| 12001 | Walsh Petroleum, Inc. | Midland, TX 79702 | Oil & Gas Operator | Dec 2022 |
| 12002 | Walsh Resources, Inc. | Tyler, TX 75713 | Oil & Gas Operator | Dec 2025 |
| 12003 | Walsh, F H Jr. Operating Co. Inc | Fort Worth, TX 76102 | Oil & Gas Operator | Oct 2019 |
| 12004 | Walsh, F. Howard, Jr. | Fort Worth, TX 76102 | Oil & Gas Operator | Apr 1994 |
| 12005 | Walter Exploration Company | Dallas, TX 75206 | Oil & Gas Operator | Dec 2025 |
| 12006 | Walter Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | May 2009 |
| 12007 | Walter H. Husfeld Oil Co LLC | Bowie, TX 76230 | Oil & Gas Operator | Dec 2025 |
| 12008 | Walter Oil & Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Dec 2025 |
| 12009 | Walterscheid, A. D. | Muenster, TX 76252 | Oil & Gas Operator | Dec 2014 |
| 12010 | Walterscheid, R. F. | Muenster, TX 76252 | Oil & Gas Operator | Oct 1993 |
| 12011 | Walton Producing Company | Breckenridge, TX 76424 | Oil & Gas Operator | Jul 2005 |
| 12012 | Walton Producing Inc. | Breckenridge, TX 76424 | Oil & Gas Operator | Dec 2025 |
| 12013 | Walton Properties LTD. | Midland, TX 79702 | Oil & Gas Operator | Feb 2004 |
| 12014 | Walton, James A. | Midland, TX 79702 | Oil & Gas Operator | Oct 1994 |
| 12015 | Walton, W. W. | Breckenridge, TX 76424 | Oil & Gas Operator | Sep 1994 |
| 12016 | Wam Energy Corporation | Dallas, TX 75206 | Oil & Gas Operator | Dec 2016 |
| 12017 | Wandoo Energy, LLC | The Woodlands, TX 77382 | Oil & Gas Operator | Dec 2025 |
| 12018 | Wapiti Energy, LLC | Houston, TX 77024 | Oil & Gas Operator | Jul 2006 |
| 12019 | Wapiti Operating, LLC | Houston, TX 77043 | Oil & Gas Operator | Dec 2025 |
| 12020 | Warbonnet Exploration Company | Houston, TX 77056 | Oil & Gas Operator | Apr 2016 |
| 12021 | Ward Oil Co. | Kilgore, TX 75663 | Oil & Gas Operator | Dec 2025 |
| 12022 | Ward Trust | Spring, TX 77383 | Oil & Gas Operator | May 2013 |
| 12023 | Ward, Charles Oil Company | Olney, TX 76374 | Oil Operator | Dec 2025 |
| 12024 | Ward, E. B. | Alice, TX 78333 | Oil & Gas Operator | Jun 2001 |
| 12025 | Ward, L. S. | Graham, TX 76450 | Oil & Gas Operator | Jun 2001 |
| 12026 | Ward, Ted G. Jr. | Monahans, TX 79756 | Oil & Gas Operator | Nov 2000 |
| 12027 | Warner Oil Co., Inc. | Canyon, TX 79015 | Oil & Gas Operator | May 2013 |
| 12028 | Warner Sisters, LLC | Thompsons Sta, TN 37179 | Oil Operator | Dec 2025 |
| 12029 | Warner, Mark T. Oil Co | Pampa, TX 79065 | Oil & Gas Operator | Jul 2021 |
| 12030 | Warner-Pawel | Alice, TX 78333 | Oil & Gas Operator | Dec 2025 |
| 12031 | Warnock Operating Company, LLC | Graham, TX 76450 | Oil & Gas Operator | Jul 2013 |
| 12032 | Warren American Oil Co | Tulsa, OK 74147 | Oil & Gas Operator | Oct 2025 |
| 12033 | Warren American Oil Company LLC | Tulsa, OK 74147 | Oil & Gas Operator | Dec 2025 |
| 12034 | Warren Producers Inc | Bowling Green, KY 42102 | Oil & Gas Operator | Dec 2017 |
| 12035 | Warren Production Services | Caldwell, TX 77836 | Oil & Gas Operator | Dec 2025 |
| 12036 | Warren, Earl T. | San Angelo, TX 76906 | Oil & Gas Operator | Dec 2025 |
| 12037 | Warren, Joe H. | Dallas, TX 75206 | Oil & Gas Operator | Oct 2001 |
| 12038 | Warrior Exploration LLC | Sapulpa, OK 74067-1912 | Oil & Gas Operator | Aug 2025 |
| 12039 | Warrior Resources Inc. | Mexia, TX 76667 | Oil & Gas Operator | Dec 2025 |
| 12040 | Warwick Associates LC | Oklahoma City, OK 73112 | Oil & Gas Operator | Sep 2025 |
| 12041 | Warwick Oil & Gas, Inc. | Houston, TX 77098 | Oil & Gas Operator | Feb 1993 |
| 12042 | Warwick-Artemis, LLC | Nichols Hill, OK 73116 | Oil & Gas Operator | Dec 2025 |
| 12043 | Wash, Robert C. | Forsan, TX 79733 | Oil & Gas Operator | Nov 2000 |
| 12044 | Wash, Robert C. Inc. | Forsan, TX 79733 | Oil & Gas Operator | Dec 2025 |
| 12045 | Washita Oil And Gas, L.L.C. | Tulsa, OK 74136 | Oil & Gas Operator | Mar 2015 |
| 12046 | Washita Production Company | Tulsa, OK 74136 | Oil & Gas Operator | May 2006 |
| 12047 | Watco Energy | Jacksboro, TX 76458 | Oil & Gas Operator | Dec 2025 |
| 12048 | Watco Energy, Inc. | Tyler, TX 75713 | Oil & Gas Operator | Apr 1996 |
| 12049 | Water Works Engineering, Inc. | Rockdale, TX 76567 | Oil & Gas Operator | Jan 1998 |
| 12050 | Waterbridge Texas Operating LLC | Houston, TX 77056 | Oil & Gas Operator | Dec 2025 |
| 12051 | Waters Eng. & Operating, Inc. | Corpus Chrsti, TX 78471 | Oil & Gas Operator | Sep 2013 |
| 12052 | Waters Petroleum | Albany, TX 76430 | Oil & Gas Operator | Aug 2016 |
| 12053 | Watkins Production Company | Dallas, TX 75229 | Oil & Gas Operator | Feb 2008 |
| 12054 | Watkins, J. B. | Borger, TX 79007 | Oil & Gas Operator | May 2009 |
| 12055 | Watson Energy Investments, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2025 |
| 12056 | Watson Oil & Gas Co. | Gorman, TX 76454 | Oil & Gas Operator | Jan 2002 |
| 12057 | Watson Oil & Gas, Inc. | Spicewood, TX 78669 | Oil & Gas Operator | Dec 2025 |
| 12058 | Watson Operating Company | Pampa, TX 79066 | Oil & Gas Operator | Dec 2003 |
| 12059 | Watson Packer Employee Fund | Monahans, TX 79756 | Oil & Gas Operator | Dec 2025 |
| 12060 | Watson, B. G. Oil Field Salv Inc | Coleman, TX 76834 | Oil & Gas Operator | Mar 2000 |
| 12061 | Watt Energy, LLC | Port Barre, LA 70577 | Oil & Gas Operator | Dec 2025 |
| 12062 | Watusi Energy LLC | Midland, TX 79710 | Oil & Gas Operator | Dec 2025 |
| 12063 | Way, Ralph L., Inc. | Midland, TX 79701 | Oil & Gas Operator | Dec 2025 |
| 12064 | Wayhan Oil Company | Houston, TX 77070 | Oil & Gas Operator | Dec 2025 |
| 12065 | Wayland Drilling & Explr., Inc. | Grapevine, TX 76099 | Oil & Gas Operator | Apr 2006 |
| 12066 | Waylander LLC | Plano, TX 75025 | Oil & Gas Operator | Dec 2025 |
| 12067 | Waymar Oil & Gas Company | Texarkana, TX 75503 | Oil & Gas Operator | Jan 2007 |
| 12068 | Wayne E. Glenn Associates, Inc. | Dickinson, TX 77539 | Oil & Gas Operator | Jan 2016 |
| 12069 | WB Mullin Operating LLC | Graham, TX 76450 | Oil & Gas Operator | Dec 2025 |
| 12070 | WBH Energy Partners LLC | Austin, TX 78703 | Oil & Gas Operator | Dec 2025 |
| 12071 | WBR, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Sep 1995 |
| 12072 | WCS Oil & Gas Corporation | Dallas, TX 75209 | Oil & Gas Operator | Aug 2021 |
| 12073 | WCT Leasing Co. | Austin, TX 78734 | Oil & Gas Operator | Apr 2019 |
| 12074 | WCWB Energy, LLC | Midland, TX 79701 | Oil Operator | Sep 2015 |
| 12075 | Weakland Investments, Inc. | Denver, CO 80215 | Oil & Gas Operator | Dec 2025 |
| 12076 | Weatherly Oil & Gas, LLC | Dallas, TX 75206 | Oil & Gas Operator | Dec 2025 |
| 12077 | Weathers Exploration, Inc. | Tyler, TX 75702 | Oil & Gas Operator | Dec 2025 |
| 12078 | Weatherston, George D. | San Antonio, TX 78217 | Oil & Gas Operator | Oct 2001 |
| 12079 | Weaver & Sharp | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Mar 1997 |
| 12080 | Weaver Global Operating, LLC | Colleyville, TX 76034 | Oil Operator | Dec 2025 |
| 12081 | Weber Energy Corporation | Dallas, TX 75219 | Oil & Gas Operator | Feb 2017 |
| 12082 | Weeks Exploration Company | Houston, TX 77063 | Oil & Gas Operator | Aug 1995 |
| 12083 | Wefco, Inc. | Pampa, TX 79065 | Oil & Gas Operator | May 1993 |
| 12084 | Wehunt Oil Company, Inc. | Dallas, TX 75376 | Oil & Gas Operator | Nov 2002 |
| 12085 | Weibye, Carolyn S. | Houston, TX 77098 | Oil & Gas Operator | Dec 2025 |
| 12086 | Weinkauf Petroleum, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Sep 2025 |
| 12087 | Weinstrom Petroleum | Devine, TX 78016 | Oil & Gas Operator | Dec 2025 |
| 12088 | Weiser-Brown Oil Co | Magnolia, AR 71754 | Oil Operator | Jan 2025 |
| 12089 | Weiser-Brown Operating Company | Magnolia, AR 71754 | Oil & Gas Operator | Dec 2025 |
| 12090 | Weiss Oil Co. | Streator, IL 61364 | Oil & Gas Operator | Dec 1997 |
| 12091 | Wejco, Inc. | Rising Star, TX 76471 | Oil & Gas Operator | Dec 2025 |
| 12092 | Welcome Well Serv. & Boykin Bros | Abilene, TX 79604 | Oil & Gas Operator | Apr 1995 |
| 12093 | Welder Exploration & Prod., Inc. | San Antonio, TX 78212 | Oil & Gas Operator | Dec 2022 |
| 12094 | Welder Operating, Inc. | San Antonio, TX 78205 | Oil & Gas Operator | Mar 2001 |
| 12095 | Welder-Heyer Energy, Inc. | San Antonio, TX 78205 | Oil & Gas Operator | Feb 2001 |
| 12096 | Welderxp LTD. | San Antonio, TX 78212 | Oil & Gas Operator | Dec 2025 |
| 12097 | Weldon Corporation | Houston, TX 77056 | Oil Operator | Feb 2020 |
| 12098 | Welhausen Operating Co., Inc. | Beeville, TX 78104 | Oil & Gas Operator | Aug 2003 |
| 12099 | Welhausen Operating Company, LP | Beeville, TX 78104 | Oil & Gas Operator | Nov 2016 |
| 12100 | Well Recycling Company | Olney, TX 76374 | Oil Operator | Aug 2005 |