| 1 | L & B Oil Company Inc | Houston, TX 77019-3115 | Oil & Gas Operator | Mar 2025 |
| 2 | L & J Operating Inc | Gillette, WY 82718 | Oil & Gas Operator | Aug 2016 |
| 3 | L & R Drilling Company | Belle Fourche, SD 57717 | Oil & Gas Operator | Dec 1999 |
| 4 | L B Industries Inc | Englewood, CO 80112 | Oil & Gas Operator | Jun 2003 |
| 5 | L R Company | Casper, WY 82602 | Oil & Gas Operator | Sep 2007 |
| 6 | La Prele Exploration | | Oil & Gas Operator | Oct 1979 |
| 7 | Labarge Minerals Inc | Labarge, WY 83123 | Oil & Gas Operator | Jan 2020 |
| 8 | Ladd & Lukowicz | | Oil & Gas Operator | May 1983 |
| 9 | Lagniappe Interest Inc | Evergreen, CO 80439 | Oil & Gas Operator | Jun 2006 |
| 10 | Laguna Petroleum Company | Casper, WY 82601 | Oil & Gas Operator | Dec 1982 |
| 11 | Lakota Partnership | Denver, CO 80202 | Oil Operator | Oct 1990 |
| 12 | Lance Oil & Gas Company Inc | Kirtland, NM 87417 | Oil & Gas Operator | Mar 2013 |
| 13 | Langley Energy | Euless, TX 76040 | Gas Operator | Jan 2016 |
| 14 | Lappin Oil LLC | Douglas, WY 82633 | Oil & Gas Operator | Sep 2025 |
| 15 | Laramie Energy II LLC | Denver, CO 80202 | Oil & Gas Operator | Sep 2015 |
| 16 | Lario Oil & Gas Company | Odessa, TX 79762 | Oil & Gas Operator | Oct 2025 |
| 17 | Lasmo Energy Corporation | Tulsa, OK 74136 | Oil & Gas Operator | Jan 2024 |
| 18 | Lawson Oil Company | Buckeye, AR 85326 | Oil Operator | Mar 1996 |
| 19 | Lear Petroleum Exploration | | Oil & Gas Operator | Jul 2013 |
| 20 | Leclair-Westwood Inc | | Oil & Gas Operator | Mar 1982 |
| 21 | Leeman Don J | Oklahoma City, OK 73112 | Oil & Gas Operator | Sep 1998 |
| 22 | Legacy Energy Inc | Carpinteria, CA 93013 | Oil & Gas Operator | Jun 2012 |
| 23 | Legacy Reserves Operating LP | Denver, CO 80201 | Oil & Gas Operator | Oct 2025 |
| 24 | Levinson Partners Corporation | Denver, CO 80202 | Oil & Gas Operator | Jul 1995 |
| 25 | Lewis & Clark Exploration | | Oil Operator | Feb 1989 |
| 26 | Lewis Yale H | | Oil & Gas Operator | Aug 1986 |
| 27 | Lexicon Resources Corporation | | Oil & Gas Operator | Apr 1986 |
| 28 | Liberty Production Co | Houston, TX 77002 | Oil & Gas Operator | Nov 1994 |
| 29 | Liberty Resources Management Co LLC | Denver, CO 80202 | Oil & Gas Operator | Aug 2025 |
| 30 | Lilis Energy Inc | Denver, CO 80203 | Oil & Gas Operator | Aug 2017 |
| 31 | Lincero LLC | Sinclair, WY 82334 | Oil Operator | Sep 2025 |
| 32 | Linn Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Jan 2019 |
| 33 | Lissolo J W | Yuma, AZ 85365 | Oil & Gas Operator | Feb 2017 |
| 34 | Lissolo Timothy C | Newcastle, WY 82701 | Oil Operator | Sep 2025 |
| 35 | Llosu Corporation | Rawlins, WY 82301 | Oil & Gas Operator | Mar 2002 |
| 36 | Loco | Casper, WY 82602 | Oil & Gas Operator | Jul 2022 |
| 37 | Lodestone Operating | Portland, TX 78374 | Oil & Gas Operator | Jul 2025 |
| 38 | Loil Oil LLC | Golden, CO 80402 | Oil & Gas Operator | Aug 2025 |
| 39 | Lone Star Land And Energy II LLC | Dallas, TX 75214 | Oil & Gas Operator | Jan 2020 |
| 40 | Long Beach Oil Development Co | Glendale, CA 91203 | Oil & Gas Operator | Jun 2004 |
| 41 | Long Trust The | Kilgore, TX 75663 | Oil & Gas Operator | Aug 2008 |
| 42 | Longs Peak Resources LLC | Houston, TX 77019 | Oil & Gas Operator | Aug 2025 |
| 43 | Loral Operating LLC | Sheridan, WY 82801 | Gas Operator | Apr 2011 |
| 44 | Louisiana Land & Exploration Co. | Houston, TX 77210 | Oil & Gas Operator | Sep 2013 |
| 45 | Loundagin N B | Casper, WY 82602 | Oil & Gas Operator | Sep 2015 |
| 46 | Low D J | Littleton, CO 80127 | Oil Operator | Dec 1999 |
| 47 | Lowry Exploration Inc | Tulsa, OK 74119 | Oil & Gas Operator | Jun 2025 |
| 48 | Luff Exploration | Denver, CO 80203 | Oil & Gas Operator | Dec 2006 |
| 49 | Lusk Operating LLC | Denver, CO 80202 | Oil Operator | Jun 2017 |
| 50 | Lyco Operating Company | Dallas, TX 75206 | Gas Operator | Dec 1997 |