| 201 | Rodessa Operating Company | Corpus Chrsti, TX 78426 | Oil & Gas Operator | Jul 2025 |
| 202 | Roosth Production Co. | Tyler, TX 75711 | Oil & Gas Operator | Jul 2025 |
| 203 | Rosetta Resources Operating LP | San Antonio, TX 78216 | Oil & Gas Operator | Jul 2025 |
| 204 | Rotation, Incorporated | Houston, TX 77057 | Oil & Gas Operator | Mar 2023 |
| 205 | Royalty Land & Dev. Co., Inc. | Wolfforth, TX 79382 | Oil & Gas Operator | Jul 2025 |
| 206 | Royalty Resources, L.L.C. | Midland, TX 79702 | Oil & Gas Operator | Jul 2025 |
| 207 | Rusk Energy Operating LLC | Houston, TX 77040 | Oil & Gas Operator | Jul 2025 |
| 208 | S & Y Production Co. | Liberty, TX 77575 | Oil & Gas Operator | Jul 1996 |
| 209 | Sage Energy Company | San Antonio, TX 78215 | Oil & Gas Operator | Jul 2025 |
| 210 | Samson Hydrocarbons Company | Tulsa, OK 74103 | Oil & Gas Operator | Nov 2016 |
| 211 | Samson Lone Star LP | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2007 |
| 212 | Samson Lone Star, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Jul 2025 |
| 213 | Samson Resources Company | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2025 |
| 214 | Sanchez Oil & Gas Corporation | Houston, TX 77056 | Oil & Gas Operator | Jul 2025 |
| 215 | Sanchez-O'Brien Oil & Gas Corp | Houston, TX 77057 | Oil & Gas Operator | May 1998 |
| 216 | Sandel Energy, Inc. | Huntsville, TX 77342 | Oil & Gas Operator | Apr 2004 |
| 217 | Sandel Operating Company | Huntsville, TX 77340 | Oil & Gas Operator | Jul 2025 |
| 218 | Sandhawk Energy, LLC | Houston, TX 77079 | Oil & Gas Operator | Jun 2011 |
| 219 | Schwab City Resources | Leggett, TX 77350 | Oil & Gas Operator | Aug 2013 |
| 220 | Sendero Energy Inc. | Dallas, TX 75205 | Oil & Gas Operator | Jul 2025 |
| 221 | Shale Oil Co., Inc. | Liberty, TX 77575 | Oil & Gas Operator | Jul 2025 |
| 222 | Shidler, Mark L., Inc. | Houston, TX 77055 | Oil & Gas Operator | Jul 2025 |
| 223 | SM Operating Company LLC | Houston, TX 77056 | Oil & Gas Operator | Jul 2025 |
| 224 | Smyth Oil Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2003 |
| 225 | Smyth Oil LLC | Houston, TX 77002 | Oil & Gas Operator | Jul 2025 |
| 226 | Sonat Exploration Company -Tyler | Houston, TX 77251 | Oil & Gas Operator | Dec 1999 |
| 227 | Southwest Oil & Land, Inc. | Corpus Chrsti, TX 78460 | Oil & Gas Operator | Dec 1999 |
| 228 | Square Mile Energy, L.L.C. | Houston, TX 77057 | Oil & Gas Operator | Jul 2025 |
| 229 | SSC, Inc. | Lubbock, TX 79408 | Oil & Gas Operator | Jul 2025 |
| 230 | Stanton Mineral Development Inc | Austin, TX 78759 | Oil & Gas Operator | Jul 2025 |
| 231 | Stone & Webster Oil Company, Inc | Houston, TX 77002 | Oil & Gas Operator | Dec 1995 |
| 232 | Stratco Operating Co Inc | Austin, TX 78701 | Oil & Gas Operator | Jul 2025 |
| 233 | Sue-Ann Operating, L.C. | Victoria, TX 77903 | Oil & Gas Operator | Jul 2025 |
| 234 | Summit Resources MGMT., LLC. | Edmond, OK 73083 | Oil & Gas Operator | Jul 2025 |
| 235 | Sundown Energy LP | Dallas, TX 75248 | Oil & Gas Operator | Jul 2025 |
| 236 | Synergy Oil & Gas, Inc. (A) | Houston, TX 77024 | Oil & Gas Operator | Aug 2001 |
| 237 | Synergy Production Company | Houston, TX 77024 | Oil & Gas Operator | Jan 1996 |
| 238 | Tap Operating Company, Inc. | Mexia, TX 76667 | Oil & Gas Operator | May 1995 |
| 239 | TC3 Energy Services Company | Bryan, TX 77805 | Oil & Gas Operator | Jan 2005 |
| 240 | Texaco E & P Inc | Houston, TX 77099 | Oil & Gas Operator | Jul 2025 |
| 241 | Texana Operating Company | Houston, TX 77090 | Oil & Gas Operator | Jul 2025 |
| 242 | Totalfinaelf E&P USA Inc | Houston, TX 77024 | Oil & Gas Operator | Jul 2007 |
| 243 | Transoil, Inc. | Oklahoma City, OK 73129 | Oil & Gas Operator | Jul 2025 |
| 244 | Umc Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 245 | Union Oil Co Of California | Midland, TX 79706 | Oil & Gas Operator | Jan 2022 |
| 246 | Union Pacific Resources Co. | Fort Worth, TX 76101 | Oil & Gas Operator | Sep 2002 |
| 247 | Unit Petroleum Company | Tulsa, OK 74170 | Oil & Gas Operator | Jul 2025 |
| 248 | Urban Oil & Gas Group, LLC | Plano, TX 75074 | Oil & Gas Operator | Jul 2025 |
| 249 | Ursa Operating Company LLC | Denver, CO 80265 | Oil & Gas Operator | Dec 2020 |
| 250 | Vanco Oil & Gas Corp. | Abilene, TX 79604 | Oil & Gas Operator | Jul 2025 |
| 251 | Vanya Oil & Gas, Inc. | Hardin, TX 77561 | Oil & Gas Operator | Jul 2025 |
| 252 | Ventex Operating Corp. | Addison, TX 75001 | Oil & Gas Operator | Jul 2025 |
| 253 | Viesca Gas Co. | Spring, TX 77379 | Oil & Gas Operator | Jul 2025 |
| 254 | Vision Energy LLC | Houston, TX 77002 | Oil & Gas Operator | May 2025 |
| 255 | Vision Operating Company, L.L.C. | Houston, TX 77027 | Oil & Gas Operator | Jul 2025 |
| 256 | Votaw Production Company LLC | Houston, TX 77007 | Oil Operator | Jul 2025 |
| 257 | Wainoco Oil & Gas Company | Houston, TX 77024 | Oil & Gas Operator | Dec 2005 |
| 258 | Walter Oil & Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Jul 2025 |
| 259 | Wapiti Operating, LLC | Houston, TX 77043 | Oil & Gas Operator | Jul 2025 |
| 260 | WCS Oil & Gas Corporation | Dallas, TX 75209 | Oil & Gas Operator | Aug 2021 |
| 261 | Westco Oil Company | Ozona, TX 76943 | Oil & Gas Operator | Jul 2025 |
| 262 | Whitehead Resources, LTD. | Buna, TX 77612 | Oil & Gas Operator | Jul 2025 |
| 263 | Whiting Petroleum Corporation | Denver, CO 80290 | Oil & Gas Operator | Jan 2025 |
| 264 | Wildhorse Resources, LLC | Houston, TX 77279 | Oil & Gas Operator | Feb 2015 |
| 265 | Willow Creek Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Feb 2009 |
| 266 | Wilson Oil Co. | Houston, TX 77263 | Oil & Gas Operator | Jul 2025 |
| 267 | XTO Energy Inc. | Spring, TX 77389 | Oil & Gas Operator | Jul 2025 |
| 268 | Yentzen Investments, Inc. | Sugar Land, TX 77478 | Oil Operator | May 1993 |
| 269 | Yuma E & P Company, Inc. | Houston, TX 77027 | Oil & Gas Operator | Jul 2025 |
| 270 | Zachry Exploration, LTD. | San Antonio, TX 78205 | Oil & Gas Operator | Jan 2009 |
| 271 | Zarvona Energy LLC | Houston, TX 77002 | Oil & Gas Operator | Jul 2025 |
| 272 | Zinke & Trumbo, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Mar 2007 |
| 273 | Zinn Petroleum Co. | Houston, TX 77024 | Oil & Gas Operator | Nov 2021 |