| 1 | Anderman/Smith Operating Company | Tulsa, OK 74136 | Oil & Gas Operator | Sep 1995 |
| 2 | Aroc (Texas) Inc. | Houston, TX 77090 | Oil & Gas Operator | Dec 2014 |
| 3 | Bay Rock Operating Company | San Antonio, TX 78212 | Oil & Gas Operator | Feb 2026 |
| 4 | Blackrock Operating, LLC | Tuscola, TX 79562 | Oil & Gas Operator | Feb 2026 |
| 5 | Bridge Oil Company LP | Midland, TX 79702 | Oil & Gas Operator | May 1999 |
| 6 | Browning & Welch, Inc | | Oil & Gas Operator | Mar 2005 |
| 7 | Carless Resources Inc | Cambridge, OH 43725 | Oil & Gas Operator | Dec 1997 |
| 8 | Cherry, Charles L. & Assoc., Inc. | | Oil & Gas Operator | Oct 1989 |
| 9 | Cleary Petroleum Corporation | Edmond, OK 73083 | Oil & Gas Operator | Jul 2019 |
| 10 | Deavours, Ruth | | Gas Operator | Sep 2003 |
| 11 | Enserch Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 12 | EP Operating Co. | Dallas, TX 75201 | Oil & Gas Operator | Jan 1993 |
| 13 | Finley Resources Inc | Fort Worth, TX 76113 | Oil & Gas Operator | Feb 2026 |
| 14 | Flare Inc | | Oil & Gas Operator | Jul 1995 |
| 15 | Germany Oil Company | Tulsa, OK 74135 | Oil & Gas Operator | Oct 2002 |
| 16 | Gibraltar Energy Co., Inc. & Richard H. Mason | | Gas Operator | Aug 1995 |
| 17 | Grace Petroleum Corp. | Tulsa, OK 74103 | Oil & Gas Operator | Oct 1997 |
| 18 | Howell Petroleum Corporation | Houston, TX 77251 | Oil & Gas Operator | Oct 2015 |
| 19 | Hughes Eastern Corporation | Ridgeland, MS 39157 | Oil & Gas Operator | Dec 2025 |
| 20 | Jabsco Oil Operating, LLC | Tuscaloosa, AL 35401 | Oil & Gas Operator | Dec 2025 |
| 21 | Justiss Oil Co Inc-Munoco Co | | Oil & Gas Operator | Dec 2008 |
| 22 | Justiss Oil Company, Inc. | Jena, LA 71342 | Oil & Gas Operator | Nov 2025 |
| 23 | Land And Natural Resource Development, Inc. | Northport, AL 35473 | Oil & Gas Operator | Dec 2025 |
| 24 | Michigan Oil Company | FT Worth, TX 76117 | Oil & Gas Operator | Feb 1998 |
| 25 | Moon-Hines-Tigrett Operating Co., Inc. | | Oil & Gas Operator | Dec 2025 |
| 26 | Morrow Oil & Gas Co. | Terry, MS 39170 | Oil & Gas Operator | Dec 2025 |
| 27 | MWJ Producing Company | Midland, TX 79701 | Oil & Gas Operator | Jul 1998 |
| 28 | Natural Gas & Oil, Inc. | Fayette, AL 35555 | Oil & Gas Operator | Dec 2025 |
| 29 | Pacific Enterprises Oil Co USA | Dallas, TX 75201 | Oil & Gas Operator | Feb 2001 |
| 30 | Petrus Oil Company, L.P. | | Oil & Gas Operator | Dec 1989 |
| 31 | Pride Energy Company | Tulsa, OK 74170 | Oil & Gas Operator | Feb 2026 |
| 32 | Pruet Production Co. | Jackson, MS 39201 | Oil & Gas Operator | Dec 2025 |
| 33 | Roundtree & Associates, Inc. | | Oil & Gas Operator | Jun 2024 |
| 34 | Samson Resources Company | Tulsa, OK 74103 | Oil & Gas Operator | Nov 2025 |
| 35 | Sanford Resources Corp. | | Oil & Gas Operator | Jul 1998 |
| 36 | Staghorn Resources, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2015 |
| 37 | Swift Energy Company | Houston, TX 77060 | Oil & Gas Operator | Mar 2021 |
| 38 | Terra Resources, Inc. | Casper, WY 82601 | Oil & Gas Operator | Jun 1990 |
| 39 | Txo Production Corp. | Ganado, TX 77962 | Oil & Gas Operator | Aug 2022 |
| 40 | Walter Black Warrior Basin LLC | | Gas Operator | Dec 2014 |
| 41 | Warrior Met Coal Gas, LLC | Brookwood, AL 35444 | Gas Operator | Dec 2025 |
| 42 | Yarberry, E. E. | Wichita Falls, TX 76308 | Oil & Gas Operator | Oct 2015 |