| 1 | Aberdeen Petroleum (USA) Inc. | Abilene, TX 79608 | Oil & Gas Operator | Sep 1994 |
| 2 | Abraxas Petroleum Corporation | San Antonio, TX 78259 | Oil & Gas Operator | Mar 2026 |
| 3 | Adams H D LLC | Moorcroft, WY 82721 | Oil & Gas Operator | Feb 2026 |
| 4 | Advanced Recovery Services Co | Denver, CO 80265 | Oil & Gas Operator | Apr 2007 |
| 5 | Aexco Petroleum Inc | Denver, CO 80202 | Oil & Gas Operator | Jan 2026 |
| 6 | Alpha Petrovision Us Inc | Canada, 00100 | Oil & Gas Operator | May 2013 |
| 7 | Am-West Petroleum Inc | Upton, WY 82730 | Oil & Gas Operator | Sep 2015 |
| 8 | Amax Oil & Gas Inc. | Fort Worth, TX 76107 | Oil & Gas Operator | Nov 2014 |
| 9 | American Eagle Oil | Casper, WY 82605 | Oil & Gas Operator | Dec 2012 |
| 10 | American Exploration Company | Houston, TX 77010 | Oil & Gas Operator | Jan 2000 |
| 11 | Ampolex Wy Inc | Gillette, WY 82716 | Oil & Gas Operator | Mar 1997 |
| 12 | Anchor Bay Corporation | Denver, CO 80202 | Oil & Gas Operator | Jun 2007 |
| 13 | Apache Corporation | Houston, TX 77042 | Oil & Gas Operator | Mar 2026 |
| 14 | Argent Energy (Us) Holdings Inc | Sugar Land, TX 77479 | Oil & Gas Operator | Sep 2021 |
| 15 | Atasca Resources, Inc. | Houston, TX 77219 | Oil & Gas Operator | Mar 2026 |
| 16 | Atlantic Richfield Company | Houston, TX 77079 | Oil & Gas Operator | Dec 2016 |
| 17 | Ballard Petroleum Holdings LLC | Billings, MT 59104 | Oil & Gas Operator | Jan 2026 |
| 18 | Banding M R Inc | Gillette, WY 82717 | Oil & Gas Operator | Jan 2026 |
| 19 | Barn Owls LLC | | Oil & Gas Operator | Jan 2026 |
| 20 | Bataa Oil Inc | Arvada, CO 80005 | Oil & Gas Operator | Jan 2026 |
| 21 | Beartooth Oil & Gas Company | Billings, MT 59103 | Oil & Gas Operator | Jan 2026 |
| 22 | Belden & Blake Corporation | North Canton, OH 44720 | Oil & Gas Operator | Dec 2016 |
| 23 | Beren Corporation | Wichita, KS 67206 | Oil & Gas Operator | Mar 2026 |
| 24 | Berenergy Corporation | Denver, CO 80217 | Oil & Gas Operator | Feb 2026 |
| 25 | Beta Oil Company Inc | Oklahoma City, OK 73157-2958 | Oil & Gas Operator | Nov 2025 |
| 26 | BHP Petroleum (USA) Inc | | Oil & Gas Operator | Mar 1993 |
| 27 | Big Basin Petroleum LLC | Gillette, WY 82717 | Oil & Gas Operator | Oct 2008 |
| 28 | Big Chief Exploration | Palisades, CO 81526 | Oil & Gas Operator | Oct 1993 |
| 29 | Black Bank LLC | Billings, MT 59103 | Oil Operator | Nov 2025 |
| 30 | Black Hills Exploration & Production Inc | Newcastle, WY 82701 | Oil & Gas Operator | Mar 2018 |
| 31 | Black Thunder Oil LLC | Gillette, WY 82717 | Oil & Gas Operator | Dec 2025 |
| 32 | Borchert R V | Sidney, NE 69162 | Oil Operator | Apr 2009 |
| 33 | Bowden Energy Company Inc | Gillette, WY 82716 | Oil & Gas Operator | Nov 2025 |
| 34 | BP America Production Company | Denver, CO 80202 | Oil & Gas Operator | Dec 2025 |
| 35 | Bradley SR Jack C | Newcastle, WY 82701 | Oil Operator | Jun 2010 |
| 36 | Breck Operating Corp. | Breckenridge, TX 76424 | Oil & Gas Operator | Dec 2025 |
| 37 | Burk Royalty Co., LTD. | Wichita Falls, TX 76308 | Oil & Gas Operator | Mar 2026 |
| 38 | Burlington Resources Oil & Gas Company L | Gillette, WY 82718 | Oil & Gas Operator | Jan 2022 |
| 39 | Burr Oil & Gas Inc | Farmington, NM 87499 | Oil & Gas Operator | Oct 2019 |
| 40 | BW Oil LLC | Hamel, MN 55340 | Oil Operator | Jun 2015 |
| 41 | Bwab Incorporated | Denver, CO 80202 | Oil & Gas Operator | Aug 1996 |
| 42 | BXP Operating, LLC | Houston, TX 77079 | Oil & Gas Operator | Mar 2026 |
| 43 | C & H Well Servicing Inc | Gillette, WY 82717 | Oil & Gas Operator | Jan 2026 |
| 44 | Cambria Oil Company | Casper, WY 82601 | Oil & Gas Operator | Dec 1996 |
| 45 | Cardinal Wyoming LLC | | Oil & Gas Operator | Jan 2026 |
| 46 | Chaparral Resources Inc | Denver, CO 80293 | Oil & Gas Operator | Jan 1996 |
| 47 | Charger Resources, LLC | Hurst, TX 76054 | Oil & Gas Operator | Aug 2015 |
| 48 | Chipcore LLC | Casper, WY 82601 | Oil & Gas Operator | Jan 2026 |
| 49 | CHS McPherson Refinery Inc | Platteville, CO 80651 | Oil & Gas Operator | Apr 1994 |
| 50 | Citation Oil & Gas Corp | Houston, TX 77269 | Oil & Gas Operator | Mar 2026 |
| 51 | Clinton Oil Company | Wichita, KS 67202 | Oil & Gas Operator | Apr 1980 |
| 52 | Columbine Exploration Corp | Englewood, CO 80111 | Oil & Gas Operator | Aug 1998 |
| 53 | Conoco Inc | Houston, TX 77252 | Oil & Gas Operator | Mar 2015 |
| 54 | Costilla Energy, Inc. | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 55 | Cotton Petroleum Corporation | Tulsa, OK 74102 | Oil & Gas Operator | Jan 2005 |
| 56 | Daube Company The | Ardmore, OK 73401 | Oil & Gas Operator | Jan 2026 |
| 57 | Davis Bobby J | Upton, WY 82730 | Oil & Gas Operator | Oct 1989 |
| 58 | Davis Oil Company | Denver, CO 80202 | Oil & Gas Operator | Jun 1988 |
| 59 | DCD Inc | Gillette, WY 82716 | Oil & Gas Operator | Aug 2003 |
| 60 | Decalta International Corp | Denver, CO 80202 | Oil & Gas Operator | Mar 2015 |
| 61 | Devon Energy Production Company, L.P. | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2026 |
| 62 | Diamond B Industries Inc | Belle Fourche, SD 57717 | Oil & Gas Operator | Apr 2010 |
| 63 | Dominion Oklahoma Texas Expl & Prod Inc | Oklahoma City, OK 73134 | Oil & Gas Operator | Aug 2013 |
| 64 | Duncan Oil Inc | Denver, CO 80210 | Oil & Gas Operator | Jun 2016 |
| 65 | Fancher Oil LLC | Greenwood, CO 80111 | Oil & Gas Operator | Nov 2006 |
| 66 | Felmont Oil Corporation | Walnut Creek, CA 94596-3568 | Oil & Gas Operator | Feb 1990 |
| 67 | Ferreira Oil Properties LLC | Carefree, AZ 85377 | Oil Operator | Apr 2014 |
| 68 | Finley Resources Inc | Fort Worth, TX 76113 | Oil & Gas Operator | Mar 2026 |
| 69 | Flahive Oil & Gas LLC | Golden, CO 80401 | Oil Operator | Oct 1995 |
| 70 | Flying J Oil & Gas Inc | North Salt Lake, UT 84054 | Oil & Gas Operator | Dec 2009 |
| 71 | Four-A Energy LLC | Cody, WY 82414 | Oil Operator | Feb 2026 |
| 72 | Fremont Energy Corporation | Oklahoma City, OK 73112 | Oil & Gas Operator | Dec 2004 |
| 73 | Fuel Exploration Inc | Denver, CO 80295 | Oil & Gas Operator | Jan 1992 |
| 74 | Gallagher Drilling Inc | Evansville, IN 47730 | Oil Operator | Dec 2020 |
| 75 | Gary-Williams Production Company | Denver, CO 80202 | Oil & Gas Operator | May 2000 |
| 76 | General Atlantic Resources Inc | Denver, CO 80202 | Oil & Gas Operator | Jan 2022 |
| 77 | Geodyne Operating Company | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2015 |
| 78 | Goldmark Engineering Inc | Casper, WY 82602 | Oil & Gas Operator | Oct 2004 |
| 79 | Graham Royalty LTD | Covington, LA 70434 | Oil & Gas Operator | Jul 2007 |
| 80 | Granite Creek Energy LLC | Cody, WY 82414 | Oil & Gas Operator | Jan 2026 |
| 81 | Grayling Resources LTD | Lakewood, CO 80235 | Oil & Gas Operator | Jul 2020 |
| 82 | Great Northern Drilling Company | Billings, MT 59103 | Oil & Gas Operator | Jun 2016 |
| 83 | H2oil Services LLC | | Oil Operator | Dec 2025 |
| 84 | Harper Oil Co. | Denver, CO 80217 | Oil & Gas Operator | Sep 2025 |
| 85 | Hedges Spencer | Casper, WY 82604 | Oil Operator | Mar 2024 |
| 86 | Hilcorp Energy Company | Houston, TX 77208 | Oil & Gas Operator | Mar 2026 |
| 87 | Holwell Drilling Company | | Oil Operator | Sep 1992 |
| 88 | Home Petroleum Corp | Victoria, TX 77902 | Oil & Gas Operator | Mar 2026 |
| 89 | Hondo Oil & Gas | Houston, TX 77042 | Oil & Gas Operator | Oct 1995 |
| 90 | HRM Resources II, LLC | Denver, CO 80202 | Oil & Gas Operator | Jan 2022 |
| 91 | HRM Resources LLC | Denver, CO 80202 | Oil & Gas Operator | Aug 2015 |
| 92 | Hrubetz Oil Co. | Dallas, TX 75225 | Oil Operator | Sep 1986 |
| 93 | Hudson Group LLC | Casper, WY 82601 | Oil & Gas Operator | Jul 2025 |
| 94 | Hughes Oil Company Inc | Odessa, TX 79765 | Oil & Gas Operator | Feb 2004 |
| 95 | Hunt Oil Company | Dallas, TX 75201 | Oil & Gas Operator | Mar 2026 |
| 96 | Iks Operating | Upton, WY 82703 | Oil & Gas Operator | Jul 2013 |
| 97 | Indian Creek Resources Inc | Loveland, CO 80538 | Oil & Gas Operator | Dec 2024 |
| 98 | Infield Discovery LLC | Madison, MS 39110 | Oil & Gas Operator | Sep 2025 |
| 99 | Integrated Energy Inc | Houston, TX 77002 | Oil & Gas Operator | Aug 2003 |
| 100 | Integrated Petroleum Corporation | Denver, CO 80202 | Oil Operator | Jan 2010 |