| 201 | Forest Oil Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 202 | Forza Operating, LLC | The Woodlands, TX 77380 | Oil & Gas Operator | May 2025 |
| 203 | Foundation Energy Management, LLC | Addison, TX 75001 | Oil & Gas Operator | May 2025 |
| 204 | Fowler Oil & Gas LLC | Fort Worth, TX 76109 | Oil & Gas Operator | May 2025 |
| 205 | Frazier Resources Company | Houston, TX 77057 | Gas Operator | May 2004 |
| 206 | Fredco | Louise, TX 77455 | Oil & Gas Operator | May 2025 |
| 207 | Fredonia Resources Inc. | Longview, TX 75606 | Oil & Gas Operator | Aug 2003 |
| 208 | Frio Exploration Company | Pearland, TX 77588 | Oil & Gas Operator | Dec 2000 |
| 209 | G E Operating, Inc. | Graham, TX 76450 | Oil & Gas Operator | May 2020 |
| 210 | Gaither Petroleum Corporation | Katy, TX 77493 | Oil & Gas Operator | May 2025 |
| 211 | Gardner Energy Corporation | Houston, TX 77024 | Oil & Gas Operator | Mar 1999 |
| 212 | Garrison LTD. | San Antonio, TX 78257 | Oil & Gas Operator | May 2025 |
| 213 | Gary Oil & Gas | Deer Park, TX 77536 | Oil & Gas Operator | May 2025 |
| 214 | Gasper Rice Resources, LTD. | Houston, TX 77068 | Oil & Gas Operator | May 2025 |
| 215 | Gcea, LLC | Graham, TX 76450 | Oil & Gas Operator | Mar 2008 |
| 216 | Gda Investments Inc | Oklahoma City, OK 73123-0403 | Oil & Gas Operator | Mar 2025 |
| 217 | Geiser Operating, Inc. | Portland, TX 78374 | Oil & Gas Operator | Sep 2019 |
| 218 | Geodominion Petroleum | Corpus Chrsti, TX 78403 | Oil & Gas Operator | May 2012 |
| 219 | Geonatural Resources, Inc. | Dallas, TX 75240 | Oil & Gas Operator | May 2025 |
| 220 | Geosouthern Energy Corporation | The Woodlands, TX 77380 | Oil & Gas Operator | May 2025 |
| 221 | Geosouthern Operating II, LLC | The Woodlands, TX 77380 | Oil & Gas Operator | May 2025 |
| 222 | Go-Energy Co. | San Antonio, TX 78232 | Oil & Gas Operator | Mar 2002 |
| 223 | Goodrich Exploration, L.L.C. | Houston, TX 77251 | Oil & Gas Operator | Sep 2005 |
| 224 | Goodrich Operating Company, Inc. | Houston, TX 77002 | Oil & Gas Operator | Mar 2006 |
| 225 | Graham Royalty LTD | Covington, LA 70434 | Oil & Gas Operator | Jul 2007 |
| 226 | Great Texas Crude Inc. | Fredericksbrg, TX 78624 | Oil & Gas Operator | May 2025 |
| 227 | Greenstone Energy, LLC | Houston, TX 77208 | Oil Operator | May 2025 |
| 228 | Gribble Oil Corporation | Dallas, TX 75235 | Oil Operator | Aug 1994 |
| 229 | Gruy Petroleum Management Co. | Irving, TX 75014 | Oil & Gas Operator | Nov 2014 |
| 230 | Guest Petroleum Incorporated | Edmond, OK 73013 | Oil & Gas Operator | Mar 2025 |
| 231 | Gulf States Production Company | Houston, TX 77027 | Oil & Gas Operator | Aug 1997 |
| 232 | Gulfstar Properties, Inc. | San Antonio, TX 78229 | Oil & Gas Operator | May 2025 |
| 233 | H & P Exploration Co. | Alice, TX 78333 | Oil & Gas Operator | May 2019 |
| 234 | H Oil Company, Inc. | Edna, TX 77957 | Oil & Gas Operator | Mar 2005 |
| 235 | Halbouty, Michel T. | Houston, TX 77056 | Oil & Gas Operator | Aug 1997 |
| 236 | Hallwood Petroleum, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jan 2025 |
| 237 | Hankamer, Curtis Corporation,The | Houston, TX 77024 | Oil & Gas Operator | May 2025 |
| 238 | Hanson Minerals Co. | Houston, TX 77042 | Oil & Gas Operator | Oct 1993 |
| 239 | Hanson Production Company | Cuero, TX 77954 | Oil & Gas Operator | Jul 2009 |
| 240 | Harken Exploration Company | Houston, TX 77079 | Oil & Gas Operator | Mar 2008 |
| 241 | Harrigan Energy Partners, Inc. | Houston, TX 77058 | Oil & Gas Operator | Sep 2010 |
| 242 | Harvest Petroleum Inc. | Frisco, TX 75033 | Oil & Gas Operator | May 2025 |
| 243 | Harwood Exploration, Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Aug 1995 |
| 244 | Hazelett Oil Company, Inc. | Dale, TX 78616 | Oil & Gas Operator | Sep 2005 |
| 245 | Hec Petroleum, Inc | Midland, TX 79705 | Oil & Gas Operator | Mar 2006 |
| 246 | Hess Corporation | Houston, TX 77010 | Oil & Gas Operator | Aug 2017 |
| 247 | Hibernia Resources, LLC | Houston, TX 77027 | Oil & Gas Operator | Jun 2014 |
| 248 | High Bluff Operating, LLC | Littleton, CO 80161 | Oil & Gas Operator | May 2018 |
| 249 | Hilcorp Energy Company | Houston, TX 77208 | Oil & Gas Operator | May 2025 |
| 250 | Hodge T F | Fort Worth, TX 76102 | Oil & Gas Operator | Apr 2007 |
| 251 | Hollimon Oil Corporation | Castroville, TX 78009 | Oil & Gas Operator | Nov 2016 |
| 252 | Home Petroleum Corp | Victoria, TX 77902 | Oil & Gas Operator | May 2025 |
| 253 | Horizon Exploration Company | Houston, TX 77019 | Oil & Gas Operator | Aug 2002 |
| 254 | Horizon Prod. And Operating, LLC | Houston, TX 77019 | Oil & Gas Operator | May 2025 |
| 255 | Hou-Tex, Inc. | Houston, TX 77224 | Oil & Gas Operator | Jun 2001 |
| 256 | Houston Gulf Energy Corporation | The Woodlands, TX 77380 | Oil & Gas Operator | May 2025 |
| 257 | Houston Operating, Inc. | Houston, TX 77027 | Oil & Gas Operator | May 2025 |
| 258 | Howard Exploration, Inc. | Houston, TX 77069 | Oil & Gas Operator | May 2025 |
| 259 | Howard, Douglas J. | Houston, TX 77070 | Oil & Gas Operator | Mar 2008 |
| 260 | Howell Drilling, Inc. | San Antonio, TX 78230 | Oil & Gas Operator | Aug 2003 |
| 261 | Hughes, Dan A. Company | Beeville, TX 78104 | Oil & Gas Operator | May 2006 |
| 262 | Hugoton Operating Company, Inc. | Dallas, TX 75240 | Oil & Gas Operator | May 2025 |
| 263 | Hunt Oil Company | Dallas, TX 75201 | Oil & Gas Operator | May 2025 |
| 264 | Hunt Petroleum (Aec), Inc. | Dallas, TX 75201 | Oil & Gas Operator | Nov 2008 |
| 265 | Hunt, WM. Herbert, Trust Est. | Dallas, TX 75201 | Oil & Gas Operator | Sep 1998 |
| 266 | Hurd Enterprises, LTD. | San Antonio, TX 78209 | Oil & Gas Operator | May 2025 |
| 267 | Hydrocarbon Horizons, Inc. | Corpus Chrsti, TX 78473 | Oil & Gas Operator | Jun 2023 |
| 268 | Hydrocarbon Operating, Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | May 2025 |
| 269 | Hyquest Energy, Inc. | Midland, TX 79710 | Oil & Gas Operator | Mar 2015 |
| 270 | Imperial Oil Company | Houston, TX 77073 | Oil & Gas Operator | Oct 2004 |
| 271 | Indexgeo & Associates, Inc. | Houston, TX 77002 | Oil & Gas Operator | Apr 2009 |
| 272 | Inexco Oil Company | Houston, TX 77210 | Oil & Gas Operator | Mar 2013 |
| 273 | Inland Ocean, Inc. | San Antonio, TX 78205 | Oil & Gas Operator | May 2025 |
| 274 | Integrated Operating Corporation | Dallas, TX 75243 | Oil & Gas Operator | May 2025 |
| 275 | Ip Petroleum Company, Inc. | Houston, TX 77210 | Oil & Gas Operator | Mar 2008 |
| 276 | Ipact | Austin, TX 78734 | Oil & Gas Operator | May 2025 |
| 277 | Iwr Operating, LLC | Dallas, TX 75248 | Oil Operator | May 2025 |
| 278 | J.R. Oil And Gas Inc. | Alvin, TX 77511 | Oil & Gas Operator | May 2025 |
| 279 | Jackson Energy Development, Inc. | Cedar Park, TX 78613 | Oil & Gas Operator | May 2025 |
| 280 | Jackson Petroleum Consulting,Inc | Plano, TX 75075 | Oil & Gas Operator | Sep 2019 |
| 281 | Jamex, Inc. | Lewisville, TX 75067 | Oil & Gas Operator | May 2025 |
| 282 | Jennings Exploration Company | Beeville, TX 78102 | Oil & Gas Operator | Feb 2024 |
| 283 | JN Exploration & Production LP | Billings, MT 59103 | Oil & Gas Operator | Jan 2001 |
| 284 | Johnson & Ernst Operating Co. | Wichita Falls, TX 76307 | Oil & Gas Operator | Sep 2018 |
| 285 | Jones, Edwin M. Oil Co. | Fort Worth, TX 76102 | Oil & Gas Operator | May 2025 |
| 286 | Josey, Lenoir M., Inc. | Houston, TX 77019 | Oil & Gas Operator | Aug 2003 |
| 287 | Jud,L.C. | Corpus Chrsti, TX 78473 | Gas Operator | Jul 2003 |
| 288 | K-B Exploration Co. | Houston, TX 77057 | Oil & Gas Operator | May 2025 |
| 289 | Kaiser-Francis Oil Company | Tulsa, OK 74121 | Oil & Gas Operator | May 2025 |
| 290 | Kaler Energy Corp. | Boerne, TX 78006 | Oil & Gas Operator | May 2025 |
| 291 | Karis Resources, LLC | Tyler, TX 75707 | Oil & Gas Operator | Feb 2019 |
| 292 | Karper Company, The | Graham, TX 76450 | Oil & Gas Operator | Feb 2003 |
| 293 | Karper Oil & Gas Corporation | Graham, TX 76450 | Oil & Gas Operator | May 2025 |
| 294 | KCS Resources, Inc. | Houston, TX 77002 | Oil & Gas Operator | Feb 2009 |
| 295 | Kebo Oil & Gas, Inc. | Portland, TX 78374 | Oil & Gas Operator | May 2025 |
| 296 | Kelso Oil LLC | Chase, KS 67524 | Oil & Gas Operator | Apr 2007 |
| 297 | Ken Petroleum Corporation | Dallas, TX 75206 | Oil & Gas Operator | Feb 2019 |
| 298 | Kenne Exploration, Inc. | Missouri City, TX 77489 | Oil & Gas Operator | May 2025 |
| 299 | Kerns O & G, Inc. | San Antonio, TX 78232 | Oil & Gas Operator | Dec 2004 |
| 300 | Kerns Petroleum, Inc. | San Antonio, TX 78257 | Oil & Gas Operator | Sep 2013 |