| 1 | K C S Michigan Resources Inc | | Oil & Gas Operator | Mar 2004 |
| 2 | Kaiser-Francis Oil Company | Tulsa, OK 74121 | Oil & Gas Operator | Dec 2025 |
| 3 | Kalkaska Oilfield Services Inc | | Oil Operator | Aug 2006 |
| 4 | Kasperski Oil Corp | | Oil & Gas Operator | May 2002 |
| 5 | KCS Resources, Inc. | Houston, TX 77002 | Oil & Gas Operator | Feb 2009 |
| 6 | Kelly James O | | Oil & Gas Operator | Apr 2000 |
| 7 | Kelly James O Dba Kelly Oil Co | | Oil & Gas Operator | Aug 1987 |
| 8 | Kelly Oil And Gas Inc | | Oil & Gas Operator | Mar 1999 |
| 9 | Kep Exploration Inc | | Oil & Gas Operator | Feb 1991 |
| 10 | Kep Exploration Inc And Haggard Ward M | | Oil & Gas Operator | Dec 1986 |
| 11 | Kimbark Oil & Gas Company | Denver, CO 80203 | Oil & Gas Operator | May 2007 |
| 12 | Kirby Exploration Co Of Texas | | Oil & Gas Operator | Nov 1993 |
| 13 | Klabzuba Oil & Gas Inc | Denver, CO 80202 | Oil & Gas Operator | Aug 2012 |
| 14 | Klingler Automatic Industries Inc | | Oil & Gas Operator | Sep 2025 |
| 15 | Koyl Oil Inc | | Oil & Gas Operator | Oct 2025 |
| 16 | Kughn | | Oil Operator | Sep 2019 |
| 17 | Kulka And Schmidt Inc | | Oil & Gas Operator | Dec 1992 |