| 1 | 2 D Oil & Gas LLC | Refugio, TX 78377 | Oil & Gas Operator | Mar 2025 |
| 2 | 2 R Operating Co. | Paradise, TX 76073 | Oil & Gas Operator | Dec 2017 |
| 3 | 2 S Operating | Iowa Park, TX 76367 | Oil Operator | Sep 2018 |
| 4 | 2 T Production | Bowie, TX 76230 | Oil & Gas Operator | Mar 2025 |
| 5 | 2 W Petroleum | Brownwood, TX 76804 | Oil & Gas Operator | Mar 2025 |
| 6 | 2-J Operating | Iowa Park, TX 76367 | Oil Operator | Dec 2004 |
| 7 | 2-K Operating | Corsicana, TX 75109 | Oil & Gas Operator | Mar 2023 |
| 8 | 20TH Century Pipe & Equip.Co.Inc | Midland, TX 79702 | Oil & Gas Operator | Aug 2003 |
| 9 | 212 Operating Inc | Byron, OK 73722-9528 | Oil & Gas Operator | Jan 2016 |
| 10 | 21ST Century Investment Co | Tulsa, OK 74114-4220 | Oil & Gas Operator | Jan 2025 |
| 11 | 21ST Century Investment Corp | Tulsa, OK 74114 | Oil & Gas Operator | Apr 2000 |
| 12 | 21ST Century Oil Operations | Gorham, KS 67647 | Oil Operator | Dec 2001 |
| 13 | 25 Hill Properties Inc. | | Oil Operator | Dec 2024 |
| 14 | 260 Resource Management LLC | | Gas Operator | Dec 2024 |
| 15 | 261 Resource Management LLC | | Gas Operator | Dec 2024 |
| 16 | 27:17 Enterprises, LLC | Seminole, TX 79360 | Oil Operator | Mar 2025 |
| 17 | 299 Production, LLC | Judson, TX 75660 | Oil & Gas Operator | Nov 2016 |
| 18 | 2C Oil And Gas, LLC | Arp, TX 75750 | Oil Operator | Mar 2025 |
| 19 | 2MC Consulting LLC | San Angelo, TX 76901 | Oil Operator | Mar 2025 |
| 20 | 2R Oil, LLC | Sedan, KS 67361 | Oil Operator | Nov 2024 |
| 21 | 2S Resources LLC | Boerne, TX 78006 | Oil & Gas Operator | Mar 2025 |