| 7001 | Crupper Operating & Trading Company | | Oil & Gas Operator | Dec 1996 |
| 7002 | Crusader Energy Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | Sep 2011 |
| 7003 | Crusader Energy Group Inc. | Austin, TX 78746 | Oil & Gas Operator | Mar 2015 |
| 7004 | Crusader Energy Group LLC | Oklahoma City, OK 73142 | Oil & Gas Operator | Mar 2015 |
| 7005 | Crusader Energy II LLC | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2015 |
| 7006 | Crusader Energy III LLC | Oklahoma City, OK 73142-1856 | Oil & Gas Operator | Feb 2011 |
| 7007 | Crusader Resources LC | Sugar Land, TX 77479 | Oil Operator | Mar 2026 |
| 7008 | Crusher Oil Company | Ponca City, OK 74604-5612 | Oil Operator | Apr 2017 |
| 7009 | Crutcher Oil Properties | Wichita Falls, TX 76301 | Oil & Gas Operator | Mar 2026 |
| 7010 | Cruthird, Mark Oil | Wichita Falls, TX 76308 | Oil & Gas Operator | Mar 2026 |
| 7011 | Cruzen Drilling Company Inc | Cleveland, OK 74020-0470 | Oil Operator | Nov 2014 |
| 7012 | Crystal Carbon Company | | Gas Operator | Dec 1930 |
| 7013 | Crystal Energy Inc | Oklahoma City, OK 73116 | Oil & Gas Operator | Feb 2019 |
| 7014 | Crystal Exploration & Production Company | Shreveport, LA 71120 | Oil & Gas Operator | Feb 1995 |
| 7015 | Crystal Exploration Co | | Oil & Gas Operator | Dec 2009 |
| 7016 | Crystal Gas, L.L.C. | | Oil & Gas Operator | Apr 2000 |
| 7017 | Crystal Oil And Land Company | | Oil & Gas Operator | May 1992 |
| 7018 | Crystal Oil Company | Shreveport, LA 71120 | Oil & Gas Operator | Jul 1995 |
| 7019 | Crystal River Oil & Gas LLC | Snowmass VLG., CO 81615 | Oil & Gas Operator | Jan 2023 |
| 7020 | Csa Exploration Company, Inc. | Houston, TX 77027 | Oil & Gas Operator | Aug 2003 |
| 7021 | Csapo Limited | Creston, OH 44217 | Oil & Gas Operator | Dec 2012 |
| 7022 | CSC Energy Corp. | | Oil & Gas Operator | Dec 2009 |
| 7023 | CSC, Inc. | | Oil Operator | Jan 2000 |
| 7024 | CSD IV Oil LLC | Columbus, OH 43209 | Oil Operator | Dec 2024 |
| 7025 | CSL Exploration, LP | Houston, TX 77002 | Oil & Gas Operator | Apr 2018 |
| 7026 | CSM, Inc. | | Gas Operator | Oct 1990 |
| 7027 | Cso Consulting | Bridgeport, TX 76426 | Oil & Gas Operator | Mar 2020 |
| 7028 | Csoda Operating Company LLC | Amarillo, TX 79114-7506 | Oil & Gas Operator | Aug 2021 |
| 7029 | CSV Holdings, Inc. | | Oil & Gas Operator | Dec 2014 |
| 7030 | CSX Oil & Gas Corporation | Houston, TX 77210-4326 | Oil & Gas Operator | Mar 1993 |
| 7031 | CT Adams Jr., LLC | Schulenburg, TX 78956 | Oil Operator | Mar 2026 |
| 7032 | CTC Oil Co., Inc. | Breckenridge, TX 76424 | Oil & Gas Operator | Mar 2026 |
| 7033 | Cti Associates | | Gas Operator | Jan 1990 |
| 7034 | CTL Oil & Gas Corporation | Buchanan Dam, TX 78609 | Oil & Gas Operator | Nov 2020 |
| 7035 | CTL Production, Inc. | Muenster, TX 76252 | Oil & Gas Operator | Mar 2026 |
| 7036 | CTR 247 LLC | Peru, KS 67360 | Oil Operator | Jul 2025 |
| 7037 | CTR Petroleum, Inc. | Corpus Chrsti, TX 78414 | Oil & Gas Operator | Mar 2015 |
| 7038 | CTX Energy Corporation | Dallas, TX 75206 | Oil & Gas Operator | Aug 2003 |
| 7039 | Cuatro Oil And Gas Corporation | Abilene, TX 79603 | Oil & Gas Operator | Mar 2026 |
| 7040 | Cuatro Petro Corp. | Richardson, TX 75080 | Oil & Gas Operator | Mar 2026 |
| 7041 | Cub Creek Energy LLC | | Oil & Gas Operator | Mar 2019 |
| 7042 | Cuba, John H. | Olney, TX 76374 | Oil Operator | Mar 2026 |
| 7043 | Cucharas Oil & Gas Company | Dallas, TX 75225 | Oil & Gas Operator | Dec 2000 |
| 7044 | Cudd Operating Corp | Oklahoma City, OK 73118 | Oil & Gas Operator | Apr 2020 |
| 7045 | Cuervo Resources, Inc. | FT Stockton, TX 79735 | Oil & Gas Operator | Oct 1996 |
| 7046 | Cuervo, Inc. | FT Stockton, TX 79735 | Oil & Gas Operator | Mar 2026 |
| 7047 | Cuesta Petroleum Inc | Shawnee, OK 74801-6963 | Oil & Gas Operator | Dec 2025 |
| 7048 | Culbreath Oil & Gas Co Inc | Tulsa, OK 74135 | Oil & Gas Operator | Jan 2026 |
| 7049 | Culebra Oil & Gas Company | Dallas, TX 75225 | Oil & Gas Operator | Dec 2000 |
| 7050 | Culebra Oil & Gas, LLC | Kerrville, TX 78028 | Oil & Gas Operator | Mar 2026 |
| 7051 | Cullen Corporati | | Oil & Gas Operator | Jan 1993 |
| 7052 | Cullison, Jimmie I. | Moscow, KS 67952 | Oil Operator | Apr 2002 |
| 7053 | Culoco, Inc. | Dallas, TX 75374 | Oil & Gas Operator | Nov 2024 |
| 7054 | Culp & Copple Oil Company | Cushing, OK 74023 | Oil & Gas Operator | Nov 2025 |
| 7055 | Culver & Cain Production LLC | Tyler, TX 75711 | Oil & Gas Operator | Mar 2026 |
| 7056 | Culver & Grounds | | Oil & Gas Operator | Nov 1995 |
| 7057 | Culver & Grounds Oil Properties, Inc. | McPherson, KS 67460 | Oil Operator | Sep 2025 |
| 7058 | Cumberland Exploration | Cleveland, OH 44111 | Oil & Gas Operator | Dec 1985 |
| 7059 | Cumberland Gas Co.(Tree Preservation Co) | | Oil & Gas Operator | Dec 1996 |
| 7060 | Cumberland Harlan Expl Corp | Barbourville, KY 40906 | Oil & Gas Operator | Dec 2024 |
| 7061 | Cumberland Operating Company | Seminole, OK 74868-1258 | Oil & Gas Operator | Mar 2007 |
| 7062 | Cumberland Operating LLC | Cody, WY 82414 | Oil & Gas Operator | Jan 2026 |
| 7063 | Cumberland Petroleum, Inc. II | Weatherford, TX 76086 | Oil & Gas Operator | May 1997 |
| 7064 | Cumberland River Oil & Gas, Inc | Williamsburg, KY 40769 | Oil & Gas Operator | Dec 2024 |
| 7065 | Cumberland Valley Resources, LLC | Louisville, KY 40204 | Oil & Gas Operator | Dec 2024 |
| 7066 | Cumming Company, Inc. The | Fort Worth, TX 76116 | Oil & Gas Operator | Mar 2026 |
| 7067 | Cummings Gene | | Oil Operator | Dec 2000 |
| 7068 | Cummings Oil & Cattle | Ada, OK 74820-0994 | Oil Operator | Jan 2017 |
| 7069 | Cummings Oil Company | Oklahoma City, OK 73112-6113 | Oil & Gas Operator | Jan 2026 |
| 7070 | Cummings, C. M. Oil & Gas | Lewisville, TX 75029 | Oil & Gas Operator | Nov 1993 |
| 7071 | Cummins & Walker Oil Co., Inc. | Austin, TX 78746 | Oil & Gas Operator | Jan 2021 |
| 7072 | Cummins Wren Oil Company | Tulsa, OK 74135 | Oil & Gas Operator | Nov 1998 |
| 7073 | Cundiff Harold | Perkins, OK 74059-4199 | Oil & Gas Operator | Dec 2025 |
| 7074 | Cundiff Jack | Perkins, OK 74059-4198 | Oil & Gas Operator | Apr 2014 |
| 7075 | Cundiff Operating Company | Dallas, TX 75238 | Oil & Gas Operator | Mar 2026 |
| 7076 | Cunningham Crude, A General Partnership | Independence, KS 67301 | Oil Operator | Sep 2025 |
| 7077 | Cunningham Energy LLC | Charleston, WV 25302 | Oil & Gas Operator | Dec 2021 |
| 7078 | Cunningham, Melvin | Medicine Lodge, KS 67104 | Oil Operator | Jan 2013 |
| 7079 | Cur-Ric Petrol & Gas Corp | Las Vegas, NV 89120-4003 | Oil Operator | Dec 1985 |
| 7080 | Curmar Producers | Adairsville, GA 30103 | Oil Operator | Mar 2008 |
| 7081 | Curn Lisa | Steubenville, OH 43952-2535 | Oil Operator | Dec 2025 |
| 7082 | Curran Oil Co | Great Falls, MT 59401 | Gas Operator | May 2001 |
| 7083 | Currie Cattle Co. | Big Spring, TX 79720 | Oil & Gas Operator | Sep 2007 |
| 7084 | Currie, V. Monta, Jr. | | Gas Operator | Nov 1990 |
| 7085 | Curry Oil | | Oil Operator | May 2005 |
| 7086 | Curry R D Production Co | Memphis, TN 38103 | Oil & Gas Operator | Dec 1986 |
| 7087 | Curry, Gregg | Madison, KS 66860 | Oil Operator | Sep 2025 |
| 7088 | Curt Weaver Et Al | | Oil Operator | Apr 1982 |
| 7089 | Curt'S Oil Opera | | Oil Operator | Nov 1994 |
| 7090 | Curt'S Oil Operation, LLC | Hoisington, KS 67544 | Oil & Gas Operator | Sep 2025 |
| 7091 | Curtis & Son Oil Inc | Sugar Grove, PA 16350 | Oil & Gas Operator | Dec 2025 |
| 7092 | Curtis Beard & Huston P. Ganey | | Oil Operator | Mar 1987 |
| 7093 | Curtis F. Adams | | Oil & Gas Operator | Oct 2024 |
| 7094 | Curtis Hankamer | Houston, TX 77024 | Oil & Gas Operator | Jun 1997 |
| 7095 | Curtis J Little | Farmington, NM 87499 | Oil & Gas Operator | Aug 2005 |
| 7096 | Curtis Oil Inc | Duke Center, PA 16729-0287 | Oil & Gas Operator | Dec 2025 |
| 7097 | Curzac Oil And Gas, LLC | Texarkana, TX 75503 | Oil & Gas Operator | Mar 2026 |
| 7098 | Curzon Operating Company LTD | Oklahoma City, OK 73118-4821 | Oil & Gas Operator | Dec 2025 |
| 7099 | Custer & Wright Operating, Inc. | Midland, TX 79702 | Oil & Gas Operator | Mar 2026 |
| 7100 | Custer K. Primos | | Oil & Gas Operator | Oct 2002 |