| 4501 | C N Operating Co | Drumright, OK 74030 | Oil & Gas Operator | Nov 1998 |
| 4502 | C O Fulton | Artesia, NM 88211 | Oil & Gas Operator | Sep 2022 |
| 4503 | C O G Company | Bangs, TX 76823 | Oil & Gas Operator | Dec 2025 |
| 4504 | C Oil Co. | New Braunfels, TX 78132 | Oil & Gas Operator | Feb 2017 |
| 4505 | C R A C O Incorp | | Oil Operator | May 1988 |
| 4506 | C R I Inc | Midland, TX 79702 | Oil & Gas Operator | Nov 1993 |
| 4507 | C Rose Oil Co. | Midland, TX 79708 | Oil & Gas Operator | Aug 2025 |
| 4508 | C S J, Inc. | Austin, TX 78716 | Oil & Gas Operator | Dec 2025 |
| 4509 | C T R Resources Inc | Alliance, OH 44601 | Oil & Gas Operator | Dec 2013 |
| 4510 | C W Oil Producer | | Oil Operator | Oct 1998 |
| 4511 | C W Riggs Inc | St. Marys, WV 26170 | Oil & Gas Operator | Dec 1999 |
| 4512 | C W Trainer | Midland, TX 79702 | Oil & Gas Operator | Nov 2009 |
| 4513 | C&C II | Pleasanton, TX 78064 | Oil & Gas Operator | Mar 1998 |
| 4514 | C&D Management Company Dba Freedom Ventures | Las Vegas, NV 89149 | Oil & Gas Operator | Feb 2019 |
| 4515 | C&M Operating Company, LLC | | Oil & Gas Operator | Apr 2011 |
| 4516 | C&P Resources Operating Co,LLC | Houston, TX 77056 | Oil & Gas Operator | Dec 2025 |
| 4517 | C-D Oil Company, Inc. | Cameron, TX 76520 | Oil Operator | Dec 2025 |
| 4518 | C-V Oil Company | Memphis, TN 38103 | Oil Operator | Jun 1998 |
| 4519 | C-Water Disposal Inc | Oklahoma City, OK 73116-7326 | Oil Operator | Dec 2014 |
| 4520 | C. A. Cardneaux, Inc. | | Oil & Gas Operator | Apr 1990 |
| 4521 | C. C. Killingsworth Opr. | | Oil Operator | Dec 1999 |
| 4522 | C. Case Company | | Oil & Gas Operator | Oct 2025 |
| 4523 | C. D. Oil, Inc. | Wellsville, KS 66092 | Oil Operator | Dec 2009 |
| 4524 | C. D. Pierce | | Oil Operator | Mar 1991 |
| 4525 | C. E. Allen Co. Inc. | | Oil & Gas Operator | Sep 2025 |
| 4526 | C. E. Braly | | Oil & Gas Operator | Dec 1991 |
| 4527 | C. F. Oil, A General Partnership | Lake Lotawana, MO 64086 | Oil Operator | Jun 2025 |
| 4528 | C. F. Sudduth | | Oil & Gas Operator | Dec 1988 |
| 4529 | C. H. C. Gerard | | Oil & Gas Operator | Jan 2025 |
| 4530 | C. H. Cuatro | | Gas Operator | Sep 1996 |
| 4531 | C. H. Todd, Inc. | Wichita, KS 67212 | Oil & Gas Operator | Dec 2019 |
| 4532 | C. I. McKown & Son, Inc. | Newton, WV 25266-0711 | Oil & Gas Operator | Dec 2021 |
| 4533 | C. J. Broome Oil Company | | Oil & Gas Operator | Jan 2020 |
| 4534 | C. J. Filson, LLC | Protection, KS 67127 | Gas Operator | Aug 2014 |
| 4535 | C. J. Services | | Oil & Gas Operator | Sep 2016 |
| 4536 | C. L. Brown, III | | Oil Operator | Dec 1991 |
| 4537 | C. L. Brown, Inc. | | Oil Operator | Dec 1999 |
| 4538 | C. L. Morris | | Oil Operator | Feb 2004 |
| 4539 | C. L. Morris, Inc. | | Oil & Gas Operator | Feb 2004 |
| 4540 | C. M. Frizzell | | Oil & Gas Operator | Mar 2014 |
| 4541 | C. M. Oil Corporation | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Mar 2016 |
| 4542 | C. M. Roberson | | Oil Operator | Jun 1984 |
| 4543 | C. O. Oil And Gas, LLC | Pampa, TX 79066 | Oil & Gas Operator | Dec 2025 |
| 4544 | C. Smith & Associates, Inc. | | Oil Operator | Aug 1991 |
| 4545 | C. T. & Ted Paul | | Oil Operator | Mar 2019 |
| 4546 | C. V. Radke | | Oil Operator | Jan 1993 |
| 4547 | C. W. Brumley | | Oil & Gas Operator | Jun 2006 |
| 4548 | C. W. Resources, Inc. | Longview, TX 75604 | Oil & Gas Operator | Oct 2025 |
| 4549 | C. Wayland Brooks | | Oil & Gas Operator | Dec 1987 |
| 4550 | C.B.C. Producing Co. | | Oil & Gas Operator | Jul 1989 |
| 4551 | C.C.O. & G. Company Inc. | Austin, TX 78765 | Oil & Gas Operator | Sep 1995 |
| 4552 | C.F. Braun & Company | | Oil & Gas Operator | Dec 1986 |
| 4553 | C.F.D. Inc. | | Oil & Gas Operator | Nov 1988 |
| 4554 | C.F.O., Inc. | Liberty, TX 77575 | Oil Operator | Dec 2025 |
| 4555 | C.J. Oil Company | Iowa Park, TX 76367 | Oil Operator | Jan 2025 |
| 4556 | C.O.W. Operating Company | Graham, TX 76450 | Oil Operator | Dec 2025 |
| 4557 | C.P.I. | | Oil & Gas Operator | Oct 2007 |
| 4558 | C.S.V. Oil Exploration Co | West Jordan, UT 84088 | Gas Operator | Sep 2025 |
| 4559 | C.T.R. Oil, Inc. | | Oil & Gas Operator | Jan 2025 |
| 4560 | C.W. Pickering, Inc. | Victoria, TX 77904 | Gas Operator | Sep 2022 |
| 4561 | C.W.F.K., Inc. | | Gas Operator | Dec 1986 |
| 4562 | C12 Energy: North Dakota LLC | | Oil Operator | Apr 2017 |
| 4563 | C12 Kansas Oil, LLC | Denver, CO 80202 | Oil Operator | Dec 2009 |
| 4564 | C3oil, LLC | New Strawn, KS 66839 | Oil Operator | Jun 2025 |
| 4565 | C5 Energy LLC | Collinsville, OK 74021 | Oil & Gas Operator | Dec 2019 |
| 4566 | C6 Operating, L.L.C. | Keatchie, LA 71046 | Oil & Gas Operator | Dec 2025 |
| 4567 | Ca-Dora Inc | Waterford, OH 45786 | Oil & Gas Operator | Dec 1984 |
| 4568 | Caac 100 LLC | | Oil & Gas Operator | Oct 2025 |
| 4569 | Cab Resources, LLC | Odessa, TX 79762 | Oil Operator | Dec 2025 |
| 4570 | Caba, LLC | | Oil Operator | Jan 2025 |
| 4571 | Cabal Energy Corporation | Midland, TX 79701 | Oil & Gas Operator | Dec 2025 |
| 4572 | Caballero Operations LLC | | Oil & Gas Operator | Oct 2025 |
| 4573 | Cabana Oil Corp. | Abilene, TX 79608 | Oil & Gas Operator | Feb 2006 |
| 4574 | Cabco Energy Corporation | Hoffman, OK 74437 | Oil & Gas Operator | Dec 2018 |
| 4575 | Cabeza Oil And Gas, LLC | Austin, CO 81410 | Oil & Gas Operator | Mar 2022 |
| 4576 | Cable W S | Cleveland, OK 74020 | Oil Operator | Jan 2021 |
| 4577 | Cabot Exploration Corp | Houston, TX 77070 | Oil Operator | Jun 1999 |
| 4578 | Cabot Oil & Gas Corporation | Houston, TX 77024 | Oil & Gas Operator | Sep 2025 |
| 4579 | Cabot Oil & Gas Production Corp. | Houston, TX 77060 | Oil & Gas Operator | Jun 1996 |
| 4580 | Cabot Petroleum | | Oil & Gas Operator | Oct 1996 |
| 4581 | Cabot Petroleum Corporation | Englewood, CO 80111-2529 | Oil & Gas Operator | Dec 2004 |
| 4582 | Cactus Energy Company LLC | Hennessey, OK 73742 | Oil & Gas Operator | Oct 2025 |
| 4583 | Cactus Gas & Oil, Inc. | San Antonio, TX 78259 | Oil & Gas Operator | Dec 2025 |
| 4584 | Cactus Jack Operating Company | Carrizo SPGS, TX 78834 | Oil & Gas Operator | Aug 2003 |
| 4585 | Cactus Oil & Gas LLC | Seminole, OK 74868-2430 | Oil & Gas Operator | Mar 2018 |
| 4586 | Cactus Oil Company | Pampa, TX 79066 | Oil & Gas Operator | Aug 2000 |
| 4587 | Cactus Operating Company | Wichita Falls, TX 76301 | Oil & Gas Operator | Nov 2000 |
| 4588 | Cactus Operating Company, LLC | Lovington, NM 88260 | Oil & Gas Operator | Jul 2005 |
| 4589 | Cactus Petroleum Corporation | Houston, TX 77077 | Oil & Gas Operator | Dec 2025 |
| 4590 | Cad Energy Corporation | Creston, WV 26141 | Oil & Gas Operator | Dec 2021 |
| 4591 | Cada Operating, Inc. | Wichita Falls, TX 76307 | Oil & Gas Operator | Nov 2004 |
| 4592 | Caddeaux Gathering, LLC | | Oil Operator | Dec 2024 |
| 4593 | Caddell Well Service, Inc. | Prairie Lea, TX 78661 | Oil & Gas Operator | Dec 2025 |
| 4594 | Caddo Corporation | Austin, TX 78731 | Oil & Gas Operator | Dec 2025 |
| 4595 | Caddo Creek Corporation | Breckenridge, TX 76424 | Oil & Gas Operator | Dec 1994 |
| 4596 | Caddo Exploration, LLC | Norman, OK 73072 | Oil & Gas Operator | Oct 2025 |
| 4597 | Caddo Gas Processing L.L.C. | | Oil Operator | Aug 2012 |
| 4598 | Caddo Management, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Jan 2025 |
| 4599 | Caddo Oil & Gas Inc | Oklahoma City, OK 73157 | Oil & Gas Operator | Jan 1997 |
| 4600 | Caddo Oil & Gas Co., Inc. | | Oil Operator | Jul 1990 |