| 1 | B L Oil And Gas | Loco Hills, NM 88255 | Oil & Gas Operator | Aug 2010 |
| 2 | Babcock & Brown Energy Inc | Denver, CO 80202 | Oil & Gas Operator | Dec 2007 |
| 3 | Badger Oil Corporation | Lafayette, LA 70505 | Oil & Gas Operator | Nov 2011 |
| 4 | Badlands Energy-Utah, LLC | Denver, CO 80237 | Oil & Gas Operator | Feb 2018 |
| 5 | Badlands Production Company | Greenwood VIllage, CO 80111 | Oil & Gas Operator | Sep 2018 |
| 6 | Bainbridge Uinta LLC | Dallas, TX 75205 | Oil & Gas Operator | May 2021 |
| 7 | Ballard & Associates Inc | Billings, MT 59102-5406 | Oil & Gas Operator | Feb 2000 |
| 8 | Ballard Petroleum LLC | Billings, MT 59102-5406 | Oil & Gas Operator | Apr 2014 |
| 9 | Bar Mesa Resources Inc | Roosevelt, UT 84066 | Oil & Gas Operator | Sep 2012 |
| 10 | Barrett Resources Corporation | Denver, CO 80202 | Oil & Gas Operator | Aug 2003 |
| 11 | Basf Corporation | Houston, TX 77027 | Oil & Gas Operator | Nov 1992 |
| 12 | Bayless Robert L Producer | Denver, CO 80293 | Oil & Gas Operator | Sep 2003 |
| 13 | Beard, J / McIlnay & Assoc | Casper, WY 82604 | Oil & Gas Operator | Aug 1996 |
| 14 | Beartooth Oil & Gas Company | Billings, MT 59103 | Oil & Gas Operator | Sep 2025 |
| 15 | Belco Development Corporation | Tulsa, OK 74136 | Oil & Gas Operator | Feb 1994 |
| 16 | Belco Petroleum Corp | Grand Junction, CO | Oil & Gas Operator | Dec 1983 |
| 17 | Belnorth Petroleum Corporation | Midland, TX 79701 | Oil & Gas Operator | Feb 1991 |
| 18 | Benson-Montin-Greer DRL | Farmington, NM 87402 | Oil & Gas Operator | Oct 2025 |
| 19 | Berry Petroleum Company | Denver, CO 80202 | Oil & Gas Operator | Feb 2014 |
| 20 | Berry Petroleum Company LLC | Bakersfield, CA 93311 | Oil & Gas Operator | Sep 2025 |
| 21 | BHP Petroleum (Americas) | Houston, TX 77056-3020 | Oil & Gas Operator | Mar 1993 |
| 22 | BHP Petroleum Company Inc | Houston, TX 77057 | Oil & Gas Operator | Jun 2016 |
| 23 | Bill Barrett Corporation | Denver, CO 80202 | Oil & Gas Operator | Dec 2017 |
| 24 | Birch Corporation | Denver, CO 80217 | Oil & Gas Operator | Dec 1989 |
| 25 | Bishop Petroleum Corp | Arvada, CO 80002 | Oil & Gas Operator | Oct 1993 |
| 26 | Blue Tip Castlegate, Inc | Erie, KS 66733 | Gas Operator | Jun 2016 |
| 27 | Boardwalk Petroleum Inc | | Oil & Gas Operator | Dec 1983 |
| 28 | Bog Inc (Bowers) | Grand Junction, CO 81502 | Oil & Gas Operator | Jan 1989 |
| 29 | Bonneville Fuels Corp | Denver, CO 80290 | Oil & Gas Operator | Jun 2002 |
| 30 | Bow Valley Petroleum Inc | Denver, CO 80202 | Oil & Gas Operator | Apr 1996 |
| 31 | Bowers Oil & Gas, Inc. | Grand Junction, CO 81505-1097 | Oil & Gas Operator | Nov 2022 |
| 32 | BP America Production Company | Denver, CO 80202 | Oil & Gas Operator | Aug 2025 |
| 33 | Bridge Oil Company LP | Midland, TX 79702 | Oil & Gas Operator | May 1999 |
| 34 | Brinkerhoff Drilling Co | | Oil & Gas Operator | Jul 1975 |
| 35 | Broadhead, Walter | Grand Junction, CO 81502 | Oil & Gas Operator | Mar 2005 |
| 36 | Bta Oil Producers | Midland, TX 79701 | Oil & Gas Operator | Sep 2009 |
| 37 | Buckhorn Petroleum | | Oil & Gas Operator | Dec 1983 |
| 38 | Burlington Resources O&G | Midland, TX 79710-1810 | Oil & Gas Operator | Mar 1997 |
| 39 | Burr Oil & Gas | Farmington, NM 87499 | Oil & Gas Operator | Feb 2000 |
| 40 | Burton/Hawks Inc | Casper, WY 82602 | Oil & Gas Operator | Sep 1993 |
| 41 | Buttes Gas & Oil Co | | Oil & Gas Operator | Dec 2009 |
| 42 | Bwab Incorporated | Denver, CO 80202 | Oil & Gas Operator | Aug 1996 |