| 1 | Abaco Operating, LLC | San Antonio, TX 78209 | Oil & Gas Operator | May 2025 |
| 2 | Abraxas Petroleum Corporation | San Antonio, TX 78259 | Oil & Gas Operator | May 2025 |
| 3 | Ac Exploration, LLC | Houston, TX 77024 | Oil & Gas Operator | May 2025 |
| 4 | Acco Oil & Gas Company | Houston, TX 77056 | Oil & Gas Operator | Sep 2001 |
| 5 | Acock Engineering & Assoc., Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Jul 2002 |
| 6 | Acock Operating Limited | San Antonio, TX 78270 | Oil & Gas Operator | May 2025 |
| 7 | Acock/Anaqua Operating Co., LC | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Apr 2004 |
| 8 | Acock/Anaqua Operating Co., LP | Corpus Chrsti, TX 78401 | Oil & Gas Operator | May 2025 |
| 9 | Acoma Oil Corporation | Saint Paul, MN 55102 | Oil & Gas Operator | May 2025 |
| 10 | Adobe Energy, Inc. | The Woodlands, TX 77380 | Oil & Gas Operator | Nov 2004 |
| 11 | Advantage Oil & Gas, Inc. | Pinehurst, TX 77362 | Oil & Gas Operator | May 2025 |
| 12 | Aikman Oil Corp. | Oklahoma City, OK 73157 | Oil & Gas Operator | May 2025 |
| 13 | Albrecht, Phil A., Jr. | Victoria, TX 77901 | Oil & Gas Operator | Jun 2005 |
| 14 | Alexander, Herbert R. Inc. | Houma, LA 70360 | Oil & Gas Operator | Jun 1998 |
| 15 | Allegro Investments, Inc. | Victoria, TX 77903 | Oil & Gas Operator | Nov 2020 |
| 16 | Alta Mesa Services, LP | Houston, TX 77084 | Oil & Gas Operator | May 2025 |
| 17 | Amax Oil & Gas Inc | Fort Worth, TX 76107 | Oil & Gas Operator | Nov 2014 |
| 18 | Amend Energy Company | Houston, TX 77227 | Oil & Gas Operator | Apr 2002 |
| 19 | Amerada Hess Corporation | Houston, TX 77252 | Oil & Gas Operator | Aug 2013 |
| 20 | American Cometra, Inc. | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2008 |
| 21 | American Energy Partners Inc | Boerne, TX 78006 | Oil & Gas Operator | Dec 2011 |
| 22 | American Int'L Energy Corp. | Houston, TX 77057 | Oil & Gas Operator | Aug 2019 |
| 23 | American National Petroleum Co. | Houston, TX 77057 | Oil & Gas Operator | Aug 1995 |
| 24 | American Pumping & Trucking | New Braunfels, TX 78131 | Oil & Gas Operator | May 2025 |
| 25 | Americo Energy Resources, LLC | Houston, TX 77063 | Oil & Gas Operator | May 2025 |
| 26 | Amexco, LLC | San Antonio, TX 78259 | Oil & Gas Operator | May 2025 |
| 27 | Amoco Production Co. | Houston, TX 77253 | Oil & Gas Operator | Jun 2015 |
| 28 | Amtex Energy, Inc. | Fort Worth, TX 76147 | Oil & Gas Operator | May 2025 |
| 29 | Anaqua Oil & Gas, Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Mar 2008 |
| 30 | Anderson Petro-Equipment, Inc. | Montgomery, TX 77356 | Oil & Gas Operator | May 2025 |
| 31 | Anderson Producing, Inc. | Houston, TX 77057 | Oil & Gas Operator | Sep 2013 |
| 32 | Apache Corporation | Houston, TX 77042 | Oil & Gas Operator | May 2025 |
| 33 | Aquinas Oil & Gas, LLC | Muenster, TX 76252 | Oil Operator | May 2025 |
| 34 | Arco Oil & Gas Company | Plano, TX 75086 | Oil & Gas Operator | Mar 2006 |
| 35 | Arkla Exploration Co. | Shreveport, LA 71151 | Oil & Gas Operator | Jan 1993 |
| 36 | Armour Resource Holdings, LTD. | Houston, TX 77046 | Oil & Gas Operator | Nov 1994 |
| 37 | Arrington,David H. Oil & Gas,Inc | Midland, TX 79702 | Oil & Gas Operator | May 2025 |
| 38 | Arriola Operating & Consltg Inc. | Dallas, TX 75248 | Oil Operator | May 2025 |
| 39 | Ascent Energy, Inc | McKinney, TX 75069 | Oil & Gas Operator | Nov 2008 |
| 40 | Ascent Operating, LP | Plano, TX 75093 | Oil & Gas Operator | Aug 2008 |
| 41 | Ashland Exploration Inc | Houston, TX 77218 | Oil & Gas Operator | Nov 2000 |
| 42 | Aspect Resources LLC | Denver, CO 80202 | Oil & Gas Operator | May 2002 |
| 43 | Atapco | Houston, TX 77040 | Oil & Gas Operator | Feb 1999 |
| 44 | Atasca Resources Inc | Houston, TX 77219 | Oil & Gas Operator | May 2025 |
| 45 | Atlas Operating LLC | Houston, TX 77056 | Oil & Gas Operator | May 2025 |
| 46 | Atoka Operating, Inc. | Gainesville, TX 76241 | Oil & Gas Operator | May 2025 |
| 47 | Aurora Resources Corporation | Corpus Chrsti, TX 78401 | Oil & Gas Operator | May 2025 |
| 48 | B & B Drilling Co. | Milano, TX 76556 | Oil & Gas Operator | Jul 2015 |
| 49 | B & G Energy Corporation | Dallas, TX 75214 | Oil & Gas Operator | May 2025 |
| 50 | B & M Operating Co., Inc. | Houston, TX 77006 | Oil & Gas Operator | May 2025 |
| 51 | B.N.B. Production Inc. | Austin, TX 78720 | Oil & Gas Operator | May 1996 |
| 52 | B.P. Productions Inc. | Victoria, TX 77904 | Oil & Gas Operator | May 2025 |
| 53 | Ballard Exploration Company,Inc. | Houston, TX 77002 | Oil & Gas Operator | May 2025 |
| 54 | Bargo Energy Company | Houston, TX 77010 | Oil & Gas Operator | May 2001 |
| 55 | Bass Enterprises Production Co | Fort Worth, TX 76102 | Oil & Gas Operator | Dec 2006 |
| 56 | Bay Rock Operating Company | San Antonio, TX 78212 | Oil & Gas Operator | May 2025 |
| 57 | Baylor Operating, LLC | Austin, TX 78766 | Oil & Gas Operator | May 2025 |
| 58 | Beard Oil Company, LLC | Edna, TX 77957 | Oil & Gas Operator | May 2025 |
| 59 | Bellows, Dewey Oper. Co., LTD. | Refugio, TX 78377 | Oil & Gas Operator | Jul 2013 |
| 60 | Bellwether Exploration Company | Houston, TX 77010 | Oil & Gas Operator | May 2001 |
| 61 | Bepco Operating Co. | Fort Worth, TX 76102 | Oil & Gas Operator | Oct 2006 |
| 62 | Bettis, Boyle & Stovall | Graham, TX 76450 | Oil & Gas Operator | May 2025 |
| 63 | BHP Petroleum (Americas) Inc | Houston, TX 77056 | Oil & Gas Operator | Mar 2015 |
| 64 | Billfisch Exploration Co., Inc. | Corpus Chrsti, TX 78473 | Oil & Gas Operator | Oct 1997 |
| 65 | Bison Energy Partners, Inc. | Houston, TX 77060 | Oil & Gas Operator | Sep 2001 |
| 66 | Bison Energy Partners, LTD. | Houston, TX 77060 | Oil & Gas Operator | Apr 2002 |
| 67 | Black Pearl Exploration, L.L.C. | Houston, TX 77095 | Oil & Gas Operator | May 2015 |
| 68 | Blue Ridge Group, Inc. | Bowling Green, KY 42101 | Oil & Gas Operator | Dec 2023 |
| 69 | BNP Petroleum Corporation | Corpus Chrsti, TX 78478 | Oil & Gas Operator | May 2025 |
| 70 | Boling Production Company, Inc. | Boling, TX 77420 | Oil & Gas Operator | May 2025 |
| 71 | Bommer Engineering Co. | San Antonio, TX 78260 | Oil & Gas Operator | May 2025 |
| 72 | Boney Enterprises Prod. Co. | Houston, TX 77055 | Oil & Gas Operator | May 2025 |
| 73 | Bowman, Fred Inc. | Dallas, TX 75225 | Oil & Gas Operator | Feb 2014 |
| 74 | Bozeman, John F. | Rosenberg, TX 77471 | Oil & Gas Operator | Sep 2005 |
| 75 | BP America Production Company | Denver, CO 80202 | Oil & Gas Operator | Feb 2025 |
| 76 | BP Prod. Corp. | Richardson, TX 75083 | Oil & Gas Operator | May 2025 |
| 77 | Braman, D. H., Jr. | Victoria, TX 77901 | Oil & Gas Operator | Dec 2008 |
| 78 | Brayton Operating Corp. | Corpus Chrsti, TX 78476 | Oil & Gas Operator | Sep 2009 |
| 79 | Bridge Oil Company LP | Midland, TX 79702 | Oil & Gas Operator | May 1999 |
| 80 | Bridge Oil Production Co., Inc. | Midland, TX 79702 | Oil & Gas Operator | Jun 1993 |
| 81 | Brothers Production Company Inc. | Midland, TX 79708 | Oil & Gas Operator | May 2025 |
| 82 | Brown Tom Inc | Dallas, TX 75240 | Oil & Gas Operator | Mar 2015 |
| 83 | Brown, C. Douglas, LLC | Dallas, TX 75209 | Oil & Gas Operator | Dec 2005 |
| 84 | Bruington Operating, L.L.C. | San Antonio, TX 78217 | Oil & Gas Operator | Apr 2015 |
| 85 | Bse Production Co. | Victoria, TX 77903 | Oil & Gas Operator | May 2025 |
| 86 | Bulldog Exploration, LP | Houston, TX 77090 | Oil & Gas Operator | Apr 2011 |
| 87 | Burlington Resources Oil & Gas Company LP | Houston, TX 77252 | Oil & Gas Operator | May 2025 |
| 88 | Burlington Resources Oil And Gas Co. | Houston, TX 77210 | Oil & Gas Operator | Mar 2023 |
| 89 | Buttes Resources Company | Houston, TX 77056 | Oil & Gas Operator | May 2007 |
| 90 | Bwab Incorporated | Denver, CO 80202 | Oil & Gas Operator | Aug 1996 |
| 91 | C & E Operating, Inc. | Hockley, TX 77447 | Oil & Gas Operator | May 2025 |
| 92 | C & M Operating, Inc. (A) | Alleyton, TX 78935 | Gas Operator | Aug 2011 |
| 93 | C5 Energy LLC | Collinsville, OK 74021 | Oil & Gas Operator | Dec 2019 |
| 94 | Calpine Natural Gas Company | Houston, TX 77002 | Oil & Gas Operator | Apr 2002 |
| 95 | Cameron Engineering, Inc | Montgomery, TX 77356 | Oil & Gas Operator | Jun 2003 |
| 96 | Cameron, Paul E., Jr., Inc. | Montgomery, TX 77356 | Oil & Gas Operator | May 2015 |
| 97 | Camoil, Inc. | Columbus, TX 78934 | Oil & Gas Operator | May 2025 |
| 98 | Campana Petroleum Company | Midland, TX 79705 | Oil & Gas Operator | May 2025 |
| 99 | Carrizo Oil & Gas, Inc. | Houston, TX 77002 | Oil & Gas Operator | May 2025 |
| 100 | Carter Exploration Company | Corpus Chrsti, TX 78413 | Oil & Gas Operator | Feb 2015 |