| 1 | Abercrombie A L | | Oil & Gas Operator | Nov 1995 |
| 2 | Abraxas Petroleum Corporation | San Antonio, TX 78259 | Oil & Gas Operator | Oct 2025 |
| 3 | Beren Corporatio | | Oil & Gas Operator | Dec 1995 |
| 4 | Berry Petroleum Company | Denver, CO 80202 | Oil & Gas Operator | Feb 2014 |
| 5 | Black Oak Exploration, LLC | Denver, CO 80210 | Oil & Gas Operator | Jun 2025 |
| 6 | Chizum Oil LLC | Wichita, KS 67211 | Oil & Gas Operator | Jun 2025 |
| 7 | Foundation Energy Management, LLC | Addison, TX 75001 | Oil & Gas Operator | Oct 2025 |
| 8 | HG Oil Holdings, LLC | Hoisington, KS 67544 | Oil & Gas Operator | Jun 2025 |
| 9 | J-W Operating Company | Christoval, TX 76935 | Oil & Gas Operator | Oct 2025 |
| 10 | L. D. Drilling, Inc. | Great Bend, KS 67530 | Oil & Gas Operator | Jun 2025 |
| 11 | Lobo Production, Inc | Goodland, KS 67735 | Gas Operator | Jun 2025 |
| 12 | Marathon Oil Company | Houston, TX 77252 | Oil & Gas Operator | Aug 2025 |
| 13 | Murfin Drilling | | Oil & Gas Operator | Jul 1997 |
| 14 | Murfin Drilling Company Inc | Wichita, KS 67202 | Oil & Gas Operator | Aug 2025 |
| 15 | National Petroleum Reserves, Inc. | Wichita, KS 67206 | Oil & Gas Operator | Apr 2012 |
| 16 | Noble Energy Inc | Midland, TX 79706 | Oil & Gas Operator | Oct 2025 |
| 17 | Oil Producers, Inc. Of Kansas | Wichita, KS 67206 | Oil & Gas Operator | Oct 2025 |
| 18 | Own Resources Operating LLC | The Woodlands, TX 77381 | Oil & Gas Operator | Jul 2025 |
| 19 | Palomino Petroleum Inc | Newton, KS 67114 | Oil & Gas Operator | Jun 2025 |
| 20 | Ritchie Explorat | | Oil & Gas Operator | Dec 1996 |
| 21 | Rosewood Resources, Inc. | Dallas, TX 75201 | Oil & Gas Operator | Oct 2025 |
| 22 | Thoroughbred Associates L.L.C. | Wichita, KS 67226 | Oil & Gas Operator | Jun 2025 |
| 23 | Val Energy, Inc. | Wichita, KS 67202 | Oil & Gas Operator | Jun 2025 |