| 301 | Paramount Producing, Inc. | Pampa, TX 79066 | Oil & Gas Operator | Oct 1996 |
| 302 | Parker & Parsley Development Co. | Midland, TX 79702 | Oil & Gas Operator | May 1995 |
| 303 | Parker & Parsley Development L.P | Midland, TX 79702 | Oil & Gas Operator | Oct 2007 |
| 304 | Parker & Parsley Producing LP | Midland, TX 79702 | Oil & Gas Operator | Oct 1997 |
| 305 | Patrick & Vaughn | Oklahoma City, OK 73154 | Oil & Gas Operator | Sep 2005 |
| 306 | Payne, W. C. | Nichols Hill, OK 73116 | Oil & Gas Operator | Sep 2005 |
| 307 | Peak Texas Resources, LLC | Durango, CO 81301 | Oil & Gas Operator | Mar 2017 |
| 308 | Pennzenergy Exp. & Prod., L.L.C. | Houston, TX 77210 | Oil & Gas Operator | Mar 2000 |
| 309 | Pennzoil Exploration & Production Co. | Carthage, TX 75633 | Oil & Gas Operator | Mar 2008 |
| 310 | Pennzoil Petroleum Company | Houston, TX 77252 | Oil & Gas Operator | Nov 1999 |
| 311 | Petro-Haley | Borger, TX 79008 | Oil & Gas Operator | Jul 2025 |
| 312 | Petro-Smith Operating LLC | Houston, TX 77010 | Oil & Gas Operator | Jul 2025 |
| 313 | Petroleum Inc | Wichita, KS 67202 | Oil & Gas Operator | Oct 2021 |
| 314 | PG-M International Operating,LLC | Borger, TX 79008 | Oil & Gas Operator | Jul 2025 |
| 315 | Philcon Development Co. | Amarillo, TX 79101 | Oil & Gas Operator | Sep 2014 |
| 316 | Phillips Petroleum Company | Houston, TX 77251 | Oil & Gas Operator | Mar 2013 |
| 317 | Pioneer Natural Res. USA, Inc. | Spring, TX 77389 | Oil & Gas Operator | Jul 2025 |
| 318 | Pioneer Resources Producing, L.P | Irving, TX 75039 | Oil & Gas Operator | Feb 2001 |
| 319 | Plains Exploration & Prod. Co. | Houston, TX 77002 | Oil & Gas Operator | Jul 2013 |
| 320 | Plains Marketing, LP | Cushing, OK 74023 | Oil Operator | Jan 2012 |
| 321 | Plains Production Inc | Wichita Falls, TX 76308 | Oil & Gas Operator | Dec 1995 |
| 322 | Pogo Panhandle 2004, L.P. | Houston, TX 77002 | Oil & Gas Operator | Oct 2017 |
| 323 | Pogo Producing Company LLC | Houston, TX 77002 | Oil & Gas Operator | May 2025 |
| 324 | Presidio Petroleum LLC | Canadian, TX 79014 | Oil & Gas Operator | Jul 2025 |
| 325 | Princess Three Corporation | Henderson, TX 75653 | Oil & Gas Operator | Apr 2020 |
| 326 | Prize Operating Company | Grapevine, TX 76051 | Oil & Gas Operator | Aug 2016 |
| 327 | Producers Operating Co Inc | Amarillo, TX 79105 | Oil & Gas Operator | Jul 2025 |
| 328 | Proven Reserves Management, Inc. | Dallas, TX 75370 | Oil & Gas Operator | Apr 2025 |
| 329 | PXP Gulf Coast Inc. | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 330 | Qep Energy Company | Midland, TX 79701 | Oil & Gas Operator | Apr 2025 |
| 331 | Quanah Panhandle, LLC | Traverse City, MI 49684 | Oil & Gas Operator | Jul 2025 |
| 332 | Quantum Resources Management LLC | Houston, TX 77010 | Oil & Gas Operator | Apr 2025 |
| 333 | Questa Energy Corporation | Amarillo, TX 79159 | Oil & Gas Operator | Jul 2025 |
| 334 | Questa Operating Company, LLC | Amarillo, TX 79159 | Oil & Gas Operator | Jul 2025 |
| 335 | Questar Expl. And Prod. Co. | Salt Lake Cty, UT 84145 | Oil & Gas Operator | Jul 2011 |
| 336 | R & A Moore, Inc. | Cleburne, TX 76033 | Oil & Gas Operator | Jul 2025 |
| 337 | R.E.D. Resources, Inc. | Perryton, TX 79070 | Oil & Gas Operator | Apr 2004 |
| 338 | Ram Operating Inc. | Browns, IL 62818 | Oil & Gas Operator | Aug 2008 |
| 339 | Ramco Oil & Gas Inc | Midland, TX 79701 | Oil & Gas Operator | Nov 2006 |
| 340 | Ramco Operating Company | Tulsa, OK 74135 | Oil & Gas Operator | Jan 1998 |
| 341 | Range Production Company | Fort Worth, TX 76102 | Oil & Gas Operator | Sep 2021 |
| 342 | Range Production Company, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Apr 2025 |
| 343 | Ranken Energy Corporation | Edmond, OK 73013 | Oil & Gas Operator | Apr 2025 |
| 344 | Raydon Exploration, Inc. | Oklahoma City, OK 73118 | Oil & Gas Operator | Jul 2025 |
| 345 | Regent Oil & Gas Company, L.P. | Dallas, TX 75225 | Oil & Gas Operator | Sep 2006 |
| 346 | Remnant Energy, Inc. | Perryton, TX 79070 | Oil & Gas Operator | Jul 2025 |
| 347 | Revolution Operating Company,LLC | Oklahoma City, OK 73134 | Oil & Gas Operator | Jul 2024 |
| 348 | Riata Energy Inc | Oklahoma City, OK 73101 | Oil & Gas Operator | Apr 2008 |
| 349 | Ricks Exploration, Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Mar 2008 |
| 350 | Rig Petroleum, LLC | Spearman, TX 79081 | Oil & Gas Operator | Jul 2025 |
| 351 | Rim Operating, Inc. | Englewood, CO 80112 | Oil & Gas Operator | Jul 2025 |
| 352 | Rio Petroleum, Inc. | Amarillo, TX 79102 | Oil & Gas Operator | Jul 2025 |
| 353 | Rockford Panhandle, LLC | Tulsa, OK 74105 | Oil & Gas Operator | Sep 2008 |
| 354 | Roemer Oil Company | Denver, CO 80202 | Oil & Gas Operator | Nov 1998 |
| 355 | Rosetta Resources Operating LP | San Antonio, TX 78216 | Oil & Gas Operator | Jul 2025 |
| 356 | RTC Resources, LLP | Weatherford, OK 73096 | Oil & Gas Operator | Jul 2025 |
| 357 | RTD Inc | Bartlesville, OK 74006 | Oil Operator | Jan 1995 |
| 358 | RW Operating Corp. | Midland, TX 79702 | Oil & Gas Operator | Jul 2016 |
| 359 | Sabre Operating, Inc. | Wichita Falls, TX 76308 | Oil & Gas Operator | Jul 2025 |
| 360 | Saguaro Petroleum, LLC | Midland, TX 79705 | Oil & Gas Operator | Jul 2025 |
| 361 | Samson Hydrocarbons Company | Tulsa, OK 74103 | Oil & Gas Operator | Nov 2016 |
| 362 | Samson Lone Star LP | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2007 |
| 363 | Samson Lone Star, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Jul 2025 |
| 364 | Samson Resources Company | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2025 |
| 365 | San Marco Petroleum Inc | Denver, CO 80293 | Oil & Gas Operator | Jun 2025 |
| 366 | Sand Springs Oil & Gas Co. | Tulsa, OK 74136 | Oil & Gas Operator | Jul 2025 |
| 367 | Sandia Operating Corp. | San Antonio, TX 78270 | Oil & Gas Operator | May 2010 |
| 368 | Sandlot Oil & Gas LLC | Gruver, TX 79040 | Oil & Gas Operator | Jul 2025 |
| 369 | Santa Fe Energy Oper. Part., LP | Houston, TX 77057 | Oil & Gas Operator | Dec 1994 |
| 370 | Sapient Energy Corp | Oklahoma City, OK 73154 | Oil & Gas Operator | Jan 2002 |
| 371 | Scout Energy Management LLC | Dallas, TX 75240 | Oil & Gas Operator | Jul 2025 |
| 372 | SCS Newton Oil LLC | Perryton, TX 79070 | Oil & Gas Operator | Jul 2025 |
| 373 | Service Drilling Co. | Tulsa, OK 74119 | Oil & Gas Operator | Oct 1998 |
| 374 | Sheridan Energy,Inc. | Houston, TX 77002 | Oil & Gas Operator | Feb 2000 |
| 375 | Shidler, Mark L., Inc. | Houston, TX 77055 | Oil & Gas Operator | Jul 2025 |
| 376 | Sidwell Oil & Gas, Inc. | Amarillo, TX 79105 | Oil & Gas Operator | Sep 2014 |
| 377 | Sidwell Operating Company, L.P. | Amarillo, TX 79105 | Oil & Gas Operator | Jul 2025 |
| 378 | Skinnergy Co. | Spearman, TX 79081 | Oil & Gas Operator | Jul 2025 |
| 379 | Smith Operating And MGMT Co. | Shreveport, LA 71161 | Oil & Gas Operator | Jun 2023 |
| 380 | SNW Operating Company | Borger, TX 79008 | Oil & Gas Operator | Jul 2025 |
| 381 | Sonat Exploration Company-MCR | Houston, TX 77251 | Oil & Gas Operator | Dec 1999 |
| 382 | Southcross Operating LLC | Amarillo, TX 79114 | Oil & Gas Operator | Oct 2005 |
| 383 | Southwestern Energy Prod Co | Houston, TX 77032 | Oil & Gas Operator | Jun 2015 |
| 384 | Speartex Grain Company | Gruver, TX 79040 | Oil & Gas Operator | Jul 2025 |
| 385 | Speller Oil Corporation | Oklahoma City, OK 73112 | Oil & Gas Operator | Apr 2025 |
| 386 | Spicknall Enterprises | Amarillo, TX 79124 | Oil & Gas Operator | May 1998 |
| 387 | Spring Resources, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Jul 2007 |
| 388 | Stahl Petroleum Co. | Amarillo, TX 79118 | Oil & Gas Operator | Aug 2003 |
| 389 | Stallion Energy LLC | Houston, TX 77090 | Oil & Gas Operator | Oct 2009 |
| 390 | Stallion Energy, Inc. | Houston, TX 77060 | Oil & Gas Operator | Oct 2017 |
| 391 | Starr Operating Company | Austin, TX 78759 | Oil & Gas Operator | Jul 2025 |
| 392 | Strat Land Exploration Company | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2025 |
| 393 | Sullivan & Co. | Tulsa, OK 74114 | Oil & Gas Operator | May 2022 |
| 394 | Sundown Energy, Inc. | Dallas, TX 75240 | Oil & Gas Operator | Mar 2025 |
| 395 | Sunlight Exploration, Inc. | Canyon, TX 79015 | Oil & Gas Operator | Jul 2025 |
| 396 | Suoco Oil Corporation | Pampa, TX 79066 | Oil & Gas Operator | Jul 2025 |
| 397 | Sutherland Energy Co., LLC | Bridgeport, TX 76426 | Oil & Gas Operator | Jul 2025 |
| 398 | T-Y Development Corp | Perryton, TX 79070 | Oil & Gas Operator | Jul 2025 |
| 399 | Tamarack Petroleum Company, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jul 2025 |
| 400 | Taylor Energy Corporation | Amarillo, TX 79114 | Oil & Gas Operator | Feb 1999 |