| 1 | Kaiser-Francis Oil Company | Tulsa, OK 74121 | Oil & Gas Operator | Dec 2025 |
| 2 | Kalstra Energy LTD | Denver, CO 80222-5938 | Gas Operator | Jun 2018 |
| 3 | Kandletop Operating, LLC | Oklahoma City, OK 73106 | Oil & Gas Operator | Aug 2025 |
| 4 | Kay County Properties | Tulsa, OK 74145 | Oil & Gas Operator | May 1997 |
| 5 | KCS Medallion Resources, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Nov 2018 |
| 6 | KCS Resources LLC | Houston, TX 77027 | Oil & Gas Operator | Feb 2017 |
| 7 | Keith F Walker Oil & Gas Company LLC | Oklahoma City, OK 73114 | Oil & Gas Operator | Sep 2025 |
| 8 | Kelley Oil & Gas | McAlester, OK 74570 | Oil & Gas Operator | May 2013 |
| 9 | Kelloil Inc | Fort Worth, TX 76116-5600 | Oil & Gas Operator | Mar 2015 |
| 10 | Kerr McGee Rocky MTN Corp | Denver, CO 80202-5736 | Oil & Gas Operator | Mar 2015 |
| 11 | Kerr-McGee Corporation | Dallas, TX 75380 | Oil & Gas Operator | Aug 2025 |
| 12 | Kerr-McGee Oil & Gas Onshore LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2017 |
| 13 | Kerr-McGee Oil & Gas Onshore LP | Houston, TX 77046 | Oil & Gas Operator | Dec 2025 |
| 14 | Kerr-McGee Refining Corp | Oklahoma City, OK 73125 | Oil & Gas Operator | Jun 2007 |
| 15 | Kingery Drilling Co., Inc. | Ardmore, OK 73402 | Oil & Gas Operator | Sep 2025 |
| 16 | Klabzuba Oil & Gas Inc | Denver, CO 80202 | Oil & Gas Operator | Aug 2012 |
| 17 | Klo LLC | Tulsa, OK 74120-2428 | Oil & Gas Operator | Sep 2025 |
| 18 | KWB Oil Property Management Inc | Tulsa, OK 74103 | Oil & Gas Operator | Aug 2025 |