| 1 | D & A Oil Company | Abilene, TX 79606 | Oil & Gas Operator | Oct 2018 |
| 2 | D & A Oil Company, A General Partnership | Clearwater, KS 67026 | Oil Operator | Dec 2024 |
| 3 | D & B Gas Co. | Burden, KS 67019 | Gas Operator | Feb 2001 |
| 4 | D & D Energy | | Oil Operator | Jul 2023 |
| 5 | D & F Petroleum | | Oil & Gas Operator | Sep 1990 |
| 6 | D & G Oil Compan | | Oil Operator | Mar 1988 |
| 7 | D & J Investment | | Oil Operator | Jun 1995 |
| 8 | D & J Investments | | Oil Operator | Dec 2009 |
| 9 | D & J Oil Company | Kermit, TX 79745 | Oil & Gas Operator | Dec 2025 |
| 10 | D & L Energy | Morland, KS 67650 | Oil Operator | Mar 1995 |
| 11 | D & M Oil, Inc. | Winfield, KS 67156 | Oil Operator | Apr 2001 |
| 12 | D & R Oil Properties | | Oil Operator | May 1998 |
| 13 | D & R Oil, Inc. | Galva, KS 67443 | Oil & Gas Operator | Jul 2024 |
| 14 | D & R Well Service, Inc. | Galva, KS 67443 | Oil & Gas Operator | Jun 2025 |
| 15 | D & T Oil Company | Hays, KS 67601 | Oil Operator | Jun 2025 |
| 16 | D & W Oil Compan | | Oil Operator | Jan 1987 |
| 17 | D & Z Exploration, Inc. | St Elmo, IL 62458 | Oil Operator | Jun 2025 |
| 18 | D And B Oil | Midland, TX 79702 | Oil & Gas Operator | Dec 2025 |
| 19 | D J Oil Operations | | Oil Operator | Dec 2009 |
| 20 | D K Oil Services LLC | Wellsville, KS 66092 | Oil Operator | Nov 2019 |
| 21 | D Oil, Inc. | Victoria, KS 67671 | Oil Operator | Jun 2025 |
| 22 | D S & W Well Ser | | Oil Operator | Nov 1996 |
| 23 | D S & W Well Servicing, Inc. | Great Bend, KS 67530 | Oil & Gas Operator | Dec 2019 |
| 24 | D U Investments | Salina, KS 67401 | Oil & Gas Operator | Dec 2009 |
| 25 | D-Oil Incorporat | | Oil Operator | Aug 1990 |
| 26 | D. E. Exploration, Inc. | Wellsville, KS 66092 | Oil & Gas Operator | Jun 2025 |
| 27 | D. Jackson Rentals LLC | Easton, KS 66020 | Oil Operator | Jun 2025 |
| 28 | D. R. Lauck Oil Co., Inc. | Wichita, KS 67206 | Oil & Gas Operator | Jul 2019 |
| 29 | D.K. Rush Oil Co., LLC | El Dorado, KS 67042 | Oil Operator | Jun 2025 |
| 30 | D.M. Well Service | | Oil Operator | Dec 2019 |
| 31 | D.W.S. Properties | Sterling, KS 67579 | Oil Operator | Mar 2006 |
| 32 | Da Co Petroleum, Inc. | Wann, OK 74083 | Gas Operator | Apr 2003 |
| 33 | Da Company Petro | | Gas Operator | Jun 1995 |
| 34 | Da Energy, LLC | Lees Summit, MO 64063 | Oil Operator | Jun 2025 |
| 35 | Dakota Drilling, LLC | Wichita, KS 67205 | Oil Operator | Feb 2006 |
| 36 | Dakota Production Co., Inc. | Neodesha, KS 66757 | Gas Operator | May 2025 |
| 37 | Dakota Resources | | Oil & Gas Operator | Jan 1989 |
| 38 | Dale E. Jackson Production Co. | | Oil Operator | Jun 2025 |
| 39 | Dalen Resources Oil & Gas Co | Dallas, TX 75206 | Oil & Gas Operator | Jun 2010 |
| 40 | Dallas Production, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2021 |
| 41 | Damar Resc Incor | | Oil Operator | Oct 1995 |
| 42 | Damar Resources, Inc. | Hays, KS 67601 | Oil & Gas Operator | Apr 2025 |
| 43 | Damson Oil Corpo | | Oil & Gas Operator | May 1994 |
| 44 | Dane G. Hansen Trust | | Oil Operator | Dec 1994 |
| 45 | Daniels E L Dril | | Oil Operator | Nov 1995 |
| 46 | Daniels Oil Co. | | Oil Operator | Mar 2025 |
| 47 | Daniels Petroleu | | Oil Operator | Jan 1991 |
| 48 | Darco Petroleum Inc | Bartlesville, OK 74005 | Oil & Gas Operator | Dec 2020 |
| 49 | Dark Horse | | Oil Operator | Jun 2025 |
| 50 | Darnall, Walter E. | Chautauqua, KS 67334 | Oil Operator | Dec 2009 |
| 51 | Darrah John J Jr | | Oil & Gas Operator | Oct 1994 |
| 52 | Darrah John Jay Jr | Wichita, KS 67201 | Oil & Gas Operator | Sep 2025 |
| 53 | Darrah Oil Company, LLC | Wichita, KS 67201 | Oil & Gas Operator | Dec 2025 |
| 54 | Dart Cherokee Basin Operating Co., LLC | Mason, MI 48854 | Oil & Gas Operator | Jun 2025 |
| 55 | David D. Davis | Benton, KS 67017 | Oil Operator | Dec 2009 |
| 56 | Davies & Company Inc | Tulsa, OK 74114 | Oil & Gas Operator | Nov 2000 |
| 57 | Davis & Fitzgera | | Gas Operator | Dec 1983 |
| 58 | Davis Brothers O | | Oil Operator | Dec 1987 |
| 59 | Davis Contract Pumping | | Oil Operator | Oct 2000 |
| 60 | Davis Drilling & | | Oil Operator | Jul 1989 |
| 61 | Davis Oil Compan | | Oil Operator | Jul 1988 |
| 62 | Davis Operating Company | Elysian Field, TX 75642 | Oil & Gas Operator | Dec 2025 |
| 63 | Davis Petroleum | | Oil & Gas Operator | Dec 1996 |
| 64 | Davis Petroleum, Inc. | Great Bend, KS 67530 | Oil Operator | Aug 2021 |
| 65 | Davis, Billy F. | Tulsa, OK 74152 | Oil Operator | Jun 1988 |
| 66 | Davis, Michael G. | Wichita, KS 67212 | Oil & Gas Operator | Jul 1988 |
| 67 | Davis, Robert E. | Graham, TX 76450 | Oil & Gas Operator | Apr 1997 |
| 68 | Davis, Robert W. | Richfield, KS 67953 | Gas Operator | Dec 2010 |
| 69 | Davis, Travis H., Gas Account | Borger, TX 79008 | Gas Operator | Feb 2015 |
| 70 | Davis, W.C. Oil Company | Pratt, KS 67124 | Gas Operator | Nov 2008 |
| 71 | Davis, William H. | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2014 |
| 72 | Dawson Resources Inc | Franktown, CO 80116 | Oil & Gas Operator | Mar 2015 |
| 73 | Dawson-Markwell | | Oil & Gas Operator | Nov 1996 |
| 74 | Dawson-Markwell Exploration Co. | Oklahoma City, OK 73101 | Oil & Gas Operator | Sep 2025 |
| 75 | Daylight Petroleum LLC | Houston, TX 77052 | Oil & Gas Operator | Dec 2025 |
| 76 | Daystar Petroleum Inc | Eureka, KS 67045 | Oil & Gas Operator | Jun 2025 |
| 77 | DB Energy, LLC | Baldwin City, KS 66006 | Oil Operator | May 2025 |
| 78 | DBD Oil, LLC | Emporia, KS 66801 | Oil Operator | Jun 2025 |
| 79 | DCF Exploration | Lakewood, CO 80215 | Oil Operator | Dec 1989 |
| 80 | DCP Midstream, LP | Denver, CO 80237 | Oil Operator | Nov 2006 |
| 81 | De & TZ LLC | Wellsville, KS 66092 | Oil Operator | Jun 2025 |
| 82 | Dearinger Compan | | Oil Operator | Dec 1994 |
| 83 | Decab Company | Victoria, KS 67671 | Oil Operator | Aug 1996 |
| 84 | Dechant Oil Operations, LLC | Hutchinson, KS 67501 | Oil Operator | Jun 2025 |
| 85 | Deck Oil Company | Tulsa, OK 74101 | Oil & Gas Operator | Jun 2020 |
| 86 | Decker Lease Ope | | Oil Operator | Dec 1988 |
| 87 | Decker Petroleum | | Oil & Gas Operator | Oct 2002 |
| 88 | Deer Run Oil Lease, LLC | Caney, KS 67333 | Oil Operator | Jun 2025 |
| 89 | Delaware Dyche Corp. | Hutchinson, KS 67501 | Oil Operator | Jan 2010 |
| 90 | Delhi Gas Pipeli | | Gas Operator | Aug 1998 |
| 91 | Delhi Pipeline | | Oil & Gas Operator | Sep 1999 |
| 92 | Dell-Ray Investments, Inc. | Nickerson, KS 67561 | Oil Operator | Dec 2019 |
| 93 | Delozier, Orval & Stevens, Floyd, A General Partnership | Dewey, OK 74029 | Oil Operator | Nov 2009 |
| 94 | Delta Petroleum Company | Houston, TX 77267 | Oil Operator | Aug 1996 |
| 95 | Delta Petroleum Corp | Denver, CO 80202 | Oil & Gas Operator | Dec 2024 |
| 96 | Deltex Petroleum | | Oil Operator | Nov 1994 |
| 97 | Denchfield, Fred | Neal, KS 66863 | Oil Operator | Dec 1997 |
| 98 | Denis Roberts Oil | | Oil Operator | May 2025 |
| 99 | Denman J M Oil C | | Oil Operator | Mar 1994 |
| 100 | Denmark Oil | Wichita, KS 67212 | Oil & Gas Operator | May 2000 |