| 1 | 3tec Energy Corporation | Houston, TX 77002 | Oil & Gas Operator | Dec 2019 |
| 2 | Acadian Gas Pipeline System | | Oil Operator | Jan 2025 |
| 3 | Ada Oil Exploration Corp | | Oil & Gas Operator | Jan 1986 |
| 4 | Alamo Petroleum Company | | Oil & Gas Operator | Jun 1985 |
| 5 | Alliance Operating Corporation | | Oil & Gas Operator | Jan 1995 |
| 6 | Allwaste Oilfield Services Inc | | Oil Operator | May 1996 |
| 7 | Alpine Energy, Inc. | | Oil & Gas Operator | Dec 1999 |
| 8 | Alpine Expl. Companies, Inc. | | Oil & Gas Operator | Jan 2024 |
| 9 | Alta Mesa Services, LP | Houston, TX 77084 | Oil & Gas Operator | Oct 2025 |
| 10 | Amax Petroleum Corporation | Houston, TX 77042 | Oil & Gas Operator | Dec 2012 |
| 11 | Amerada Hess Corporation | Houston, TX 77252 | Oil & Gas Operator | Aug 2013 |
| 12 | American Coastal Energy, Inc. | Houston, TX 77225 | Oil & Gas Operator | May 2008 |
| 13 | American Quasar Petroleum Co. | Fort Worth, TX 76102 | Oil & Gas Operator | Apr 2014 |
| 14 | Amoco Production Co. | Houston, TX 77253 | Oil & Gas Operator | Jun 2015 |
| 15 | Anderson Exploration Co., Inc. | | Oil & Gas Operator | Sep 2023 |
| 16 | Apache Corporation | Houston, TX 77042 | Oil & Gas Operator | Oct 2025 |
| 17 | Arco O & G Co-Div Atl Rich Co | | Oil & Gas Operator | Feb 1994 |
| 18 | Badger Oil Corporation | Lafayette, LA 70505 | Oil & Gas Operator | Nov 2011 |
| 19 | Bargo Energy Corporation | | Oil & Gas Operator | Apr 2000 |
| 20 | Bayou Resources, Inc. | Houston, TX 77056 | Oil & Gas Operator | Jan 2015 |
| 21 | Bellwether Exploration Company | Houston, TX 77010 | Oil & Gas Operator | May 2001 |
| 22 | Benton Oil & Gas Company Of La | | Oil & Gas Operator | Apr 1997 |
| 23 | Beta Oil Inc | | Oil Operator | Feb 1986 |
| 24 | Beta Operating, Inc | | Oil & Gas Operator | May 2001 |
| 25 | BHP Petroleum Company Inc | Houston, TX 77057 | Oil & Gas Operator | Jun 2016 |
| 26 | Black Gold Production Company | | Oil & Gas Operator | Feb 1998 |
| 27 | Blakely Land & Exploration Co. | | Oil & Gas Operator | Apr 1991 |
| 28 | Borden, Inc. | Columbus, OH 43215 | Oil & Gas Operator | May 1990 |
| 29 | BP America Production Company | Denver, CO 80202 | Oil & Gas Operator | Jun 2025 |
| 30 | Brammer Engineering, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Oct 2025 |
| 31 | Brazos River LLC | | Oil & Gas Operator | Apr 2002 |
| 32 | Brehm Exploration, Inc. | | Oil & Gas Operator | Mar 1995 |
| 33 | Burlington Res Oil & Gas Co | | Oil & Gas Operator | Dec 2000 |
| 34 | Burlington Res Oil & Gas LP | | Oil & Gas Operator | Mar 2013 |
| 35 | Cabot Oil & Gas Corporation | Houston, TX 77024 | Oil & Gas Operator | Jun 2025 |
| 36 | Camex Operating Company | | Oil & Gas Operator | Dec 2024 |
| 37 | Camex, Inc. | | Oil & Gas Operator | Jun 1992 |
| 38 | Carl Oil & Gas Co. | Bakersfield, CA 93309 | Oil & Gas Operator | Dec 1995 |
| 39 | Carrizo Oil & Gas, Inc. | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 40 | Carrollton Resources Corp. | | Oil & Gas Operator | Sep 2000 |
| 41 | Caskids Operating Company | Houston, TX 77027 | Oil & Gas Operator | Oct 2025 |
| 42 | Caspen Operating Company | Somerset, TX 78069 | Oil & Gas Operator | Mar 2008 |
| 43 | Castex Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 44 | Cathexis Oil & Gas, LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2014 |
| 45 | Century Exploration Houston, Inc | The Woodlands, TX 77380 | Oil & Gas Operator | Oct 2011 |
| 46 | Century Exploration N.O., Inc. | | Oil & Gas Operator | Sep 2011 |
| 47 | Chevron USA Inc | Midland, TX 79706 | Oil & Gas Operator | Oct 2025 |
| 48 | Cholla Resources, Inc. | Denver, CO 80202 | Oil & Gas Operator | Jan 1997 |
| 49 | Cities Service Company | | Oil & Gas Operator | Mar 1983 |
| 50 | Cities Service Oil & Gas Corp | | Oil & Gas Operator | Mar 1988 |
| 51 | Cities Service Oil Co. | | Oil & Gas Operator | Dec 1986 |
| 52 | Clayton Williams Energy, Inc. | Houston, TX 77070 | Oil & Gas Operator | Apr 2017 |
| 53 | CMS Nomeco Oil & Gas Co. | Jackson, MI 49201 | Oil & Gas Operator | Jan 2015 |
| 54 | Cochon Properties, LLC | | Oil & Gas Operator | Aug 2016 |
| 55 | Cockrell Oil Corporation | Houston, TX 77002-7348 | Oil & Gas Operator | Feb 2001 |
| 56 | Collet Oil Ventures, Inc. | Denver, CO 80217 | Oil & Gas Operator | Jun 2004 |
| 57 | Columbia Gulf Transmission Co. | | Oil Operator | Dec 2014 |
| 58 | Columbia Gulf Transmission Company, LLC | | Oil Operator | Jan 2025 |
| 59 | Conoco Inc. | Houston, TX 77252 | Oil & Gas Operator | Mar 2015 |
| 60 | Conquest Exploration Co. | | Oil & Gas Operator | Mar 1992 |
| 61 | Continental Operating Co. | Houston, TX 77024 | Oil & Gas Operator | Oct 2025 |
| 62 | Corenergy Operating Group, LLC | Houston, TX 77074 | Oil & Gas Operator | Oct 2025 |
| 63 | Crescent DRLG & DVLPMNT, Inc. | | Oil & Gas Operator | Oct 1992 |
| 64 | Crosstex Lig, LLC | | Oil Operator | Mar 2014 |
| 65 | CSL Exploration, LP | Houston, TX 77002 | Oil & Gas Operator | Apr 2018 |
| 66 | Cxy Energy, Inc. | Dallas, TX 75251 | Oil & Gas Operator | Nov 2000 |
| 67 | Cypress Gas Pipeline Company | | Oil Operator | Dec 1998 |
| 68 | Cypress Gas Pipeline, LLC | | Oil Operator | Sep 2019 |
| 69 | D C Bintliff & W W F Oil Corp. | | Oil & Gas Operator | Dec 1989 |
| 70 | Dailey Oil And Gas LLC | | Oil & Gas Operator | Jun 2019 |
| 71 | Damson Oil Corporation | Houston, TX 77210 | Oil & Gas Operator | Mar 2005 |
| 72 | Dan A. Hughes Company | | Oil & Gas Operator | Dec 2005 |
| 73 | Davis Oil Company | Denver, CO 80202 | Oil & Gas Operator | Jun 1988 |
| 74 | Daylight Petroleum LLC | Houston, TX 77052 | Oil & Gas Operator | Oct 2025 |
| 75 | Delta Operating Corporation | | Oil & Gas Operator | Feb 2024 |
| 76 | Denbury Management, Inc. | Dallas, TX 75252 | Oil & Gas Operator | Dec 1999 |
| 77 | Denbury Onshore, LLC | Plano, TX 75024 | Oil & Gas Operator | Oct 2025 |
| 78 | Denbury Resources Inc. | Plano, TX 75024 | Oil & Gas Operator | Dec 2003 |
| 79 | Denovo Oil & Gas, Inc. | Houston, TX 77210 | Oil & Gas Operator | May 1995 |
| 80 | Destin Operating Company, Inc. | | Oil & Gas Operator | Jan 2023 |
| 81 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 82 | DLB Oil & Gas, Inc. | Big Lake, TX 76932 | Oil & Gas Operator | Oct 2025 |
| 83 | Dominion Exploration & Production Inc | Houston, TX 77060 | Oil & Gas Operator | Apr 2015 |
| 84 | Dore-Dyn Production Co., Inc. | | Oil & Gas Operator | Jul 1993 |
| 85 | Duncan Energy Company | Denver, CO 80202 | Oil & Gas Operator | Mar 2008 |
| 86 | Dune Operating Company | Dallas, TX 75201 | Oil & Gas Operator | Jun 2016 |
| 87 | Dunhill Resources, Inc. | | Oil & Gas Operator | Nov 2005 |
| 88 | Dynamic Exploration PTRS, LLC | | Oil & Gas Operator | Nov 2024 |
| 89 | Dynamic Offshore Resources, LLC | Houston, TX 77042 | Oil & Gas Operator | Oct 2025 |
| 90 | Ed I. Estis | | Oil & Gas Operator | Sep 1998 |
| 91 | Edgewater Oil Co. Inc. | | Oil & Gas Operator | Jul 1995 |
| 92 | Edisto Resources Corp | Houston, TX 77057 | Oil & Gas Operator | Oct 1999 |
| 93 | Edwin L. Cox | | Oil & Gas Operator | May 1986 |
| 94 | El Paso E&P Company, L.P. | Houston, TX 77002 | Oil & Gas Operator | Mar 2013 |
| 95 | El Paso Production Gom, Inc. | | Oil & Gas Operator | Nov 2005 |
| 96 | Elad Petroleum Corporation | | Oil Operator | Jun 2005 |
| 97 | Elf Aquitaine Inc | Houston, TX 77002 | Oil & Gas Operator | May 1991 |
| 98 | Elliott Oil & Gas Company | The Woodlands, TX 77380 | Oil & Gas Operator | Sep 2006 |
| 99 | Enbridge Offshore Pipelines(Seacrest) LP | | Oil Operator | Oct 2009 |
| 100 | Energy Xxi Gulf Coast, Inc. | | Oil & Gas Operator | Dec 2008 |