| 1 | H & L Operating Co LLP | Amarillo, TX 79114 | Oil & Gas Operator | Aug 2022 |
| 2 | H & L Operating Company | Amarillo, TX 79114 | Oil & Gas Operator | Feb 2020 |
| 3 | H G & G Inc | Edmond, OK 73034 | Oil & Gas Operator | Jan 2006 |
| 4 | H.L.S. Energy Co., Inc. | Uvalde, TX 78801 | Oil & Gas Operator | Aug 2003 |
| 5 | H2ok LLC | | Oil & Gas Operator | Feb 2024 |
| 6 | H2ox Operating LLC | | Oil Operator | Feb 2024 |
| 7 | Hadson Petro USA Inc | | Oil & Gas Operator | Nov 2016 |
| 8 | Hadson Petroleum Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2015 |
| 9 | Halcon Holdings Inc | Ada, OK 74820 | Oil & Gas Operator | Nov 2018 |
| 10 | Hall Energy Company LLC | Oklahoma City, OK 73120-5020 | Oil & Gas Operator | Jul 2022 |
| 11 | Halliburton Oil Producing Co. | Duncan, OK 73534 | Oil & Gas Operator | Apr 2016 |
| 12 | Ham Oil Company, LLC | | Oil Operator | Sep 2022 |
| 13 | Harbert Energy Corp | Irving, TX 75015-2510 | Oil & Gas Operator | Feb 1993 |
| 14 | Harding & Shelton Inc | Oklahoma City, OK 73104-2410 | Oil & Gas Operator | Jan 2024 |
| 15 | Hazelwood Prod & Exp Co LLC | Oklahoma City, OK 73116-9037 | Oil & Gas Operator | Dec 2023 |
| 16 | Headington Energy Corporation | Dallas, TX 75231 | Oil & Gas Operator | Aug 1992 |
| 17 | Headington Oil Company | Dallas, TX 75231 | Oil & Gas Operator | Dec 2016 |
| 18 | Headington Oil Company LLC | Dallas, TX 75204 | Oil & Gas Operator | Apr 2016 |
| 19 | Heartland Exploration Inc | Edmond, OK 73013 | Oil & Gas Operator | Dec 2015 |
| 20 | Heartlands Development Co Inc | Bristow, OK 74010-3826 | Oil & Gas Operator | May 2017 |
| 21 | Heath B M | | Oil & Gas Operator | Feb 1994 |
| 22 | Heath Oil Company | Washington, OK 73093-4702 | Oil & Gas Operator | Jan 2024 |
| 23 | Helmerich & Payne, Inc. | Tulsa, OK 74114 | Oil & Gas Operator | Jan 2024 |
| 24 | Hess Corporation | Houston, TX 77010 | Oil & Gas Operator | Aug 2017 |
| 25 | Hibbert R E Estate Of | Houston, TX 77002-3211 | Oil & Gas Operator | Apr 2015 |
| 26 | High Sierra Crude Oil& Marketing LLC | Ardmore, OK 73401 | Oil Operator | Nov 2013 |
| 27 | Highmark Energy Operating, LLC | Poynor, TX 75782 | Oil & Gas Operator | Apr 2024 |
| 28 | Hill Oil Company Inc | | Oil & Gas Operator | Jan 2024 |
| 29 | Hill Resources Inc | | Oil & Gas Operator | Nov 2022 |
| 30 | Hinkle Engineering, Inc. | Oklahoma City, OK 73112 | Oil & Gas Operator | Nov 2016 |
| 31 | Hinkle Oil And Gas Inc | Oklahoma City, OK 73112-4275 | Oil & Gas Operator | Feb 2024 |
| 32 | HK Energy Operating, LLC | Houston, TX 77002 | Oil & Gas Operator | May 2023 |
| 33 | Hodgden Operating Co., Inc. | Enid, OK 73702 | Oil & Gas Operator | Feb 2024 |
| 34 | Holden Energy Corporation | Ardmore, OK 73401 | Oil & Gas Operator | Mar 2015 |
| 35 | Holke Dave Consulting Inc | Meridian, ID 83646-4812 | Oil & Gas Operator | Jan 2024 |
| 36 | Home-Stake Royalty Corp., The | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2014 |
| 37 | Hondo Oil & Gas Company | Roswell, NM 88202 | Oil & Gas Operator | Aug 2006 |
| 38 | Horizon Natural Gas Company | Tulsa, OK 74170 | Oil & Gas Operator | Jan 2024 |
| 39 | Horizon Natural Resources, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Jan 2019 |
| 40 | Horizon Oil & Gas Co. | Dallas, TX 75221 | Oil & Gas Operator | Jan 2005 |
| 41 | HRC Production Co | Houston, TX 77002 | Oil & Gas Operator | Jan 2024 |
| 42 | Huber J M Corp | Edison, NJ 08837 | Oil & Gas Operator | Apr 2024 |
| 43 | Hughes George B | Asher, OK 74826-0165 | Oil & Gas Operator | Mar 2011 |
| 44 | Hugoton Energy Corporation | Oklahoma City, OK 73113 | Oil & Gas Operator | Dec 2019 |
| 45 | Huitt Joe A | Tulsa, OK 74103 | Oil & Gas Operator | May 2001 |
| 46 | Hunt Engineering Inc | Norman, OK 73069-4093 | Oil & Gas Operator | Feb 2019 |
| 47 | Huntington Energy LLC | Oklahoma City, OK 73116 | Oil & Gas Operator | Apr 2024 |
| 48 | Hunton Oil & Gas Corporation | Oklahoma City, OK 73154-0191 | Oil & Gas Operator | May 2019 |
| 49 | Hunton Operating LLC | Oklahoma City, OK 73154-0191 | Oil & Gas Operator | Feb 2024 |
| 50 | Hy-Carb Energy Inc | | Oil & Gas Operator | Feb 2009 |