| 1 | B J Oil Company | Corsicana, TX 75109 | Oil & Gas Operator | Jun 2025 |
| 2 | Baldes Henry | Riverton, WY 82501 | Oil Operator | Dec 1998 |
| 3 | Balidor Oil & Gas LLC | Houston, TX 77070 | Oil & Gas Operator | Oct 2021 |
| 4 | Ballard Petroleum Holdings LLC | Billings, MT 59104 | Oil & Gas Operator | Apr 2025 |
| 5 | Balsam R C | | Oil & Gas Operator | Apr 1991 |
| 6 | Bandera Energy Company | | Oil & Gas Operator | Mar 1986 |
| 7 | Banding M R Inc | Gillette, WY 82717 | Oil & Gas Operator | Apr 2025 |
| 8 | Baney Well Service Inc | Denver, CO 80237 | Oil Operator | Jun 2016 |
| 9 | Banks And Conrad | | Oil Operator | Sep 1987 |
| 10 | Banks Operating Company | | Oil & Gas Operator | Jul 1989 |
| 11 | Bannon Energy Inc | Houston, TX 77068 | Oil & Gas Operator | Jun 1998 |
| 12 | Banta And Haigh | Aurora, CO 80014 | Oil & Gas Operator | Feb 1998 |
| 13 | Barbe D F | Recluse, WY 82725 | Oil & Gas Operator | Dec 2000 |
| 14 | Barn Owls LLC | | Oil & Gas Operator | Apr 2025 |
| 15 | Barrel Springs Development Corp | Denver, CO 80202 | Oil & Gas Operator | Oct 1986 |
| 16 | Barrett Patrick | | Oil & Gas Operator | Apr 1988 |
| 17 | Basf Corporation | Houston, TX 77027 | Oil & Gas Operator | Nov 1992 |
| 18 | Basin Oil & Gas Operating LLC | Fort Worth, TX 76107 | Oil & Gas Operator | Jun 2025 |
| 19 | Basin Resources Corporation | Fair Oaks Ranch, TX 78015 | Oil Operator | May 2013 |
| 20 | Bass Enterprises Production Co | Fort Worth, TX 76102 | Oil & Gas Operator | Dec 2006 |
| 21 | Bass Petroleum Inc | Austin, TX 78716 | Oil & Gas Operator | Jun 2025 |
| 22 | Bataa Oil Inc | Arvada, CO 80005 | Oil & Gas Operator | Apr 2025 |
| 23 | Bates Creek Oil | | Oil Operator | Dec 1986 |
| 24 | Bayless Robert L Producer | Denver, CO 80293 | Oil & Gas Operator | Sep 2003 |
| 25 | Bayswater Exploration & Production LLC | Denver, CO 80202 | Oil & Gas Operator | Mar 2025 |
| 26 | Baytex Energy USA LLC | Denver, CO 80202 | Oil & Gas Operator | Nov 2014 |
| 27 | Bear Oil And Gas Inc | Las Vegas, NV 89107 | Oil & Gas Operator | Jul 2016 |
| 28 | Bearcat Energy LLC (Colorado) | Denver, CO 80202 | Oil & Gas Operator | May 2022 |
| 29 | Bearcat Petroleum Inc | | Oil Operator | Dec 1991 |
| 30 | Beard Oil Company | Oklahoma City, OK 73102 | Oil & Gas Operator | Aug 2013 |
| 31 | Beartooth Oil & Gas Company | Billings, MT 59103 | Oil & Gas Operator | Apr 2025 |
| 32 | Belco Energy Corp. | Dallas, TX 75231 | Oil & Gas Operator | Mar 2015 |
| 33 | Belden & Blake Corporation | North Canton, OH 44720-0500-0500 | Oil & Gas Operator | Dec 2016 |
| 34 | Bell Resources Inc | Billings, MT 59104 | Oil & Gas Operator | Jun 2016 |
| 35 | Bellevue Resources Inc | Lakewood, CO 80235 | Oil & Gas Operator | Feb 2009 |
| 36 | Benchmark Energy LLC | Pratt, KS 67124 | Oil & Gas Operator | Sep 2023 |
| 37 | Bennett Petroleum Corporation | Denver, CO 80203 | Oil Operator | Jun 1985 |
| 38 | Benson-Montin-Greer DRLG Corp | Farmington, NM 87402 | Oil & Gas Operator | Apr 2025 |
| 39 | Berco Resources LLC | Denver, CO 80206 | Oil & Gas Operator | Sep 2009 |
| 40 | Beren Corporation | Wichita, KS 67206 | Oil & Gas Operator | Jun 2025 |
| 41 | Berenergy Corporation | Denver, CO 80217 | Oil & Gas Operator | Apr 2025 |
| 42 | Berry Petroleum Company | Denver, CO 80202 | Oil & Gas Operator | Feb 2014 |
| 43 | Beta Oil Company Inc | Oklahoma City, OK 73157-2958 | Oil & Gas Operator | Dec 2022 |
| 44 | Betop Inc | Ojai, CA 83203 | Oil & Gas Operator | Dec 1996 |
| 45 | BHB Oil Partners LLC | Powell, WY 82435 | Oil Operator | Apr 2025 |
| 46 | BHP Petroleum (USA) Inc | | Oil & Gas Operator | Mar 1993 |
| 47 | BHP Petroleum Company Inc | Houston, TX 77057 | Oil & Gas Operator | Jun 2016 |
| 48 | Big Basin Petroleum LLC | Gillette, WY 82717 | Oil & Gas Operator | Oct 2008 |
| 49 | Big Chief Exploration | Palisades, CO 81526 | Oil & Gas Operator | Oct 1993 |
| 50 | Big Muddy Operating LLC | Casper, WY 82602 | Oil Operator | Apr 2025 |
| 51 | Big Piney Oil & Gas Company | Dallas, TX 75206 | Oil & Gas Operator | Sep 1992 |
| 52 | Big Wells Energy Corp | Katy, TX 77494 | Oil & Gas Operator | Sep 2019 |
| 53 | Bill Barrett Corporation | Denver, CO 80202 | Oil & Gas Operator | Dec 2017 |
| 54 | Bing Harold C | Newcastle, WY 82701 | Oil Operator | Jun 1992 |
| 55 | Bird Oil Corporation | | Oil & Gas Operator | Jul 1992 |
| 56 | Bison IV Operating LLC | | Oil & Gas Operator | Apr 2025 |
| 57 | Bison Operating LLC | | Oil & Gas Operator | Apr 2025 |
| 58 | Bitterroot Energy Partners LLC | | Oil & Gas Operator | Apr 2025 |
| 59 | Black Bank LLC | Billings, MT 59103 | Oil Operator | Mar 2025 |
| 60 | Black Bear Oil Corporation | Las Vegas, NV 89128 | Oil & Gas Operator | Mar 2025 |
| 61 | Black Coal Resources Company | Fort Washakie, WY 82514 | Oil & Gas Operator | Dec 1991 |
| 62 | Black Diamond Energy Inc | Pittsburgh, PA 15237 | Gas Operator | May 2016 |
| 63 | Black Diamond Energy Of Delaware Inc | Buffalo, WY 82834 | Oil & Gas Operator | May 2025 |
| 64 | Black Gold Services Inc | Casper, WY 82644 | Oil & Gas Operator | Mar 2025 |
| 65 | Black Hawk Resources Corporation | Denver, CO 80202 | Oil Operator | Mar 1986 |
| 66 | Black Hills Exploration & Production Inc | Newcastle, WY 82701 | Oil & Gas Operator | May 2018 |
| 67 | Black Hills Wyoming Gas LLC | Rapid City, SD 57709 | Gas Operator | Apr 2025 |
| 68 | Black Jack Oil Co Inc | Holliday, TX 76366 | Oil & Gas Operator | Feb 2025 |
| 69 | Black Thunder Oil LLC | Gillette, WY 82717 | Oil & Gas Operator | Apr 2025 |
| 70 | Blackjack Oil, Inc. | Las Vegas, NV 89128 | Oil & Gas Operator | Nov 2019 |
| 71 | Blackstone Operating Inc | Red Lodge, MT 59068 | Gas Operator | Nov 2009 |
| 72 | Blake Production LLC | Gillette, WY 82717 | Oil & Gas Operator | Mar 2025 |
| 73 | Blue Spruce Operating LLC | Pinedale, WY 82941 | Oil & Gas Operator | Apr 2025 |
| 74 | Blue Tip Energy Wyoming Inc | Houston, TX 77284 | Oil Operator | Jun 2016 |
| 75 | Bluebonnet Energy Corporation | Englewood, CO 80112 | Oil & Gas Operator | Sep 2015 |
| 76 | Boelens Well Service LLC | Thermopolis, WY 82443 | Oil Operator | Dec 1999 |
| 77 | Boggy Creek Production | Newcastle, WY 82701 | Oil & Gas Operator | Apr 2012 |
| 78 | Borchert R V | Sidney, NE 69162 | Oil Operator | Apr 2009 |
| 79 | Bowden Energy Company Inc | Gillette, WY 82716 | Oil & Gas Operator | Mar 2025 |
| 80 | Bower Properties LLC | Worland, WY 82401 | Oil & Gas Operator | Aug 2005 |
| 81 | Bowers Oil & Gas, Inc. | Grand Junction, CO 81505-1097 | Oil & Gas Operator | Nov 2022 |
| 82 | Box H Resources | Cody, WY 82414 | Oil & Gas Operator | Dec 2007 |
| 83 | BP America Production Company | Denver, CO 80202 | Oil & Gas Operator | Feb 2025 |
| 84 | BP Exploration Inc | | Oil & Gas Operator | May 1993 |
| 85 | BP Production Company LLC | Evergreen, CO 80439 | Oil Operator | Jul 2001 |
| 86 | Braden Oil | | Oil & Gas Operator | Mar 2007 |
| 87 | Braden-Deem Inc | Wichita, KS 67226 | Oil & Gas Operator | Jan 2025 |
| 88 | Bradford Oil Company | Denver, CO 80249 | Oil & Gas Operator | Apr 2025 |
| 89 | Bradley Jr Jack C | Casper, WY 82601 | Oil & Gas Operator | Apr 2009 |
| 90 | Bradley SR Jack C | Newcastle, WY 82701 | Oil Operator | Jun 2010 |
| 91 | Brannon Oil & Gas Inc | Fort Worth, TX 76102 | Oil & Gas Operator | Feb 2013 |
| 92 | Breck Operating Corp. | Breckenridge, TX 76424 | Oil & Gas Operator | Feb 2025 |
| 93 | Brehm Investment Group Inc | | Oil Operator | Jul 1991 |
| 94 | Brehm Oil | MT. Vernon, IL 62864 | Oil Operator | Jan 1986 |
| 95 | Breitburn Energy Company LLC | Lakewood, CO 80227 | Oil Operator | Aug 2011 |
| 96 | Breitburn Operating LP | Houston, TX 77002 | Oil & Gas Operator | Jun 2025 |
| 97 | Brent Exploration | | Oil & Gas Operator | Dec 1993 |
| 98 | Bridger Petroleum Corp | | Oil & Gas Operator | Oct 1999 |
| 99 | Bridwell Oil Company | Wichita Falls, TX 76307 | Oil & Gas Operator | Jun 2025 |
| 100 | Brigham Oil & Gas, L.P. | Austin, TX 78730 | Oil & Gas Operator | Oct 2015 |