| 201 | Harrison, Sam G. Oil, Inc. | Houston, TX 77019 | Oil & Gas Operator | Nov 2019 |
| 202 | Hart & McFarland | Vivian, LA 71082 | Oil & Gas Operator | Apr 2025 |
| 203 | Hart Petroleum Services, Inc | Robstown, TX 78380 | Oil & Gas Operator | Apr 2025 |
| 204 | Hartel, Inc. | Abilene, TX 79601 | Oil & Gas Operator | Aug 1997 |
| 205 | Harter, Ron | Midland, TX 79702 | Oil & Gas Operator | Apr 2025 |
| 206 | Hartoil Corporation | Post, TX 79356 | Oil & Gas Operator | Apr 2025 |
| 207 | Harvard Petroleum Company, LLC | Roswell, NM 88202 | Oil & Gas Operator | Apr 2025 |
| 208 | Harvard Petroleum Corporation | Roswell, NM 88201 | Oil & Gas Operator | Dec 2004 |
| 209 | Harvest Operating Company, Inc. | Cisco, TX 76437 | Oil & Gas Operator | Dec 1997 |
| 210 | Harvest Petroleum Inc. | Frisco, TX 75033 | Oil & Gas Operator | Apr 2025 |
| 211 | Harvey Brothers Oil & Gas | Corpus Chrsti, TX 78408 | Oil & Gas Operator | Jul 2004 |
| 212 | Harvey, James W. | Wichita Falls, TX 76301 | Oil & Gas Operator | Mar 2008 |
| 213 | Harvey, Mike W. Oil & Gas | Corpus Chrsti, TX 78408 | Oil & Gas Operator | Aug 2003 |
| 214 | Harvey, Robert E., Jr. | Nixon, TX 78140 | Oil & Gas Operator | Oct 2003 |
| 215 | Harvick Oil Co. | Albany, TX 76430 | Oil & Gas Operator | Feb 2009 |
| 216 | Harvick, George R. | Albany, TX 76430 | Oil & Gas Operator | Apr 2025 |
| 217 | Harwell Enterprises | Loveland, CO 80537 | Gas Operator | Nov 2019 |
| 218 | Harwell Enterprises Inc. | Weatherford, TX 76086 | Oil & Gas Operator | Jan 2005 |
| 219 | Harwood Exploration, Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Aug 1995 |
| 220 | Haskit, Kendall | Kyle, TX 78640 | Oil & Gas Operator | Apr 2025 |
| 221 | Hassie Hunt Expl. Company | Dallas, TX 75201 | Oil & Gas Operator | Aug 2008 |
| 222 | Hastings, J. W. Oil Co. | Wichita Falls, TX 76301 | Oil & Gas Operator | Mar 2010 |
| 223 | Hat Creek Energy LLC | Denver, CO 80209 | Oil & Gas Operator | Jun 2019 |
| 224 | Hat Oil & Gas, Inc. | Slaton, TX 79364 | Oil & Gas Operator | Feb 2002 |
| 225 | Hatcher, Ray | Burkburnett, TX 76354 | Oil & Gas Operator | Jun 2002 |
| 226 | Hatler Oil Company, Inc. | Graham, TX 76450 | Oil & Gas Operator | Sep 2000 |
| 227 | Havens Oil Company | Early, TX 76803 | Oil & Gas Operator | Dec 2024 |
| 228 | Haverkamp, Floyd | Muenster, TX 76252 | Oil & Gas Operator | Oct 2001 |
| 229 | Havins Energy | Burkburnett, TX 76354 | Oil & Gas Operator | May 2006 |
| 230 | Hawk Exploration And Production | Corpus Chrsti, TX 78412 | Oil & Gas Operator | Oct 1995 |
| 231 | Hawk Oil Co. | Luling, TX 78648 | Oil & Gas Operator | Aug 2003 |
| 232 | Hawk Petroleum, L L C | San Diego, TX 78384 | Oil & Gas Operator | Apr 2025 |
| 233 | Hawk Well Service | Borger, TX 79007 | Oil & Gas Operator | Apr 2025 |
| 234 | Hawk-Hill Operating Company, LLC | Plano, TX 75093 | Oil & Gas Operator | Jun 2009 |
| 235 | Hawkbend LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Apr 2025 |
| 236 | Hawkeye Drilling Co. | Waskom, TX 75692 | Oil & Gas Operator | Feb 2023 |
| 237 | Hawkeye Transmission Company | Dallas, TX 75244 | Oil & Gas Operator | Jun 2000 |
| 238 | Hawkins Energy Corporation | Austin, TX 78711 | Oil & Gas Operator | Apr 1997 |
| 239 | Hawkins Oil & Gas Company | Richardson, TX 75080 | Oil & Gas Operator | Apr 2025 |
| 240 | Hawkins Oil & Gas Inc | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2016 |
| 241 | Hawkins Oil, L.L.C. | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2024 |
| 242 | Hawkins, B. O. | Aspermont, TX 79502 | Oil & Gas Operator | Apr 2025 |
| 243 | Hawkins, G. A. | Graham, TX 76450 | Oil & Gas Operator | Dec 2013 |
| 244 | Hawkwood Energy Operating, LLC | Houston, TX 77224 | Oil & Gas Operator | Apr 2022 |
| 245 | Hawn Bros. & Venus Oil Co. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Aug 1995 |
| 246 | Hawn Brothers | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Apr 2003 |
| 247 | Hawn Brothers Company | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Jan 2003 |
| 248 | Hawthorn Energy Partners, LLC | Nichols Hill, OK 73116 | Oil & Gas Operator | Apr 2025 |
| 249 | Hawthorne Oil And Gas Corp. | Houston, TX 77227 | Oil & Gas Operator | Sep 1993 |
| 250 | Hay Creek Investments, L.L.C. | Santa Anna, TX 76878 | Oil Operator | Jul 2018 |
| 251 | Hayabusa Energy USA, LLC | Pampa, TX 79065 | Oil & Gas Operator | Apr 2025 |
| 252 | Hayes Oil & Gas Co. | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2005 |
| 253 | Hayes, Marshall A. III | Chilton, TX 76632 | Oil & Gas Operator | Apr 2025 |
| 254 | Haylan Oil Company | Midland, TX 79710 | Oil & Gas Operator | Jan 2000 |
| 255 | Haynes & Shirley Production Co. | Iowa Park, TX 76367 | Oil & Gas Operator | Apr 2025 |
| 256 | Haynes Production Company, Inc. | Brownwood, TX 76801 | Oil & Gas Operator | Dec 2006 |
| 257 | Haynie Drilling Co. Inc. | Corsicana, TX 75151 | Oil & Gas Operator | Dec 2011 |
| 258 | Haynie Energy Services LLC | Wortham, TX 76693 | Oil Operator | Apr 2025 |
| 259 | Hays & Boydston | Graham, TX 76450 | Oil & Gas Operator | Mar 1994 |
| 260 | Hays & Croker Partnership | Graham, TX 76450 | Oil & Gas Operator | Apr 2025 |
| 261 | Hays Partnership | Graham, TX 76450 | Oil & Gas Operator | Apr 2025 |
| 262 | Hays, David H. | Olney, TX 76374 | Oil & Gas Operator | Dec 1995 |
| 263 | Hays, John H. | Graham, TX 76450 | Oil & Gas Operator | Apr 2025 |
| 264 | Hays, Mrs. Earl (Cora) | Big Spring, TX 79720 | Oil & Gas Operator | Apr 2005 |
| 265 | Hays, T.G. Petroleum Expl., Inc. | Corpus Chrsti, TX 78476 | Oil & Gas Operator | Dec 1994 |
| 266 | Haywood, Paul M. Jr. | Denton, TX 76206 | Oil & Gas Operator | Mar 2002 |
| 267 | Hazelett Oil Company, Inc. | Dale, TX 78616 | Oil & Gas Operator | Sep 2005 |
| 268 | Hazelett Oil, Inc. | Dale, TX 78616 | Oil & Gas Operator | Aug 2024 |
| 269 | HB Oil Company | Abilene, TX 79602 | Oil & Gas Operator | Jun 2023 |
| 270 | HBC Oil Company, LLC | San Antonio, TX 78266 | Oil Operator | Apr 2025 |
| 271 | Hce Operating LLC | Smyer, TX 79367 | Oil & Gas Operator | Apr 2025 |
| 272 | HCM | Dallas, TX 75206 | Oil & Gas Operator | Mar 2015 |
| 273 | HD Special-Situations, LP | San Francisco, CA 94111 | Oil & Gas Operator | Feb 2014 |
| 274 | Headington Energy Corporation | Dallas, TX 75231 | Oil & Gas Operator | Aug 1992 |
| 275 | Headington Energy Partners, LLC | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Apr 2025 |
| 276 | Headington Oil Company | Dallas, TX 75231 | Oil & Gas Operator | Dec 2016 |
| 277 | Headington Oil Company LLC | Dallas, TX 75204 | Oil & Gas Operator | Apr 2016 |
| 278 | Headington Oil Company, L.P. | Dallas, TX 75231 | Oil & Gas Operator | Mar 2008 |
| 279 | Headline Resources, Inc. | Richardson, TX 75080 | Oil & Gas Operator | Aug 1997 |
| 280 | Headwaters Energy Partners, LLC | Dripping SPGS, TX 78620 | Oil & Gas Operator | Apr 2025 |
| 281 | Heape Exploration, Inc. | Dallas, TX 75367 | Oil & Gas Operator | Dec 2020 |
| 282 | Heape, Gene G. | Dallas, TX 75367 | Oil & Gas Operator | Jun 2003 |
| 283 | Heart Land Petroleum Corporation | Abilene, TX 79604 | Oil & Gas Operator | Mar 2008 |
| 284 | Heartland Production, Inc. | Cuero, TX 77954 | Oil & Gas Operator | Apr 2025 |
| 285 | Heartland Resources, Inc. | Temple, TX 76501 | Oil & Gas Operator | Mar 2008 |
| 286 | Hebron Energy, LLC | Dallas, TX 75206 | Oil Operator | Jul 2018 |
| 287 | Hec Petroleum, Inc | Midland, TX 79705 | Oil & Gas Operator | Mar 2006 |
| 288 | Hedrick Production Inc. | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Apr 2025 |
| 289 | Heflin, Bryan Exploration, Inc. | Strawn, TX 76475 | Oil & Gas Operator | Mar 2008 |
| 290 | Heifer Production Company LLC | Austin, TX 78746 | Oil & Gas Operator | Apr 2025 |
| 291 | Heights Energy Corporation | Plano, TX 75026 | Oil & Gas Operator | Apr 2025 |
| 292 | Heinrich Production Co Inc | Lubbuck, TX 79424 | Oil Operator | Dec 2024 |
| 293 | Heisey Ventures, Inc. | Houston, TX 77019 | Oil & Gas Operator | Apr 2025 |
| 294 | Held By Production, Inc. | Houston, TX 77251 | Oil & Gas Operator | May 1996 |
| 295 | Helios Operating, LLC | Houston, TX 77056 | Oil & Gas Operator | Apr 2025 |
| 296 | Helis Oil & Gas Company, L.L.C. | New Orleans, LA 70130 | Oil & Gas Operator | Oct 2023 |
| 297 | Helis, William G. Co., LLC, The | New Orleans, LA 70130 | Oil & Gas Operator | Oct 2003 |
| 298 | Helis,WM.G.,Est., A Partnership | New Orleans, LA 70130 | Oil & Gas Operator | Aug 2003 |
| 299 | Hellifino Operating, LLC | San Antonio, TX 78212 | Oil Operator | Apr 2025 |
| 300 | Hellums, Harold | Cedar Creek, TX 78612 | Oil & Gas Operator | Mar 2008 |