| 4501 | C & W Operating LLC | Tulsa, OK 74145-7627 | Oil Operator | May 2020 |
| 4502 | C & Y Casing Pulling Company | Duncan, OK 73533 | Oil & Gas Operator | Nov 2025 |
| 4503 | C A P Operating | | Oil Operator | Sep 1992 |
| 4504 | C And D Explorations LLC | | Oil Operator | Dec 2025 |
| 4505 | C And M Oil Inc | Kimball, NE 69145 | Oil & Gas Operator | Dec 2024 |
| 4506 | C And S Oil & Gas | San Antonio, TX 78217 | Oil & Gas Operator | Feb 1998 |
| 4507 | C Bar K Enterprises Inc | Oklahoma City, OK 73154-1828 | Oil & Gas Operator | Dec 2022 |
| 4508 | C Bar Petroleum Company | Lubbock, TX 79413 | Oil & Gas Operator | May 2018 |
| 4509 | C C & S Oil Oper | | Oil Operator | Apr 1983 |
| 4510 | C C Co | Holladay, UT 84124 | Oil & Gas Operator | Jan 2020 |
| 4511 | C D Oil | Wellsville, KS 66092 | Oil Operator | Aug 1998 |
| 4512 | C D Operating Company Inc | Oklahoma City, OK 73116 | Oil & Gas Operator | Apr 2015 |
| 4513 | C E D LC | Enid, OK 73702-0326 | Oil & Gas Operator | Oct 2021 |
| 4514 | C E Energy LLC | Katy, TX 77449 | Oil Operator | Feb 2026 |
| 4515 | C E Harmon Oil Inc | Tulsa, OK 74136-6559 | Oil & Gas Operator | Nov 2025 |
| 4516 | C E L Inc | Bartlesville, OK 74006 | Oil & Gas Operator | Jan 2020 |
| 4517 | C E Larue & B M Muncy Jr | Artesia, NM 882111370 | Oil & Gas Operator | Jun 2006 |
| 4518 | C E Long | Midland, TX 79702 | Oil & Gas Operator | Apr 1994 |
| 4519 | C E Staples | Dallas, TX 75205 | Oil & Gas Operator | Jul 1995 |
| 4520 | C F & L Producing Co | | Oil & Gas Operator | Sep 2000 |
| 4521 | C F M Oil Co Dba Louis And Judy Fulton | Artesia, NM 88210 | Oil & Gas Operator | May 2011 |
| 4522 | C F Oil - Frazie | | Oil Operator | Dec 1994 |
| 4523 | C G Davis, Et Al | | Oil & Gas Operator | Mar 1986 |
| 4524 | C G G Oil Co | | Oil & Gas Operator | Dec 2006 |
| 4525 | C G O Inc | Wheeling, WV 26003 | Oil & Gas Operator | Dec 2024 |
| 4526 | C G Oil, Inc. | Victoria, KS 67671 | Oil Operator | Sep 2025 |
| 4527 | C H E Company Inc | Shawnee, OK 74801 | Oil Operator | Feb 2012 |
| 4528 | C H K Oil, LLC | Stephens, AR 71764 | Oil Operator | Jan 2025 |
| 4529 | C K Oil Company | Great Bend, KS 67530 | Oil & Gas Operator | Sep 2025 |
| 4530 | C L & S Oil Company Inc | Perry, OK 73077-0841 | Oil & Gas Operator | Jan 2018 |
| 4531 | C L Conner | Humble, TX 77338 | Oil & Gas Operator | Oct 2025 |
| 4532 | C M F Oil LLC | | Oil Operator | Dec 2024 |
| 4533 | C M S Gas Transmission Co | | Oil & Gas Operator | Dec 2020 |
| 4534 | C M S Oil And Gas Co And Miller Brothers | | Oil & Gas Operator | Apr 1992 |
| 4535 | C M T Petroleum | | Oil Operator | Jul 1995 |
| 4536 | C M X Incorporat | | Oil & Gas Operator | Dec 1996 |
| 4537 | C N B Enterprises | Yates Center, KS 66783 | Oil & Gas Operator | Jan 2009 |
| 4538 | C N Operating Co | Drumright, OK 74030 | Oil & Gas Operator | Nov 1998 |
| 4539 | C O Fulton | Artesia, NM 88211 | Oil & Gas Operator | Sep 2022 |
| 4540 | C O G Company | Bangs, TX 76823 | Oil & Gas Operator | Feb 2026 |
| 4541 | C Oil Co. | New Braunfels, TX 78132 | Oil & Gas Operator | Feb 2017 |
| 4542 | C R A C O Incorp | | Oil Operator | May 1988 |
| 4543 | C R I Inc | Midland, TX 79702 | Oil & Gas Operator | Nov 1993 |
| 4544 | C Rose Oil Co. | Midland, TX 79708 | Oil & Gas Operator | Oct 2025 |
| 4545 | C S J, Inc. | Austin, TX 78716 | Oil & Gas Operator | Feb 2026 |
| 4546 | C T R Resources Inc | Alliance, OH 44601 | Oil & Gas Operator | Dec 2013 |
| 4547 | C W Oil Producer | | Oil Operator | Oct 1998 |
| 4548 | C W Riggs Inc | St. Marys, WV 26170 | Oil & Gas Operator | Dec 1999 |
| 4549 | C W Trainer | Midland, TX 79702 | Oil & Gas Operator | Nov 2009 |
| 4550 | C&C II | Pleasanton, TX 78064 | Oil & Gas Operator | Mar 1998 |
| 4551 | C&D Management Company Dba Freedom Ventures | Las Vegas, NV 89149 | Oil & Gas Operator | Feb 2019 |
| 4552 | C&M Operating Company, LLC | | Oil & Gas Operator | Apr 2011 |
| 4553 | C&P Resources Operating Co,LLC | Houston, TX 77056 | Oil & Gas Operator | Feb 2026 |
| 4554 | C-D Oil Company, Inc. | Cameron, TX 76520 | Oil Operator | Feb 2026 |
| 4555 | C-V Oil Company | Memphis, TN 38103 | Oil Operator | Jun 1998 |
| 4556 | C-Water Disposal Inc | Oklahoma City, OK 73116-7326 | Oil Operator | Dec 2014 |
| 4557 | C. A. Cardneaux, Inc. | | Oil & Gas Operator | Apr 1990 |
| 4558 | C. C. Killingsworth Opr. | | Oil Operator | Dec 1999 |
| 4559 | C. Case Company | | Oil & Gas Operator | Oct 2025 |
| 4560 | C. D. Oil, Inc. | Wellsville, KS 66092 | Oil Operator | Dec 2009 |
| 4561 | C. D. Pierce | | Oil Operator | Mar 1991 |
| 4562 | C. E. Allen Co. Inc. | | Oil & Gas Operator | Nov 2025 |
| 4563 | C. E. Braly | | Oil & Gas Operator | Dec 1991 |
| 4564 | C. F. Oil, A General Partnership | Lake Lotawana, MO 64086 | Oil Operator | Sep 2025 |
| 4565 | C. F. Sudduth | | Oil & Gas Operator | Dec 1988 |
| 4566 | C. H. C. Gerard | | Oil & Gas Operator | Jan 2025 |
| 4567 | C. H. Cuatro | | Gas Operator | Sep 1996 |
| 4568 | C. H. Todd, Inc. | Wichita, KS 67212 | Oil & Gas Operator | Dec 2019 |
| 4569 | C. I. McKown & Son, Inc. | Newton, WV 25266-0711 | Oil & Gas Operator | Dec 2021 |
| 4570 | C. J. Broome Oil Company | | Oil & Gas Operator | Jan 2020 |
| 4571 | C. J. Filson, LLC | Protection, KS 67127 | Gas Operator | Aug 2014 |
| 4572 | C. J. Services | | Oil & Gas Operator | Sep 2016 |
| 4573 | C. L. Brown, III | | Oil Operator | Dec 1991 |
| 4574 | C. L. Brown, Inc. | | Oil Operator | Dec 1999 |
| 4575 | C. L. Morris | | Oil Operator | Feb 2004 |
| 4576 | C. L. Morris, Inc. | | Oil & Gas Operator | Feb 2004 |
| 4577 | C. M. Frizzell | | Oil & Gas Operator | Mar 2014 |
| 4578 | C. M. Oil Corporation | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Mar 2016 |
| 4579 | C. M. Roberson | | Oil Operator | Jun 1984 |
| 4580 | C. O. Oil And Gas, LLC | Pampa, TX 79066 | Oil & Gas Operator | Feb 2026 |
| 4581 | C. Smith & Associates, Inc. | | Oil Operator | Aug 1991 |
| 4582 | C. T. & Ted Paul | | Oil Operator | Mar 2019 |
| 4583 | C. V. Radke | | Oil Operator | Jan 1993 |
| 4584 | C. W. Brumley | | Oil & Gas Operator | Jun 2006 |
| 4585 | C. W. Resources, Inc. | Longview, TX 75604 | Oil & Gas Operator | Oct 2025 |
| 4586 | C. Wayland Brooks | | Oil & Gas Operator | Dec 1987 |
| 4587 | C.B.C. Producing Co. | | Oil & Gas Operator | Jul 1989 |
| 4588 | C.C.O. & G. Company Inc. | Austin, TX 78765 | Oil & Gas Operator | Sep 1995 |
| 4589 | C.F. Braun & Company | | Oil & Gas Operator | Dec 1986 |
| 4590 | C.F.D. Inc. | | Oil & Gas Operator | Nov 1988 |
| 4591 | C.F.O., Inc. | Liberty, TX 77575 | Oil Operator | Feb 2026 |
| 4592 | C.J. Oil Company | Iowa Park, TX 76367 | Oil Operator | Jan 2025 |
| 4593 | C.O.W. Operating Company | Graham, TX 76450 | Oil Operator | Feb 2026 |
| 4594 | C.P.I. | | Oil & Gas Operator | Oct 2007 |
| 4595 | C.S.V. Oil Exploration Co | West Jordan, UT 84088 | Gas Operator | Nov 2025 |
| 4596 | C.T.R. Oil, Inc. | | Oil & Gas Operator | Jan 2025 |
| 4597 | C.W. Pickering, Inc. | Victoria, TX 77904 | Gas Operator | Sep 2022 |
| 4598 | C.W.F.K., Inc. | | Gas Operator | Dec 1986 |
| 4599 | C12 Energy: North Dakota LLC | | Oil Operator | Apr 2017 |
| 4600 | C12 Kansas Oil, LLC | Denver, CO 80202 | Oil Operator | Dec 2009 |