| 1 | 4W Ranch | | Oil & Gas Operator | Dec 2008 |
| 2 | Aberdeen Petroleum (USA) Inc. | | Oil & Gas Operator | Jul 1993 |
| 3 | Abraxas Petroleum Corporation | San Antonio, TX 78258 | Oil & Gas Operator | Mar 2020 |
| 4 | Adams Don And Associates | | Oil & Gas Operator | Dec 2020 |
| 5 | Adobe Resources Corporation | Midland, TX 79701 | Oil & Gas Operator | Dec 2000 |
| 6 | Aethon Energy Operating LLC | Dallas, TX 75251 | Oil & Gas Operator | Dec 2020 |
| 7 | Aexco Petroleum Inc | Denver, CO 80202 | Oil & Gas Operator | Jan 2020 |
| 8 | Agnew-Sullivan Inc | | Oil Operator | Dec 2003 |
| 9 | Alexander Energy Corporation | Oklahoma City, OK BAD ADDR | Oil & Gas Operator | Mar 2015 |
| 10 | Allen And Crouch | | Oil & Gas Operator | Dec 2019 |
| 11 | Allen And Schramm Inc | | Oil & Gas Operator | Dec 1989 |
| 12 | Alpha Coal West Inc | | Oil & Gas Operator | Dec 2019 |
| 13 | Alpha Petrovision Us Inc | Canada, 100 | Oil & Gas Operator | May 2013 |
| 14 | Altex Oil Company | | Oil & Gas Operator | Dec 1995 |
| 15 | Am-West Petroleum Inc | | Oil & Gas Operator | Dec 2016 |
| 16 | Amarex Inc | | Oil & Gas Operator | Dec 1996 |
| 17 | Amax Oil & Gas Inc. | Houston, TX BAD ADDR | Oil & Gas Operator | Mar 2009 |
| 18 | Ambrit Energy Corp. | | Oil & Gas Operator | May 1999 |
| 19 | American Eagle Oil | | Oil & Gas Operator | Dec 2010 |
| 20 | American Energy Partners Inc | Allen, TX 75013 | Oil & Gas Operator | Dec 2011 |
| 21 | American Exploration Company | Houston, TX 77010-3088 | Oil & Gas Operator | Jan 2000 |
| 22 | Amplify Energy Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2020 |
| 23 | Ampolex Wy Inc | | Oil Operator | Dec 1995 |
| 24 | Anadarko E&P Onshore LLC | Houston, TX 77046 | Oil & Gas Operator | Dec 2020 |
| 25 | Anadarko Minerals, Inc. | Oklahoma City, OK 73102-8606 | Oil & Gas Operator | Jan 2020 |
| 26 | Anadarko Petroleum Corporation | Houston, TX 77251-1330 | Oil & Gas Operator | Dec 2019 |
| 27 | Anchor Bay Corporation | Denver, CO 80202 | Oil & Gas Operator | Dec 2007 |
| 28 | Anderson And Wells Oil Co | | Oil & Gas Operator | Dec 2006 |
| 29 | Anderson Management Company | | Oil & Gas Operator | Dec 2014 |
| 30 | Anderson Oil Company | Burkburnett, TX 76354-0576 | Oil & Gas Operator | Oct 2015 |
| 31 | Anr Production Company | Denver, CO 80201-0749 | Oil & Gas Operator | Sep 2017 |
| 32 | Anschutz Corporation, The | Denver, CO 80202 | Oil & Gas Operator | Sep 2016 |
| 33 | Anschutz Exploration Corporation | Denver, CO 80202 | Oil & Gas Operator | Mar 2020 |
| 34 | Anschutz Oil Company LLC | | Oil & Gas Operator | Dec 2019 |
| 35 | Anschutz Pinedale Corporation | | Oil & Gas Operator | Dec 2014 |
| 36 | Ant Hills Production | | Oil & Gas Operator | Dec 2019 |
| 37 | Antelope Energy Company LLC | Denver, CO 80202 | Oil & Gas Operator | Dec 2020 |
| 38 | Antelope Resources Inc | Billings, MT 59101 | Oil Operator | May 2017 |
| 39 | Antler Energy LLC | | Oil & Gas Operator | Dec 2019 |
| 40 | Apache Corporation | Houston, TX 77056 | Oil & Gas Operator | Mar 2020 |
| 41 | Apx Western Corporation | | Oil & Gas Operator | Dec 1991 |
| 42 | Aquarius Oil And Gas | | Oil & Gas Operator | Dec 2016 |
| 43 | Arch Oil & Gas Company | Midland, TX 79702 | Oil & Gas Operator | Jan 1992 |
| 44 | Argent Energy (Us) Holdings Inc | Sugar Land, TX 77479 | Oil & Gas Operator | Nov 2019 |
| 45 | Argentia Operating Company | | Oil Operator | Dec 1991 |
| 46 | Arjay Oil Company | | Oil Operator | Dec 1999 |
| 47 | Arnell Oil Company | | Oil Operator | Dec 2020 |
| 48 | Asher Associates Inc | Centennial, CO 80112 | Oil Operator | Aug 2016 |
| 49 | Atasca Resources, Inc. | Houston, TX 77219 | Oil & Gas Operator | Mar 2020 |
| 50 | Atlantic Oil And Gas Development LLC | | Oil Operator | Dec 2019 |
| 51 | Atlantic Oil Corporation | | Oil & Gas Operator | Dec 1982 |
| 52 | Atlantic Richfield Company | Plano, TX 75094-1744 | Oil & Gas Operator | Nov 2016 |
| 53 | Atomic Oil & Gas LLC | | Oil & Gas Operator | Dec 2012 |
| 54 | Atx Energy Partners LLC | | Oil & Gas Operator | Dec 2019 |
| 55 | Augustus Energy Partners LLC | Billings, MT 59102 | Oil & Gas Operator | Oct 2013 |
| 56 | Aztec Gas And Oil Corporation | Elephant Butte, NM 87935-0370 | Oil & Gas Operator | Mar 2005 |
| 57 | B3T LLC | | Oil Operator | Dec 2020 |
| 58 | Baldes Henry | | Oil Operator | Dec 1998 |
| 59 | Balidor Oil & Gas LLC | | Oil & Gas Operator | Dec 2020 |
| 60 | Ballard Petroleum Holdings LLC | Billings, MT 59104 | Oil & Gas Operator | Jan 2020 |
| 61 | Banding M R Inc | Gillette, WY 82717 | Oil & Gas Operator | Dec 2020 |
| 62 | Baney Well Service Inc | | Oil Operator | Jun 2016 |
| 63 | Banta And Haigh | | Oil Operator | Dec 1984 |
| 64 | Basin Resources Corporation | | Oil Operator | Dec 2012 |
| 65 | Bass Enterprises Production Co | Fort Worth, TX 76102 | Oil & Gas Operator | Jun 2012 |
| 66 | Bass Petroleum Inc | Austin, TX 78716 | Oil & Gas Operator | Mar 2020 |
| 67 | Bataa Oil Inc | Arvada, CO 80005 | Oil & Gas Operator | Dec 2020 |
| 68 | Bates Creek Oil | | Oil Operator | Dec 1986 |
| 69 | Bayless, Robert L Producer | Denver, CO 80293 | Oil & Gas Operator | Sep 2003 |
| 70 | Bayswater Exploration & Production, LLC | Clovis, CA 93612-1058 | Oil & Gas Operator | Jan 2020 |
| 71 | Baytex Energy USA LLC | | Oil & Gas Operator | Dec 2014 |
| 72 | Bear Oil And Gas Inc | | Oil & Gas Operator | Dec 2016 |
| 73 | Bearcat Energy LLC (Colorado) | | Oil & Gas Operator | Dec 2017 |
| 74 | Beartooth Oil & Gas Company | Billings, MT 59103 | Oil & Gas Operator | Dec 2020 |
| 75 | Belden & Blake Corporation | North Canton, OH 44720-0500 | Oil & Gas Operator | Dec 2016 |
| 76 | Bell Resources Inc | | Oil & Gas Operator | Dec 2014 |
| 77 | Benchmark Energy LLC | Pratt, KS 67124 | Oil & Gas Operator | Dec 2016 |
| 78 | Benson-Montin-Greer DRLG Corp | Farmington, NM 87402 | Oil & Gas Operator | Jan 2020 |
| 79 | Berco Resources LLC | | Oil & Gas Operator | Dec 2006 |
| 80 | Beren Corporation | Wichita, KS 67206 | Oil & Gas Operator | Dec 2020 |
| 81 | Berenergy Corporation | Denver, CO 80203 | Oil & Gas Operator | Jan 2020 |
| 82 | BHB Oil Partners LLC | | Oil & Gas Operator | Dec 2020 |
| 83 | BHP Petroleum (USA) Inc | | Gas Operator | Dec 1990 |
| 84 | BHP Petroleum Company Inc | Houston, TX 77057 | Oil & Gas Operator | Nov 2004 |
| 85 | Big Chief Exploration | | Oil & Gas Operator | Dec 1994 |
| 86 | Big Muddy Operating LLC | | Oil Operator | Dec 2020 |
| 87 | Bighorn Gas Operating Limited Partnner | | Oil & Gas Operator | Dec 2011 |
| 88 | Bill Barrett Corporation | Denver, CO 80202 | Oil & Gas Operator | Dec 2017 |
| 89 | Black Bear Oil Corporation | Las Vegas, NV 89128-3636 | Oil & Gas Operator | Dec 2020 |
| 90 | Black Coal Resources Company | | Oil & Gas Operator | Dec 1991 |
| 91 | Black Diamond Energy Inc | | Gas Operator | Dec 2016 |
| 92 | Black Diamond Energy Of Delaware Inc | | Oil & Gas Operator | Dec 2020 |
| 93 | Black Hills Exploration & Production Inc | | Oil & Gas Operator | Dec 2018 |
| 94 | Black Jack Oil Co Inc | | Oil & Gas Operator | Dec 2019 |
| 95 | Black Thunder Oil LLC | | Oil Operator | Dec 2019 |
| 96 | Blackjack Oil, Inc. | Las Vegas, NV 89128 | Oil & Gas Operator | Jun 2019 |
| 97 | Blackstone Operating Inc | | Gas Operator | Dec 2009 |
| 98 | Blake Production LLC | | Oil & Gas Operator | Dec 2020 |
| 99 | BLM | Norman, OK 73072 | Gas Operator | Dec 2010 |
| 100 | Blue Tip Energy Wyoming Inc | | Oil & Gas Operator | Dec 2016 |