| 201 | Harken Exploration Company | Houston, TX 77079 | Oil & Gas Operator | Mar 2008 |
| 202 | Hawkins Oil & Gas, Inc. | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2016 |
| 203 | Headington Oil Company | Dallas, TX 75231 | Oil & Gas Operator | Dec 2016 |
| 204 | Headington Oil Company, L.P. | Dallas, TX 75231 | Oil & Gas Operator | Mar 2008 |
| 205 | Helmerich & Payne, Inc. | Tulsa, OK 74114 | Oil & Gas Operator | Nov 2024 |
| 206 | Hep Oil Company LTD | Gainesville, TX 76240 | Oil & Gas Operator | Mar 2012 |
| 207 | Highmark Energy Operating, LLC | Poynor, TX 75782 | Oil & Gas Operator | Mar 2025 |
| 208 | Highmount Operating LLC | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2014 |
| 209 | Holco Oil & Gas | Borger, TX 79008 | Oil & Gas Operator | Mar 2025 |
| 210 | Holmes Exploration, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Jun 2015 |
| 211 | Home Petroleum Corp | Victoria, TX 77902 | Oil & Gas Operator | Mar 2025 |
| 212 | Horizon Natural Gas Company | Tulsa, OK 74170 | Oil & Gas Operator | Oct 2024 |
| 213 | Horizon Natural Resources, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Jan 2019 |
| 214 | Horizon Oil & Gas Co. | Dallas, TX 75221 | Oil & Gas Operator | Jan 2005 |
| 215 | HS Resources, Inc. | Denver, CO 80202 | Oil & Gas Operator | Dec 2005 |
| 216 | Huber J M Corp | Edison, NJ 08837 | Oil & Gas Operator | Mar 2025 |
| 217 | Hugoton Energy Corporation | Oklahoma City, OK 73113 | Oil & Gas Operator | Dec 2019 |
| 218 | Hurd Enterprises, LTD. | San Antonio, TX 78209 | Oil & Gas Operator | Mar 2025 |
| 219 | I.T. Corporation | Arlington, TX 76016 | Oil & Gas Operator | Mar 2025 |
| 220 | Inexco Oil Company | Houston, TX 77210 | Oil & Gas Operator | Mar 2013 |
| 221 | Intercoast Oil And Gas Company | Tulsa, OK 74136 | Oil & Gas Operator | Jun 1997 |
| 222 | Interior Oil Corporation | Derby, KS 67037 | Oil & Gas Operator | Jan 2023 |
| 223 | Iron Sights Operating Inc | Stillwater, OK 74076 | Oil & Gas Operator | Jul 2022 |
| 224 | J-Brex Company | Amarillo, TX 79101 | Oil & Gas Operator | Mar 2025 |
| 225 | JCB II Enterprises LLC | Perryton, TX 79070 | Oil & Gas Operator | Jun 2023 |
| 226 | JCR, Jr - Operating, Inc. | Amarillo, TX 79114 | Oil & Gas Operator | Apr 2022 |
| 227 | Jiro | Stinnett, TX 79083 | Oil & Gas Operator | Mar 2025 |
| 228 | Jones Energy LLC | Oklahoma City, OK 73134 | Oil & Gas Operator | Dec 2024 |
| 229 | Jones Energy, LTD. | Austin, TX 78746 | Oil & Gas Operator | Sep 2013 |
| 230 | K. Stewart Petroleum Corporation | Oklahoma City, OK 73103 | Oil & Gas Operator | Jun 2001 |
| 231 | Kaiser-Francis Oil Company | Tulsa, OK 74121 | Oil & Gas Operator | Mar 2025 |
| 232 | Kato Operating Company | Bristow, OK 74010 | Oil & Gas Operator | Mar 2015 |
| 233 | KC Resources Inc | Snowmass VLG., CO 81615 | Oil & Gas Operator | Dec 2024 |
| 234 | KCS Medallion Resources, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Nov 2018 |
| 235 | KCS Resources, Inc. | Houston, TX 77002 | Oil & Gas Operator | Feb 2009 |
| 236 | KCS Resources, LLC | Houston, TX 77027 | Oil & Gas Operator | Feb 2017 |
| 237 | Kennedy & Mitchell, Inc. | Houston, TX 77084 | Oil & Gas Operator | Aug 2013 |
| 238 | Kerr-McGee Corporation | Dallas, TX 75380 | Oil & Gas Operator | Jan 2025 |
| 239 | Key Energy Of Colorado, Inc. | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2016 |
| 240 | King Operating Corporation | Fort Worth, TX 76147 | Oil & Gas Operator | Mar 2025 |
| 241 | Kismet Properties, Inc. | Amarillo, TX 79105 | Oil & Gas Operator | Mar 2025 |
| 242 | L & R Energy Corporation | Spearman, TX 79081 | Oil & Gas Operator | Nov 2014 |
| 243 | La VIda Energy Corporation | Midland, TX 79702 | Oil & Gas Operator | Apr 1993 |
| 244 | Laddex, LTD. | Amarillo, TX 79102 | Oil & Gas Operator | Mar 2025 |
| 245 | Laredo Petroleum, Inc. | Tulsa, OK 74120 | Oil & Gas Operator | Mar 2023 |
| 246 | Latex Petroleum Corp. | Houston, TX 77090 | Oil & Gas Operator | Aug 2012 |
| 247 | Latigo Petroleum Texas, LP | Houston, TX 77002 | Oil & Gas Operator | Feb 2009 |
| 248 | Latigo Petroleum, Inc. | Tulsa, OK 74119 | Oil & Gas Operator | Dec 2024 |
| 249 | Latigo Petroleum, LLC | Pampa, TX 79066 | Oil & Gas Operator | Mar 2025 |
| 250 | LDX Operating Company, LLC. | Amarillo, TX 79102 | Oil & Gas Operator | Mar 2025 |
| 251 | Le Norman Operating LLC | Oklahoma City, OK 73142 | Oil & Gas Operator | Nov 2019 |
| 252 | Lease Holders Acquisitions LLC | Yukon, OK 73099 | Gas Operator | Mar 2025 |
| 253 | Legacy Reserves Operating LP | Denver, CO 80201 | Oil & Gas Operator | Mar 2025 |
| 254 | Lera | Borger, TX 79007 | Oil & Gas Operator | Mar 2025 |
| 255 | Lime Rock Resources II-A, L.P. | Houston, TX 77002 | Oil & Gas Operator | Dec 2024 |
| 256 | Linn Operating, Inc. | Houston, TX 77002 | Oil & Gas Operator | May 2017 |
| 257 | Live Oak Gas Company | Dallas, TX 75251 | Oil & Gas Operator | Mar 2025 |
| 258 | Lomak Production Company | Fort Worth, TX 76102 | Oil & Gas Operator | Aug 1998 |
| 259 | Lone Tree Oil & Gas LLC | Greenwood VLG, CO 80111 | Oil & Gas Operator | Mar 2025 |
| 260 | Luxor Oil & Gas, Inc. | Pampa, TX 79066 | Oil & Gas Operator | Mar 2017 |
| 261 | Lytle Creek Operating, Inc. | Abilene, TX 79606 | Oil & Gas Operator | Mar 2025 |
| 262 | M E Klein & Associates, Inc. | Norman, OK 73070 | Oil & Gas Operator | Nov 2024 |
| 263 | Mac 5 Operating, LLC | Pampa, TX 79065 | Oil & Gas Operator | Feb 2021 |
| 264 | Mace, T. A. | Oklahoma City, OK 73127 | Oil & Gas Operator | Feb 2008 |
| 265 | Magnum Hunter Production, Inc. | Irving, TX 75014 | Oil & Gas Operator | Dec 2019 |
| 266 | Makar Production Company | Amarillo, TX 79118 | Oil & Gas Operator | Mar 2025 |
| 267 | Malson Oil Company | Crawford, OK 73638 | Oil & Gas Operator | Dec 2016 |
| 268 | Manti Operating Company | Covington, LA 70435 | Oil & Gas Operator | Mar 2025 |
| 269 | Marathon Oil Company | Houston, TX 77024 | Oil & Gas Operator | Jan 2025 |
| 270 | Maverick Brothers Operating,Inc. | Enid, OK 73702 | Oil & Gas Operator | Mar 2025 |
| 271 | Maxus Exploration Company | Dallas, TX 75201 | Oil & Gas Operator | Jan 1995 |
| 272 | Maxwell Resources Corporation | Oklahoma City, OK 73116-7746 | Oil & Gas Operator | Apr 2009 |
| 273 | McClure Oil Company, Inc. | Midland, TX 79701 | Oil & Gas Operator | Mar 2025 |
| 274 | McDaniel Company, Inc., The | Dallas, TX 75230 | Oil & Gas Operator | Mar 2025 |
| 275 | McGee, Tom Corporation | Booker, TX 79005 | Oil & Gas Operator | Dec 2024 |
| 276 | McKinney Operating Company | Canadian, TX 79014 | Gas Operator | May 2002 |
| 277 | McNic Oil & Gas Midcontinent,Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Jul 1999 |
| 278 | Medallion Petroleum, Inc. | Tulsa, OK 74103 | Oil & Gas Operator | Jan 2015 |
| 279 | Medallion Production Company | Tulsa, OK 74103 | Oil & Gas Operator | May 1997 |
| 280 | Meridian Oil Inc. | Houston, TX 77210 | Oil & Gas Operator | Aug 1996 |
| 281 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | Mar 2025 |
| 282 | Mewbourne Oil Company | Tyler, TX 75711 | Oil & Gas Operator | Mar 2025 |
| 283 | MFP Petroleum LTD. Partnership | Oklahoma City, OK 73142 | Oil & Gas Operator | Nov 2017 |
| 284 | Mge Resources, Inc. | Perryton, TX 79070 | Oil & Gas Operator | Dec 2024 |
| 285 | Mid-Continent Energy Operating Company | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2024 |
| 286 | Midgard Energy Company | The Woodlands, TX 77380 | Oil & Gas Operator | Dec 2014 |
| 287 | Midstates Petroleum Company LLC | Tulsa, OK 74103 | Oil & Gas Operator | May 2018 |
| 288 | Midway Operating Company, L.L.C. | Woodward, OK 73802 | Oil & Gas Operator | Mar 2025 |
| 289 | Midwestern Exploration Co. | Edmond, OK 73013 | Oil & Gas Operator | Nov 2024 |
| 290 | Miltex Oil Company | Boerne, TX 78006 | Oil & Gas Operator | Mar 2025 |
| 291 | Mitchell Ehrlich Oil & Gas, LLC | Austin, TX 78746 | Oil & Gas Operator | Mar 2025 |
| 292 | MJM Oil & Gas, Inc. | Dallas, TX 75201 | Oil & Gas Operator | Aug 2003 |
| 293 | Mobeetie Resource Dev LLC | Booker, TX 79005 | Oil & Gas Operator | Mar 2025 |
| 294 | Mobil Oil Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2016 |
| 295 | Mobil Producing TX. & N.M. Inc. | Spring, TX 77389 | Oil & Gas Operator | Mar 2025 |
| 296 | Mon Corp. | Pampa, TX 79066 | Oil & Gas Operator | Mar 2025 |
| 297 | Montgomery Petroleum, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Aug 2007 |
| 298 | MRR Oil Inc. | Perryton, TX 79070 | Oil & Gas Operator | Jun 2002 |
| 299 | Mustang Fuel Corp. Of Oklahoma | Oklahoma City, OK 73106 | Oil & Gas Operator | Nov 2016 |
| 300 | Myriad Resources Corporation | Pampa, TX 79066 | Oil & Gas Operator | Mar 2025 |