| 1 | K & D Operating Co. A | Gruver, TX 79040 | Oil & Gas Operator | Feb 2019 |
| 2 | K. Stewart Petroleum Corporation | Oklahoma City, OK 73103 | Oil & Gas Operator | Jun 2001 |
| 3 | K.M.A. Operating, Inc. | Graham, TX 76450 | Oil & Gas Operator | Aug 2003 |
| 4 | Kaiser-Francis Oil Company | Tulsa, OK 74121 | Oil & Gas Operator | Dec 2024 |
| 5 | Karper Oil & Gas Corporation | Graham, TX 76450 | Oil & Gas Operator | Dec 2024 |
| 6 | KCS Medallion Resources, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Nov 2018 |
| 7 | Kem Energy, Inc. | Katy, TX 77450 | Oil & Gas Operator | Dec 2024 |
| 8 | Kennedy & Mitchell, Inc. | Houston, TX 77084 | Oil & Gas Operator | Aug 2013 |
| 9 | Kerr-McGee Corporation | Dallas, TX 75380 | Oil & Gas Operator | Jun 2024 |
| 10 | Kerr-McGee Oil & Gas Onshore LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2017 |
| 11 | Kerr-McGee Oil & Gas Onshore LP | Houston, TX 77046 | Oil & Gas Operator | Dec 2024 |
| 12 | Key Energy Of Colorado, Inc. | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2016 |
| 13 | Kile Production | Cypress, TX 77410 | Oil & Gas Operator | Aug 2014 |
| 14 | Kimball Production Co. | Houston, TX 77042 | Oil & Gas Operator | Jul 2002 |
| 15 | Kimbell Oil Company Of Texas | Fort Worth, TX 76102 | Oil & Gas Operator | Oct 2024 |
| 16 | Kimbrel Oil Corporation | Tulsa, OK 74114 | Oil & Gas Operator | Dec 2024 |
| 17 | King Operating Corporation | Fort Worth, TX 76147 | Oil & Gas Operator | Dec 2024 |
| 18 | KRS Oil Company | Frisco, TX 75034 | Oil & Gas Operator | Apr 2020 |