| 201 | Scully And Smith Oil Corporation | Salado, TX 76571 | Oil & Gas Operator | Feb 1995 |
| 202 | Seay Oil & Gas, LTD. | Dripping SPGS, TX 78620 | Oil & Gas Operator | Apr 2013 |
| 203 | Sellers Lease Service, Inc. | Flatonia, TX 78941 | Oil & Gas Operator | Dec 2025 |
| 204 | Shale Operating Co. | Dallas, TX 75356 | Oil & Gas Operator | Dec 2025 |
| 205 | Shefts & Shefts, Inc. | Luling, TX 78648 | Oil & Gas Operator | Dec 2025 |
| 206 | Sheldon Resources, L.P. | Bryan, TX 77805 | Oil & Gas Operator | Dec 2025 |
| 207 | Shidler, Mark L., Inc. | Houston, TX 77055 | Oil & Gas Operator | Dec 2025 |
| 208 | Shield Petroleum | College Sta, TX 77845 | Oil & Gas Operator | Dec 2025 |
| 209 | Sierra Minerals, Inc. | Rockdale, TX 76567 | Oil & Gas Operator | Dec 2025 |
| 210 | Skytop Oil & Gas | Giddings, TX 78942 | Oil & Gas Operator | Dec 2025 |
| 211 | Smith, L C Production | Jacksonville, TX 75766 | Oil Operator | Dec 2025 |
| 212 | Somont Oil Co., Inc. | Spring, TX 77379 | Oil & Gas Operator | Nov 2025 |
| 213 | Sonoble Operating, Inc. | Dallas, TX 75240 | Oil & Gas Operator | Jun 2003 |
| 214 | South Texas Drilling & Expl, Inc | San Antonio, TX 78217 | Oil & Gas Operator | Jan 1999 |
| 215 | Southridge Operating Company | San Marcos, TX 78667 | Oil & Gas Operator | Dec 2025 |
| 216 | Spiller, J.A. | Austin, TX 78735 | Oil & Gas Operator | Jan 2016 |
| 217 | Spiller, Joseph A. | Austin, TX 78746 | Oil & Gas Operator | Oct 1993 |
| 218 | Stanton Mineral Development Inc | Austin, TX 78759 | Oil & Gas Operator | Dec 2025 |
| 219 | Sto Operating Company | San Antonio, TX 78258 | Oil & Gas Operator | Dec 2025 |
| 220 | Stratco Operating Co Inc | Austin, TX 78701 | Oil & Gas Operator | Dec 2025 |
| 221 | T.D. Operating Company, Inc. | New Braunfels, TX 78130 | Oil & Gas Operator | Nov 1999 |
| 222 | Tanglewood Oil & Gas Co. | Gouldbusk, TX 76845 | Oil & Gas Operator | Dec 2025 |
| 223 | Taylor, Ben J. Inc. | Fort Worth, TX 76185 | Oil & Gas Operator | Feb 2022 |
| 224 | TDC Engineering, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Dec 2025 |
| 225 | Tejones Operating Corporation | San Antonio, TX 78217 | Oil & Gas Operator | Dec 2025 |
| 226 | Tekna Synergy Corporation | Midland, TX 79702 | Oil & Gas Operator | Dec 2025 |
| 227 | Terrafina Energy, LLC | San Antonio, TX 78280 | Oil & Gas Operator | Dec 2025 |
| 228 | Tex-Lee Operating Company | Giddings, TX 78942 | Oil & Gas Operator | Dec 2025 |
| 229 | Texakoma Oil & Gas Corp | Dallas, TX 75240 | Oil & Gas Operator | Sep 2014 |
| 230 | Texana Operating Company | Houston, TX 77090 | Oil & Gas Operator | Dec 2025 |
| 231 | Texas Refining, Inc. | Houston, TX 77057 | Oil & Gas Operator | Aug 2003 |
| 232 | Texas Vanguard Oil Company | Austin, TX 78720 | Oil & Gas Operator | Jan 2014 |
| 233 | Texas-Ohio Producing Company | Spring, TX 77383 | Oil & Gas Operator | Jul 1995 |
| 234 | Thomas Oil & Gas Company | Luling, TX 78648 | Oil & Gas Operator | Aug 2003 |
| 235 | Thrall Operating Company, Inc. | Dallas, TX 75240 | Oil & Gas Operator | Dec 2025 |
| 236 | Three Forks Operating Co, LLC | Flatonia, TX 78941 | Oil & Gas Operator | Dec 2025 |
| 237 | Torch Operating Company | Houston, TX 77010 | Oil & Gas Operator | Mar 2015 |
| 238 | Tortuga Operating Company | Houston, TX 77055 | Oil & Gas Operator | Dec 2025 |
| 239 | Tracer Energy, Inc. | Graham, TX 76450 | Oil & Gas Operator | Nov 1998 |
| 240 | Tri-C Resources, Inc. | Houston, TX 77024 | Oil & Gas Operator | Aug 2009 |
| 241 | Triad Energy Corporation | Houston, TX 77057 | Oil & Gas Operator | Oct 2011 |
| 242 | Trinidad Petroleum, Inc. | Austin, TX 78711 | Oil & Gas Operator | Dec 2025 |
| 243 | Triple C Oil Inc. | Lockhart, TX 78644 | Oil Operator | Aug 2019 |
| 244 | Triple J Investments Inc | Longview, TX 75606 | Oil & Gas Operator | Feb 2023 |
| 245 | Trivista Operating LLC | Giddings, TX 78942 | Oil & Gas Operator | Dec 2025 |
| 246 | Tuskar (Texas), Inc. | Nichols Hill, OK 73116 | Oil & Gas Operator | Jan 2016 |
| 247 | Union Oil Co Of California | Midland, TX 79706 | Oil & Gas Operator | Jan 2022 |
| 248 | Union Pacific Resources Co. | Fort Worth, TX 76101 | Oil & Gas Operator | Jan 2001 |
| 249 | United Operating, LLC *** | Midland, TX 79710 | Oil & Gas Operator | Dec 2025 |
| 250 | Ursa Operating Company LLC | Denver, CO 80265 | Oil & Gas Operator | Feb 2014 |
| 251 | USA Superior Energy LLC | Houston, TX 77077 | Oil Operator | Mar 2010 |
| 252 | Valentine Oil & Gas, L.C. | Carmine, TX 78932 | Oil Operator | Nov 2018 |
| 253 | Viceroy Petroleum GP, LLC | Rockdale, TX 76567 | Oil & Gas Operator | Feb 2010 |
| 254 | Viceroy Petroleum, LP | College Sta, TX 77845 | Oil & Gas Operator | Dec 2025 |
| 255 | Viva Petrol LLP | Pflugerville, TX 78660 | Oil Operator | Dec 2025 |
| 256 | Voskamp Exploration, Inc. | Midland, TX 79708 | Oil & Gas Operator | Sep 2010 |
| 257 | Wainoco Oil & Gas Company | Houston, TX 77024 | Oil & Gas Operator | Dec 2005 |
| 258 | Wallis Energy, Inc. | Austin, TX 78746 | Oil & Gas Operator | Dec 2025 |
| 259 | Warrior Resources Inc. | Mexia, TX 76667 | Oil & Gas Operator | Dec 2025 |
| 260 | WCS Oil & Gas Corporation | Dallas, TX 75209 | Oil & Gas Operator | Aug 2021 |
| 261 | Weber Energy Corporation | Dallas, TX 75219 | Oil & Gas Operator | Feb 2017 |
| 262 | Wildfire Energy Operating LLC | Houston, TX 77224 | Oil & Gas Operator | Dec 2025 |
| 263 | Wildhorse Resources MNGT Co, LLC | Oklahoma City, OK 73154 | Oil & Gas Operator | May 2019 |
| 264 | Williams, Clayton Energy, Inc. | Houston, TX 77070 | Oil & Gas Operator | Dec 2025 |
| 265 | Wilson Hydrocarbon Inc. | Houston, TX 77066 | Oil & Gas Operator | Dec 2025 |
| 266 | Wise Star Energy, LLC | Port Aransas, TX 78373 | Oil & Gas Operator | Dec 2025 |
| 267 | Xenon Energy, Inc. | Plano, TX 75074 | Oil & Gas Operator | Aug 2003 |
| 268 | Xophi Energy, LLC | Arlington, TX 76006 | Oil & Gas Operator | Dec 2025 |
| 269 | Zavala Independent Gas, Inc. | San Antonio, TX 78217 | Oil & Gas Operator | Oct 2007 |
| 270 | Zinn Petroleum Co. | Houston, TX 77024 | Oil & Gas Operator | Nov 2021 |