falls, TX 76302 | Oil & Gas Operator | Dec 2011 |
| 681 | Texas-Ohio Producing Company | Spring, TX 77383 | Oil & Gas Operator | Jul 1995 |
| 682 | Texas/Arkansas P | | Oil & Gas Operator | Sep 1990 |
| 683 | Texasgulf Inc. | Newgulf, TX 77462 | Oil & Gas Operator | Jul 1994 |
| 684 | Texcal Energy (GP) LLC | Denver, CO 80202 | Oil & Gas Operator | Mar 2016 |
| 685 | Texcal Oil Co | Cuero, TX 77954 | Oil & Gas Operator | Feb 2006 |
| 686 | Texcal Oil Inc. | Vidor, TX 77662 | Oil & Gas Operator | Jun 1994 |
| 687 | Texcal Resources, Inc. | Plano, TX 75094 | Oil & Gas Operator | Apr 1994 |
| 688 | Texcel Exploration, Inc. | Colorado SPGS, CO 80960 | Oil & Gas Operator | Dec 2025 |
| 689 | Texco Operating Co. | San Antonio, TX 78209 | Gas Operator | Aug 2003 |
| 690 | Texcrude Services LLC | Iowa Park, TX 76367 | Oil Operator | Dec 2025 |
| 691 | Texdon Operating | Breckenridge, TX 76424 | Oil & Gas Operator | Jun 2005 |
| 692 | Texeast Operating Co., Inc. | Farmers BRNCH, TX 75234 | Oil Operator | Dec 2025 |
| 693 | Texegy Operating Company LLC | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Dec 2024 |
| 694 | Texex Petroleum Corporation | | Oil & Gas Operator | Dec 2024 |
| 695 | Texian Energy Corporation | Amarillo, TX 79120 | Oil & Gas Operator | Apr 1997 |
| 696 | Texian Operating Company, LLC | Irving, TX 75063 | Oil & Gas Operator | Dec 2025 |
| 697 | Texical, Inc. | Katy, TX 77491 | Oil & Gas Operator | Dec 2025 |
| 698 | Texinia Corp | Dallas, TX 75201 | Oil & Gas Operator | Jun 2015 |
| 699 | Texinia Limited Partnership | Dallas, TX 75201 | Gas Operator | Jan 2017 |
| 700 | Texinia Oil & Gas Inc | Dallas, TX 75214 | Oil & Gas Operator | Aug 2025 |