| 1 | 1876 Resources LLC | Highlands Ranch, CO 80129 | Oil & Gas Operator | Sep 2024 |
| 2 | Abraxas Petroleum Corporation | San Antonio, TX 78259 | Oil & Gas Operator | Nov 2024 |
| 3 | Advanced Recovery Services Co | Denver, CO 80265 | Oil & Gas Operator | Apr 2007 |
| 4 | Aexco Petroleum Inc | Denver, CO 80202 | Oil & Gas Operator | Sep 2024 |
| 5 | Allen And Crouch | Casper, WY 82602 | Oil & Gas Operator | Mar 2020 |
| 6 | American Eagle Oil | Casper, WY 82605 | Oil & Gas Operator | Dec 2012 |
| 7 | American Exploration Company | Houston, TX 77010 | Oil & Gas Operator | Jan 2000 |
| 8 | Anadarko E&P Onshore LLC | Houston, TX 77046 | Oil & Gas Operator | Nov 2024 |
| 9 | Anadarko Petroleum Corporation | Houston, TX 77251 | Oil & Gas Operator | Sep 2024 |
| 10 | Anchor Bay Corporation | Denver, CO 80202 | Oil & Gas Operator | Jun 2007 |
| 11 | Anderson Management Company | Gillette, WY 82716 | Oil & Gas Operator | May 2016 |
| 12 | Anderson Oil Company | Burkburnett, TX 76354 | Oil & Gas Operator | Dec 2015 |
| 13 | Anr Production Company | Houston, TX 77046 | Oil & Gas Operator | Aug 2017 |
| 14 | Anschutz Corporation, The | Denver, CO 80202 | Oil & Gas Operator | Sep 2016 |
| 15 | Anschutz Exploration Corporation | Denver, CO 80202 | Oil & Gas Operator | Nov 2024 |
| 16 | Anschutz Oil Company LLC | Denver, CO 80202 | Oil & Gas Operator | Sep 2020 |
| 17 | Ant Hills Production | Lusk, WY 82225 | Oil & Gas Operator | Aug 2024 |
| 18 | Antelope Energy Company LLC | Denver, CO 80202 | Oil & Gas Operator | Sep 2024 |
| 19 | Apache Corporation | Houston, TX 77042 | Oil & Gas Operator | Nov 2024 |
| 20 | Arjay Oil Company | Salt Lake City, UT 84110 | Oil & Gas Operator | May 2000 |
| 21 | Ashland Exploration | | Oil & Gas Operator | May 1979 |
| 22 | Atlantic Oil Corporation | Denver, CO 80206 | Oil & Gas Operator | Dec 1982 |
| 23 | Atlantic Richfield Company | Plano, TX 75074 | Oil & Gas Operator | Dec 2016 |
| 24 | Avalon Energy Corporation | | Oil & Gas Operator | Jul 1990 |
| 25 | Aztec Gas And Oil Corporation | Elephant Butte, NM 87935-0370 | Oil & Gas Operator | Mar 2005 |
| 26 | Balidor Oil & Gas LLC | Houston, TX 77070 | Oil & Gas Operator | Oct 2021 |
| 27 | Ballard Petroleum Holdings LLC | Billings, MT 59104 | Oil & Gas Operator | Sep 2024 |
| 28 | Banks Operating Company | | Oil & Gas Operator | Jul 1989 |
| 29 | Barn Owls LLC | | Oil & Gas Operator | Sep 2024 |
| 30 | Barrett Patrick | | Oil & Gas Operator | Apr 1988 |
| 31 | Bass Enterprises Production Co | Fort Worth, TX 76102 | Oil & Gas Operator | Dec 2006 |
| 32 | Bass Petroleum Inc | Austin, TX 78716 | Oil & Gas Operator | Nov 2024 |
| 33 | Bearcat Energy LLC (Colorado) | Denver, CO 80202 | Oil & Gas Operator | May 2022 |
| 34 | Beard Oil Company | Oklahoma City, OK 73102 | Oil & Gas Operator | Aug 2013 |
| 35 | Berenergy Corporation | Denver, CO 80217 | Oil & Gas Operator | Sep 2024 |
| 36 | Big Chief Exploration | Palisades, CO 81526 | Oil & Gas Operator | Oct 1993 |
| 37 | Big Muddy Operating LLC | Casper, WY 82602 | Oil Operator | Sep 2024 |
| 38 | Bill Barrett Corporation | Denver, CO 80202 | Oil & Gas Operator | Dec 2017 |
| 39 | Black Bear Oil Corporation | Las Vegas, NV 89128 | Oil & Gas Operator | Sep 2024 |
| 40 | Black Diamond Energy Inc | Pittsburgh, PA 15237 | Gas Operator | May 2016 |
| 41 | Black Gold Services Inc | Casper, WY 82644 | Oil & Gas Operator | Jul 2024 |
| 42 | Black Hills Exploration & Production Inc | Newcastle, WY 82701 | Oil & Gas Operator | May 2018 |
| 43 | Blackjack Oil, Inc. | Las Vegas, NV 89128 | Oil & Gas Operator | Nov 2019 |
| 44 | Blue Tip Energy Wyoming Inc | Houston, TX 77284 | Oil Operator | Jun 2016 |
| 45 | Bowers Oil & Gas, Inc. | Grand Junction, CO 81505-1097 | Oil & Gas Operator | Nov 2022 |
| 46 | BP America Production Company | Denver, CO 80202 | Oil & Gas Operator | Sep 2024 |
| 47 | Bright Rock Energy LLC | Denver, CO 80202 | Oil & Gas Operator | Sep 2024 |
| 48 | Bronco Oil & Gas Co | Casper, WY 82602 | Oil & Gas Operator | Oct 1987 |
| 49 | Brown Doug & Larita | Newcastle, WY 82701 | Oil & Gas Operator | May 2024 |
| 50 | Brown Tom Inc | Dallas, TX 75240 | Oil & Gas Operator | Mar 2015 |
| 51 | Burlington Resources Oil & Gas Company L | Gillette, WY 82718 | Oil & Gas Operator | Jan 2022 |
| 52 | Burnett Oil Co Inc | Fort Worth, TX 76102 | Oil & Gas Operator | Nov 2024 |
| 53 | Bwab Incorporated | Denver, CO 80202 | Oil & Gas Operator | Aug 1996 |
| 54 | Capitol Oil & Gas Corporation | Centennial, WY 82055 | Oil Operator | Feb 2006 |
| 55 | Carol-Holly Oil Corporation | Denver, CO 80237 | Oil & Gas Operator | Sep 2024 |
| 56 | Celsius Energy Company | Denver, CO 80202-1558 | Oil & Gas Operator | Mar 2000 |
| 57 | Central Resources Inc | Denver, CO 80203 | Oil & Gas Operator | Dec 2019 |
| 58 | Central Wyoming Resources LTD | Glenrock, WY 82637 | Oil Operator | Jul 2021 |
| 59 | Century Production Inc | | Oil & Gas Operator | Dec 1986 |
| 60 | Chaco Energy Company | Denver, CO 80201 | Oil & Gas Operator | Sep 2024 |
| 61 | Chambers Jerry | Denver, CO 80237 | Oil & Gas Operator | Dec 1993 |
| 62 | Chaparral Energy, L.L.C. | Oklahoma City, OK 73142 | Oil & Gas Operator | Nov 2024 |
| 63 | Chaparral Resources Inc | Denver, CO 80293 | Oil & Gas Operator | Jan 1996 |
| 64 | Chapman Exploration Inc | Tulsa, OK 74136 | Oil & Gas Operator | Aug 2013 |
| 65 | Charger Resources, LLC | Hurst, TX 76054 | Oil & Gas Operator | Aug 2015 |
| 66 | Chemily Management Company | Cypress, TX 77429 | Oil & Gas Operator | Apr 2023 |
| 67 | Chesapeake Operating, LLC | Oklahoma City, OK 73154 | Oil & Gas Operator | Nov 2024 |
| 68 | Chevron USA Inc | Midland, TX 79706 | Oil & Gas Operator | Nov 2024 |
| 69 | Chipcore LLC | Casper, WY 82601 | Oil & Gas Operator | Sep 2024 |
| 70 | Chippewa Oil & Gas Inc | Douglas, WY 82633 | Oil & Gas Operator | Jan 1985 |
| 71 | Chriscor Oil & Gas | Plana, TX 75075 | Oil & Gas Operator | Jul 1987 |
| 72 | Citation Oil & Gas Corp. | Houston, TX 77269 | Oil & Gas Operator | Nov 2024 |
| 73 | Coastal Oil & Gas Corporation | Houston, TX 77252 | Oil & Gas Operator | Dec 2009 |
| 74 | Cobra Oil & Gas Corporation | Wichita Falls, TX 76307 | Oil & Gas Operator | Nov 2024 |
| 75 | Coleman Oil & Gas Inc | Farmington, NM 87499 | Oil & Gas Operator | Jan 2023 |
| 76 | Colorado Oil & Gas Corporation | | Oil & Gas Operator | May 2003 |
| 77 | Combined Oil & Gas | Denver, CO 80202 | Oil & Gas Operator | Feb 1990 |
| 78 | Comet Energy Services LLC | Traverse City, MI 49686 | Oil & Gas Operator | Oct 2011 |
| 79 | Common Energy Inc | Douglas, WY 82633 | Oil & Gas Operator | Aug 1995 |
| 80 | Conoco Inc. | Houston, TX 77252 | Oil & Gas Operator | Mar 2015 |
| 81 | Conquest Exploration | Houston, TX 77068 | Oil & Gas Operator | May 1991 |
| 82 | Contango Resources LLC | Houston, TX 77002 | Oil & Gas Operator | Nov 2024 |
| 83 | Continental Industries LC | Casper, WY 82602 | Oil & Gas Operator | Feb 2008 |
| 84 | Continental Production Co LLC | Greenwood VIllage, CO 80155 | Oil & Gas Operator | Aug 2012 |
| 85 | Continental Resources, Inc. | Oklahoma City, OK 73126 | Oil & Gas Operator | Nov 2024 |
| 86 | Convest Energy Corporation | Houston, TX 77057 | Oil & Gas Operator | Sep 2014 |
| 87 | Cook D L | Holliday, TX 76366 | Oil & Gas Operator | Dec 2008 |
| 88 | Coquina Oil Corporation | Houston, TX 77227 | Oil & Gas Operator | Mar 2015 |
| 89 | Corrida Oil Inc | Denver, CO 80217 | Oil & Gas Operator | Jun 1990 |
| 90 | Cotton Petroleum Corporation | Tulsa, OK 74102 | Oil & Gas Operator | Jan 2005 |
| 91 | Crawley Petroleum Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | Nov 2024 |
| 92 | Creek Oil Company | Colorado Springs, CO 80906 | Oil & Gas Operator | Aug 2001 |
| 93 | D K Cook Heirs LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2011 |
| 94 | Dahill Murray P | Casper, WY 82601 | Oil & Gas Operator | Jun 2007 |
| 95 | Davis Exploration | | Oil Operator | Dec 2007 |
| 96 | Davis Oil Company | Pawhuska, OK 74056 | Oil & Gas Operator | Jun 2018 |
| 97 | DCD Inc | Gillette, WY 82716 | Oil & Gas Operator | Aug 2003 |
| 98 | Degaugh Well Service Inc | | Oil Operator | Jul 1989 |
| 99 | Dekalb Energy Company | Oklahoma City, OK 73134 | Oil & Gas Operator | Oct 1996 |
| 100 | Devon Energy Operating Corp | Oklahoma City, OK 73102 | Oil & Gas Operator | Apr 2013 |