| 4501 | C. Smith & Associates, Inc. | | Oil Operator | Aug 1991 |
| 4502 | C. T. & Ted Paul | | Oil Operator | Mar 2019 |
| 4503 | C. V. Radke | | Oil Operator | Jan 1993 |
| 4504 | C. W. Brumley | | Oil & Gas Operator | Jun 2006 |
| 4505 | C. W. Resources, Inc. | Longview, TX 75604 | Oil & Gas Operator | Oct 2025 |
| 4506 | C. Wayland Brooks | | Oil & Gas Operator | Dec 1987 |
| 4507 | C.B.C. Producing Co. | | Oil & Gas Operator | Jul 1989 |
| 4508 | C.C.O. & G. Company Inc. | Austin, TX 78765 | Oil & Gas Operator | Sep 1995 |
| 4509 | C.D. Operating Company, Inc. | Oklahoma City, OK 73116 | Oil & Gas Operator | Apr 2015 |
| 4510 | C.F. Braun & Company | | Oil & Gas Operator | Dec 1986 |
| 4511 | C.F.D. Inc. | | Oil & Gas Operator | Nov 1988 |
| 4512 | C.F.O., Inc. | Liberty, TX 77575 | Oil Operator | Oct 2025 |
| 4513 | C.J. Oil Company | Iowa Park, TX 76367 | Oil Operator | Jan 2025 |
| 4514 | C.O.W. Operating Company | Graham, TX 76450 | Oil Operator | Oct 2025 |
| 4515 | C.P.I. | | Oil & Gas Operator | Oct 2007 |
| 4516 | C.S.V. Oil Exploration Co | West Jordan, UT 84088 | Gas Operator | Jul 2025 |
| 4517 | C.T.R. Oil, Inc. | | Oil & Gas Operator | Jan 2025 |
| 4518 | C.W. Pickering, Inc. | Victoria, TX 77904 | Gas Operator | Sep 2022 |
| 4519 | C.W.F.K., Inc. | | Gas Operator | Dec 1986 |
| 4520 | C12 Energy: North Dakota LLC | | Oil Operator | Apr 2017 |
| 4521 | C12 Kansas Oil, LLC | Denver, CO 80202 | Oil Operator | Dec 2009 |
| 4522 | C3oil, LLC | New Strawn, KS 66839 | Oil Operator | Jun 2025 |
| 4523 | C5 Energy LLC | Collinsville, OK 74021 | Oil & Gas Operator | Dec 2019 |
| 4524 | C6 Operating, L.L.C. | Keatchie, LA 71046 | Oil & Gas Operator | Oct 2025 |
| 4525 | Caac 100 LLC | | Oil & Gas Operator | Jul 2025 |
| 4526 | Cab Resources, LLC | Odessa, TX 79762 | Oil Operator | Oct 2025 |
| 4527 | Caba, LLC | | Oil Operator | Jan 2025 |
| 4528 | Cabal Energy Corporation | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 4529 | Caballero Operations LLC | | Oil & Gas Operator | Aug 2025 |
| 4530 | Cabana Oil Corp. | Abilene, TX 79608 | Oil & Gas Operator | Feb 2006 |
| 4531 | Cabeza Oil And Gas, LLC | Austin, CO 81410 | Oil & Gas Operator | Mar 2022 |
| 4532 | Cable W S | Cleveland, OK 74020 | Oil Operator | Jan 2021 |
| 4533 | Cabot Exploration Corp | Houston, TX 77070 | Oil Operator | Jun 1999 |
| 4534 | Cabot Oil & Gas Corporation | Houston, TX 77024 | Oil & Gas Operator | Jun 2025 |
| 4535 | Cabot Oil & Gas Production Corp. | Houston, TX 77060 | Oil & Gas Operator | Jun 1996 |
| 4536 | Cabot Petroleum | | Oil & Gas Operator | Oct 1996 |
| 4537 | Cabot Petroleum Corporation | Englewood, CO 80111-2529 | Oil & Gas Operator | Dec 2004 |
| 4538 | Cactus Energy Company LLC | Hennessey, OK 73742 | Oil & Gas Operator | Jul 2025 |
| 4539 | Cactus Gas & Oil, Inc. | San Antonio, TX 78259 | Oil & Gas Operator | Oct 2025 |
| 4540 | Cactus Jack Operating Company | Carrizo SPGS, TX 78834 | Oil & Gas Operator | Aug 2003 |
| 4541 | Cactus Oil & Gas LLC | Seminole, OK 74868-2430 | Oil & Gas Operator | Mar 2018 |
| 4542 | Cactus Oil Company | Pampa, TX 79066 | Oil & Gas Operator | Aug 2000 |
| 4543 | Cactus Operating Company | Wichita Falls, TX 76301 | Oil & Gas Operator | Nov 2000 |
| 4544 | Cactus Operating Company, LLC | Lovington, NM 88260 | Oil & Gas Operator | Jul 2005 |
| 4545 | Cactus Petroleum Corporation | Houston, TX 77077 | Oil & Gas Operator | Oct 2025 |
| 4546 | Cad Energy Corporation | Creston, WV 26141 | Oil & Gas Operator | Dec 2021 |
| 4547 | Cada Operating, Inc. | Wichita Falls, TX 76307 | Oil & Gas Operator | Nov 2004 |
| 4548 | Caddeaux Gathering, LLC | | Oil Operator | Dec 2024 |
| 4549 | Caddell Well Service, Inc. | Prairie Lea, TX 78661 | Oil & Gas Operator | Oct 2025 |
| 4550 | Caddo Corporation | Austin, TX 78731 | Oil & Gas Operator | Oct 2025 |
| 4551 | Caddo Creek Corporation | Breckenridge, TX 76424 | Oil & Gas Operator | Dec 1994 |
| 4552 | Caddo Exploration, LLC | Norman, OK 73072 | Oil & Gas Operator | Jul 2025 |
| 4553 | Caddo Gas Processing L.L.C. | | Oil Operator | Aug 2012 |
| 4554 | Caddo Management, Inc | Shreveport, LA 71101 | Oil & Gas Operator | Jan 2025 |
| 4555 | Caddo Oil & Gas Inc | Oklahoma City, OK 73157 | Oil & Gas Operator | Jan 1997 |
| 4556 | Caddo Oil & Gas Co., Inc. | | Oil Operator | Jul 1990 |
| 4557 | Caddo Oil Co.,Inc. | | Oil & Gas Operator | Apr 1987 |
| 4558 | Caddo Operating Inc. | Marshall, TX 75671 | Oil & Gas Operator | Oct 2025 |
| 4559 | Caddo Parish Holdings LLC | | Oil & Gas Operator | Jul 2020 |
| 4560 | Caddo Petroleum Dev., Inc. | | Oil Operator | Aug 1986 |
| 4561 | Caddo Pine Island Corp. | | Oil & Gas Operator | Sep 1997 |
| 4562 | Caddo Pine Island Operating Co | | Oil & Gas Operator | Aug 1998 |
| 4563 | Caddo Resources Inc | | Oil & Gas Operator | Dec 1986 |
| 4564 | Caddo Western Development, Inc | | Oil & Gas Operator | Aug 1984 |
| 4565 | Caddo-Marchand LC | Dallas, TX 75251-2202 | Oil & Gas Operator | Oct 2016 |
| 4566 | Cadence Energy Partners, LLC | Blanchard, OK 73010 | Oil & Gas Operator | Jun 2010 |
| 4567 | Cadillac Operating Company, LLC | | Oil Operator | Jan 2025 |
| 4568 | Cady Myrle L | Sugar Grove, PA 16350-9803 | Oil & Gas Operator | Dec 2024 |
| 4569 | Caelus Natural Resources Alaska, LLC | | Oil & Gas Operator | Jul 2019 |
| 4570 | Caerus Kansas LLC | Denver, CO 80202 | Oil & Gas Operator | Jun 2025 |
| 4571 | Caerus Northern Rockies LLC | Denver, CO 80202 | Oil & Gas Operator | Mar 2021 |
| 4572 | Caerus Piceance LLC | | Oil & Gas Operator | Feb 2025 |
| 4573 | Caerus Southern Rockies LLC | Denver, CO 80202 | Gas Operator | Nov 2017 |
| 4574 | Caerus Uinta, LLC | Denver, CO 80202 | Oil & Gas Operator | Jul 2025 |
| 4575 | Caerus Washco LLC | Denver, CO 80202 | Oil & Gas Operator | Feb 2019 |
| 4576 | Caflisch, James E. | Clymer, NY 14724 | Gas Operator | Dec 2024 |
| 4577 | Cag Petroleum Corp. | Dallas, TX 75382 | Oil & Gas Operator | Oct 2025 |
| 4578 | Cago, Inc. | College Sta, TX 77845 | Oil & Gas Operator | Oct 2025 |
| 4579 | Cahoj, H. Drilling | McDonald, KS 67745 | Oil Operator | Jan 2000 |
| 4580 | Cain Glen | | Oil Operator | Dec 2016 |
| 4581 | Cain Randy A | Duncan, OK 73533 | Oil & Gas Operator | Jun 2025 |
| 4582 | Cain Richard | Comanche, OK 73529-1248 | Oil & Gas Operator | May 2020 |
| 4583 | Cain, Chas | Lexington, KY 40509 | Oil & Gas Operator | Dec 2023 |
| 4584 | Cain, Francis E. | Big Bend, WV 26136-0080 | Oil & Gas Operator | Dec 2021 |
| 4585 | Cain, Jim | Great Bend, KS 67530 | Oil Operator | Feb 2009 |
| 4586 | Cain, L. L. & White, Wayne R. | Lubbock, TX 79407 | Oil & Gas Operator | Apr 2005 |
| 4587 | Cain, Milton | Big Bend, WV 26136-0008 | Oil & Gas Operator | Dec 2021 |
| 4588 | Cain, Nicholas A & Darry R | | Oil Operator | Dec 2003 |
| 4589 | Caird Operating, LLC | Fort Worth, TX 76185 | Oil & Gas Operator | Oct 2025 |
| 4590 | Cairn Energy Partners, LLC | | Oil & Gas Operator | Feb 2023 |
| 4591 | Cajeza Energy | Drumright, OK 74030 | Oil & Gas Operator | May 2013 |
| 4592 | Cajun Minerals, Inc. | | Oil & Gas Operator | Mar 1997 |
| 4593 | Cajun Operating, Inc. | | Oil & Gas Operator | Jun 2011 |
| 4594 | Cal Ban Corp. | Olean, NY 14760 | Oil & Gas Operator | Dec 2023 |
| 4595 | Cal Continental Capital Inc. | | Oil Operator | Dec 2006 |
| 4596 | Cal Oil | | Oil Operator | Jul 1986 |
| 4597 | Cal Oil Company | Missouri City, TX 77459 | Oil Operator | May 2022 |
| 4598 | Cal-Mon Oil Company | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 4599 | Cal-T Oil Company, Incorporated | Borger, TX 79008 | Oil & Gas Operator | Feb 2008 |
| 4600 | Cal-Tex Exploration & Production Company LLC | San Antonio, TX 78228 | Oil & Gas Operator | Oct 2025 |