| 1 | Adams Resources Expl. Corp. | Houston, TX 77001 | Oil & Gas Operator | Apr 2020 |
| 2 | Ads | Caldwell, TX 77836 | Oil & Gas Operator | Dec 2010 |
| 3 | Ads Oil & Gas, Inc. | Caldwell, TX 77836 | Oil & Gas Operator | May 2025 |
| 4 | Alcorn Prod Co. | Victoria, TX 77902 | Oil & Gas Operator | Mar 1997 |
| 5 | Alexander Energy Corporation | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 6 | Allegiant Resources, LLC | Lafayette, LA 70503 | Oil & Gas Operator | May 2025 |
| 7 | Amcon Resources, Inc. | Oklahoma City, OK 73101 | Gas Operator | Jun 2016 |
| 8 | Amoco Production Co. | Houston, TX 77253 | Oil & Gas Operator | Jun 2015 |
| 9 | Anadarko Austin Chalk Company | Houston, TX 77251 | Oil & Gas Operator | Feb 2006 |
| 10 | Anadarko E&P Company LP | Houston, TX 77251 | Oil & Gas Operator | Aug 2014 |
| 11 | Anadarko Petroleum Corporation | Houston, TX 77251 | Oil & Gas Operator | Mar 2025 |
| 12 | Anatexas Offshore, Inc. | Houston, TX 77024 | Oil & Gas Operator | May 2025 |
| 13 | Anchor Operating Co. | Houston, TX 77055 | Oil & Gas Operator | May 2025 |
| 14 | Aop Operating Corporation | Dallas, TX 75313 | Oil & Gas Operator | Aug 2003 |
| 15 | Apache Corporation | Houston, TX 77042 | Oil & Gas Operator | May 2025 |
| 16 | Arledge, Terry | Rockdale, TX 76567 | Oil & Gas Operator | Sep 2019 |
| 17 | Armor Energy LLC | Tulsa, OK 74146 | Oil & Gas Operator | Jun 2022 |
| 18 | Arrow Exploration Company | Plano, TX 75075 | Oil & Gas Operator | Dec 2004 |
| 19 | Atasca Resources Inc | Houston, TX 77219 | Oil & Gas Operator | May 2025 |
| 20 | Atkinson Energy Corporation | Giddings, TX 78942 | Oil & Gas Operator | Jan 2010 |
| 21 | Atlas Operating LLC | Houston, TX 77056 | Oil & Gas Operator | May 2025 |
| 22 | Austin Energy Operations, Inc. | Corpus Chrsti, TX 78410 | Oil & Gas Operator | May 2025 |
| 23 | Austin Minerals Inc. | Austin, TX 78720 | Oil & Gas Operator | May 2025 |
| 24 | B & B Drilling Co. | Milano, TX 76556 | Oil & Gas Operator | Jul 2015 |
| 25 | B & T Operating Co. | Dawson, TX 76639 | Oil & Gas Operator | May 2025 |
| 26 | B M Energy, Inc. | Hennessey, OK 73742 | Oil & Gas Operator | Jan 2022 |
| 27 | B-T Oil Field Supply, Inc. | Caldwell, TX 77836 | Oil & Gas Operator | Jul 2002 |
| 28 | Baird Oil Company Inc | Lewisville, TX 75067 | Oil & Gas Operator | May 2025 |
| 29 | Bar-Mac Investments Inc. | Brenham, TX 77834 | Oil & Gas Operator | Jun 2017 |
| 30 | Bass Petroleum | Austin, TX 78720 | Oil & Gas Operator | Aug 2004 |
| 31 | Bass Petroleum Inc | Austin, TX 78716 | Oil & Gas Operator | May 2025 |
| 32 | Bay Rock Operating Company | San Antonio, TX 78212 | Oil & Gas Operator | May 2025 |
| 33 | BC Operating, Inc. | Midland, TX 79710 | Oil & Gas Operator | May 2025 |
| 34 | Bellwether Exploration Company | Houston, TX 77010 | Oil & Gas Operator | May 2001 |
| 35 | Bet-Ro, Inc. | Rockdale, TX 76567 | Oil & Gas Operator | May 2025 |
| 36 | Black Dome Energy Corporation | Golden, CO 80401 | Oil & Gas Operator | Dec 2019 |
| 37 | Black Sable Energy, LLC | San Antonio, TX 78209 | Oil Operator | Jan 2018 |
| 38 | Black Stone Energy Company | Houston, TX 77002 | Oil & Gas Operator | Mar 2004 |
| 39 | Blessing Energy, Inc. | Giddings, TX 78942 | Oil & Gas Operator | May 2025 |
| 40 | Bommer Engineering Co. | San Antonio, TX 78260 | Oil & Gas Operator | May 2025 |
| 41 | Bosco Petroleum LLC | Muenster, TX 76252 | Oil Operator | May 2025 |
| 42 | Bowman, Fred Inc. | Dallas, TX 75225 | Oil & Gas Operator | Feb 2014 |
| 43 | Brammer Engineering, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | May 2025 |
| 44 | Brenham Drilling Co. | Flatonia, TX 78941 | Oil & Gas Operator | May 2025 |
| 45 | Bridge Oil Company LP | Midland, TX 79702 | Oil & Gas Operator | May 1999 |
| 46 | Bridwell Oil Company | Wichita Falls, TX 76307 | Oil & Gas Operator | May 2025 |
| 47 | Brittany Drilling Co. | Abilene, TX 79604 | Oil & Gas Operator | Dec 2000 |
| 48 | Broman Oil & Gas LP | Fort Worth, TX 76102 | Oil & Gas Operator | May 2017 |
| 49 | Browning Oil Company, Inc. | Dallas, TX 75251 | Oil & Gas Operator | May 2025 |
| 50 | Buckeye Energy Inc | Midland, TX 79702 | Oil & Gas Operator | Dec 2018 |
| 51 | C S J, Inc. | Austin, TX 78716 | Oil & Gas Operator | May 2025 |
| 52 | Cag Petroleum Corp. | Dallas, TX 75382 | Oil & Gas Operator | May 2025 |
| 53 | Cambrian Management LTD | McCaulley, TX 79534 | Oil & Gas Operator | May 2025 |
| 54 | Cameron, Paul E., Jr., Inc. | Montgomery, TX 77356 | Oil & Gas Operator | May 2015 |
| 55 | Cannan, Morris | San Antonio, TX 78205 | Oil & Gas Operator | May 2025 |
| 56 | Celero Energy LP | Midland, TX 79701 | Oil & Gas Operator | May 2011 |
| 57 | Central Plains Oil&Gas Corp. (A) | Bryan, TX 77802 | Oil & Gas Operator | Mar 2003 |
| 58 | Champlin Exploration, Inc. | Enid, OK 73702 | Oil & Gas Operator | Mar 2025 |
| 59 | Chaparral Energy, L.L.C. | Oklahoma City, OK 73142 | Oil & Gas Operator | May 2025 |
| 60 | Chesapeake Operating LLC | Oklahoma City, OK 73154 | Oil & Gas Operator | May 2025 |
| 61 | Chmelar, Eugene Oil & Gas | Caldwell, TX 77836 | Oil & Gas Operator | May 2025 |
| 62 | Cirrus Production Company | Enid, OK 73702 | Oil & Gas Operator | Feb 2025 |
| 63 | Clay Exploration, Inc. | Spring, TX 77387 | Oil & Gas Operator | Jun 2019 |
| 64 | CML Exploration, LLC | Austin, TX 78746 | Oil & Gas Operator | May 2025 |
| 65 | Coates Energy Trust | San Antonio, TX 78209 | Oil & Gas Operator | Aug 2008 |
| 66 | Columbia Gas Development Corp. | Houston, TX 77251 | Oil & Gas Operator | Jun 1996 |
| 67 | Comet Oil & Gas, Inc. | Conroe, TX 77305 | Oil & Gas Operator | May 2025 |
| 68 | Concord Operating Incorporated | Horseshoe Bay, TX 78657 | Oil & Gas Operator | Dec 2008 |
| 69 | Convest Energy Corporation | Houston, TX 77057 | Oil & Gas Operator | Sep 2014 |
| 70 | Copestone Operating, LLC | Houston, TX 77019 | Oil & Gas Operator | May 2025 |
| 71 | Core E & P Corp. | Victoria, TX 77902 | Oil & Gas Operator | May 2025 |
| 72 | Costilla Energy Inc | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 73 | Costilla Petroleum Corporation | Midland, TX 79702 | Oil & Gas Operator | Mar 2015 |
| 74 | County Management, Inc. | Houston, TX 77055 | Oil & Gas Operator | Apr 1993 |
| 75 | Creative Oil & Gas Operating,LLC | Giddings, TX 78942 | Oil & Gas Operator | May 2024 |
| 76 | Crescent Exploration Company | Austin, TX 78767 | Oil & Gas Operator | Aug 1995 |
| 77 | Crescent Pass Energy, LLC | Houston, TX 77070 | Oil & Gas Operator | May 2025 |
| 78 | Crest Resources Inc | Tulsa, OK 74103 | Oil & Gas Operator | May 2025 |
| 79 | CRM Energy, Inc. | Oklahoma City, OK 73101 | Oil & Gas Operator | May 2025 |
| 80 | Crownquest Operating, LLC | Midland, TX 79710 | Oil & Gas Operator | May 2025 |
| 81 | D. O. G. Operating, LLC | Port Aransas, TX 78373 | Oil & Gas Operator | May 2025 |
| 82 | Dallas Petroleum Group, LLC | Dallas, TX 75379 | Oil & Gas Operator | May 2025 |
| 83 | Daniels Petroleum Co | Denver, CO 80202 | Oil & Gas Operator | Mar 2003 |
| 84 | DCP Operating Co LP | Houston, TX 77042 | Oil & Gas Operator | Feb 2025 |
| 85 | Delaware Ecco Petroleum Inc. | Rockwall, TX 75087 | Oil & Gas Operator | Jul 2001 |
| 86 | Digital Operating Company LLC | Boerne, TX 78006 | Oil & Gas Operator | May 2025 |
| 87 | Dime Box Oil Company | Austin, TX 78759 | Oil & Gas Operator | Mar 2008 |
| 88 | Discorbis Oil Company | San Antonio, TX 78217 | Oil & Gas Operator | Jul 2019 |
| 89 | Dominion Oklahoma Texas E&P, Inc | Richmond, VA 23219 | Oil & Gas Operator | Sep 2018 |
| 90 | Douglas Petroleum Inc. | Spring, TX 77379 | Oil & Gas Operator | Nov 2010 |
| 91 | Dreyfus, Louis Natural Gas Corp | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2001 |
| 92 | Dynamic Petroleum Res., Inc. | Houston, TX 77068 | Oil & Gas Operator | Jul 1994 |
| 93 | Dynamic Production, Inc. | Fort Worth, TX 76106 | Oil & Gas Operator | May 2025 |
| 94 | E & G Wells Rehab Project LLC | Houston, TX 77071 | Oil Operator | May 2025 |
| 95 | E P C Oil & Gas, Inc. | Caldwell, TX 77836 | Oil & Gas Operator | May 2025 |
| 96 | E.G. Operating | Dallas, TX 75206 | Oil & Gas Operator | Mar 2008 |
| 97 | E.G.L. Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Mar 2025 |
| 98 | Eagle Ford Hunter Resources,Inc. | Houston, TX 77024 | Oil & Gas Operator | Apr 2013 |
| 99 | Eland Energy Inc | Dallas, TX 75248 | Oil & Gas Operator | Mar 2025 |
| 100 | Emerald Operating Company | Plano, TX 75075 | Oil & Gas Operator | Mar 2025 |