| 301 | MRR Oil Inc. | Perryton, TX 79070 | Oil & Gas Operator | Jun 2002 |
| 302 | Mustang Fuel Corp. Of Oklahoma | Oklahoma City, OK 73106 | Oil & Gas Operator | Nov 2016 |
| 303 | Myriad Resources Corporation | Pampa, TX 79066 | Oil & Gas Operator | Dec 2025 |
| 304 | Nadel & Gussman | Tulsa, OK 74103 | Oil & Gas Operator | May 2007 |
| 305 | Nadel And Gussman LLC | Tulsa, OK 74119 | Oil & Gas Operator | Dec 2025 |
| 306 | Natural Gas Anadarko Company | Perryton, TX 79070 | Oil & Gas Operator | Dec 2025 |
| 307 | New London Oil Inc. | Houston, TX 77253 | Oil & Gas Operator | Aug 2002 |
| 308 | Newfield Expl. Mid-Con. Inc | Tulsa, OK 74172 | Oil & Gas Operator | Jan 2015 |
| 309 | Newton Corp.,The | Dallas, TX 75251 | Oil & Gas Operator | Dec 2025 |
| 310 | Nielson & Associates, Inc | Cody, WY 82414 | Oil & Gas Operator | Feb 2016 |
| 311 | Nja Operating LLC | Perryton, TX 79070 | Oil & Gas Operator | Dec 2025 |
| 312 | Noble Energy Inc | Midland, TX 79706 | Oil & Gas Operator | Dec 2025 |
| 313 | Noble Energy Production Inc | Houston, TX 77067 | Oil & Gas Operator | Dec 2025 |
| 314 | Nomeco Oil & Gas Co. | Jackson, MI 49204 | Oil & Gas Operator | Dec 1994 |
| 315 | Okie Operating Company, LTD. | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2025 |
| 316 | Oklahoma Marlin Oil Corporation | Oklahoma City, OK 73113 | Oil & Gas Operator | Feb 2020 |
| 317 | Oklahoma RB Operating Company | Midland, TX 79701 | Oil & Gas Operator | Jan 1998 |
| 318 | Oklahoma Sterling Oil & Gas Corp | Tulsa, OK 74170 | Oil & Gas Operator | Jun 1997 |
| 319 | Oneok Exploration Company | Tulsa, OK 74102 | Oil & Gas Operator | Feb 2017 |
| 320 | Opal Operating Company LLC | Edmond, OK 73013 | Oil & Gas Operator | Dec 2025 |
| 321 | Oringderff, Alma Oil Properties | Dallas, TX 75225 | Oil & Gas Operator | Mar 2012 |
| 322 | Orion Oil & Gas Properties | Amarillo, TX 79109 | Gas Operator | Oct 2000 |
| 323 | Otc Petroleum Corporation | Nichols Hill, OK 73116 | Oil & Gas Operator | Mar 2015 |
| 324 | Overflow Energy, LLC | Perryton, TX 79070 | Oil & Gas Operator | Dec 2025 |
| 325 | Palace Exploration Company | Houston, TX 77002 | Oil & Gas Operator | Mar 2007 |
| 326 | Paleo, Inc. | Oklahoma City, OK 73112 | Oil & Gas Operator | Dec 2025 |
| 327 | Pan Western Energy Corporation | Tulsa, OK 74114 | Oil & Gas Operator | Dec 2025 |
| 328 | Panada Exploration, Inc. | Tulsa, OK 74135 | Oil & Gas Operator | Jun 1996 |
| 329 | Panda Pipe & Equipment, Inc. | Midland, TX 79702 | Oil & Gas Operator | Oct 1996 |
| 330 | Panhandle Oil & Gas Inc | Oklahoma City, OK 73112-5688 | Oil & Gas Operator | May 2007 |
| 331 | Pantera Energy Company | Amarillo, TX 79101 | Oil & Gas Operator | Dec 2025 |
| 332 | Paradis Investments, L.L.C. | Bellaire, TX 77401 | Oil Operator | Jun 2020 |
| 333 | Parker & Parsley Development Co. | Midland, TX 79702 | Oil & Gas Operator | May 1995 |
| 334 | Parker & Parsley Development L.P | Midland, TX 79702 | Oil & Gas Operator | Oct 2007 |
| 335 | Patina Oil & Gas Corporation | Denver, CO 80202 | Oil & Gas Operator | May 2016 |
| 336 | Peak Operating Of Texas, LLC | Denver, CO 80202 | Oil & Gas Operator | May 2005 |
| 337 | Peak Texas Resources, LLC | Durango, CO 81301 | Oil & Gas Operator | Mar 2017 |
| 338 | Pennzoil Petroleum Company | Houston, TX 77252 | Oil & Gas Operator | Nov 1999 |
| 339 | Perdure Petroleum LLC | Allen, TX 75013 | Oil & Gas Operator | Oct 2021 |
| 340 | Petco Energy Corporation | Hinsdale, IL 60521 | Oil & Gas Operator | Dec 2025 |
| 341 | Petco Petroleum Corp | Hinsdale, IL 60521 | Oil & Gas Operator | Sep 2025 |
| 342 | Petrohawk Operating Company | Houston, TX 77056 | Oil & Gas Operator | Oct 2021 |
| 343 | Petroleum Inc | Wichita, KS 67202 | Oil & Gas Operator | Oct 2021 |
| 344 | Petroleum Properties MGMT Co LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Aug 2005 |
| 345 | Petroleum Properties MGMT. Co. | Oklahoma City, OK 73118 | Oil & Gas Operator | Dec 2014 |
| 346 | Philcon Development Co. | Amarillo, TX 79101 | Oil & Gas Operator | Sep 2014 |
| 347 | Phillips Petroleum Company | Houston, TX 77251 | Oil & Gas Operator | Mar 2013 |
| 348 | Phoenix Hydrocarbons Operating | Midland, TX 79702 | Oil & Gas Operator | Jun 2024 |
| 349 | Pioneer Natural Res. USA, Inc. | Spring, TX 77389 | Oil & Gas Operator | Dec 2025 |
| 350 | Pitco Investments, LTD. | Scottsdale, AZ 85261 | Oil & Gas Operator | Jan 2013 |
| 351 | Plains Exploration & Prod. Co. | Houston, TX 77002 | Oil & Gas Operator | Jul 2013 |
| 352 | Plains Marketing, LP | Cushing, OK 74023 | Oil Operator | Jan 2012 |
| 353 | PNG Operating Company | Oklahoma City, OK 73172 | Oil & Gas Operator | Dec 2025 |
| 354 | Portfolio Oil Corporation | Oklahoma City, OK 73119 | Oil & Gas Operator | May 2013 |
| 355 | Presidio Exploration, Inc. | Englewood, CO 80155 | Oil & Gas Operator | May 1999 |
| 356 | Presidio Petroleum LLC | Canadian, TX 79014 | Oil & Gas Operator | Dec 2025 |
| 357 | Pride Energy Company | Tulsa, OK 74170 | Oil & Gas Operator | Dec 2025 |
| 358 | Princess Three Corporation | Henderson, TX 75653 | Oil & Gas Operator | Apr 2020 |
| 359 | Princess Three Operating, LLC | Henderson, TX 75653 | Oil & Gas Operator | Dec 2025 |
| 360 | Proline Energy Resources Inc | Sugar Land, TX 77479 | Oil & Gas Operator | Dec 2025 |
| 361 | Protege Energy LLC | Tulsa, OK 74135 | Oil & Gas Operator | Jan 2018 |
| 362 | Qep Energy Company | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 363 | Quanah Panhandle, LLC | Traverse City, MI 49684 | Oil & Gas Operator | Dec 2025 |
| 364 | Quantum Resources Management LLC | Houston, TX 77010 | Oil & Gas Operator | Oct 2025 |
| 365 | Questa Energy Corporation | Amarillo, TX 79159 | Oil & Gas Operator | Dec 2025 |
| 366 | Questar Expl. And Prod. Co. | Salt Lake Cty, UT 84145 | Oil & Gas Operator | Jul 2011 |
| 367 | R & A Moore, Inc. | Cleburne, TX 76033 | Oil & Gas Operator | Dec 2025 |
| 368 | R.E.D. Resources, Inc. | Perryton, TX 79070 | Oil & Gas Operator | Apr 2004 |
| 369 | Ram Operating Inc. | Browns, IL 62818 | Oil & Gas Operator | Aug 2008 |
| 370 | Range Production Company | Fort Worth, TX 76102 | Oil & Gas Operator | Sep 2021 |
| 371 | Range Production Company, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Oct 2025 |
| 372 | Raydon Exploration, Inc. | Oklahoma City, OK 73118 | Oil & Gas Operator | Dec 2025 |
| 373 | Raymond Oil Co., Inc. | Wichita, KS 67201 | Oil & Gas Operator | Jun 2025 |
| 374 | Red Willow Mid-Continent, LLC | Ignacio, CO 81137 | Oil & Gas Operator | Oct 2009 |
| 375 | Redstone Oil & Gas Company | Dallas, TX 75225 | Oil & Gas Operator | Jan 2020 |
| 376 | Redstone Operating, Inc. | Austin, TX 78734 | Oil & Gas Operator | Jan 2015 |
| 377 | Remnant Energy, Inc. | Perryton, TX 79070 | Oil & Gas Operator | Dec 2025 |
| 378 | Remora Operating LLC | Houston, TX 77056 | Oil & Gas Operator | Dec 2025 |
| 379 | Resource Oil And Gas, LLC | Oklahoma City, OK 73114 | Oil & Gas Operator | Dec 2025 |
| 380 | Revolution Operating Company,LLC | Oklahoma City, OK 73134 | Oil & Gas Operator | Jul 2024 |
| 381 | Ricks Exploration, Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Mar 2008 |
| 382 | Rio Petroleum, Inc. | Amarillo, TX 79102 | Oil & Gas Operator | Dec 2025 |
| 383 | RKK Production Company | Mustang, OK 73064 | Oil & Gas Operator | Oct 2025 |
| 384 | RTC Resources, LLP | Weatherford, OK 73096 | Oil & Gas Operator | Dec 2025 |
| 385 | Sabine Oil & Gas LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2017 |
| 386 | Samedan Oil Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2019 |
| 387 | Samson Hydrocarbons Company | Tulsa, OK 74103 | Oil & Gas Operator | Nov 2016 |
| 388 | Samson Lone Star LP | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2007 |
| 389 | Samson Lone Star, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2025 |
| 390 | Samson Resources Company | Tulsa, OK 74103 | Oil & Gas Operator | Oct 2025 |
| 391 | Sand Springs Oil & Gas Co. | Tulsa, OK 74136 | Oil & Gas Operator | Dec 2025 |
| 392 | Sandia Operating Corp. | San Antonio, TX 78270 | Oil & Gas Operator | May 2010 |
| 393 | Sandlot Oil & Gas LLC | Gruver, TX 79040 | Oil & Gas Operator | Dec 2025 |
| 394 | Sandridge Exploration And Production LLC | Oklahoma City, OK 73104 | Oil & Gas Operator | Dec 2025 |
| 395 | Santa Fe Snyder Corporation | Houston, TX 77024 | Oil & Gas Operator | Oct 2000 |
| 396 | SCS Newton Oil LLC | Perryton, TX 79070 | Oil & Gas Operator | Dec 2025 |
| 397 | Seagull Energy E & P Inc | Houston, TX 77002 | Oil & Gas Operator | Jan 2015 |
| 398 | SGP Operating LLC | Dallas, TX 75205 | Oil & Gas Operator | Dec 2025 |
| 399 | Sheridan Energy,Inc. | Houston, TX 77002 | Oil & Gas Operator | Feb 2000 |
| 400 | Shidler, Mark L., Inc. | Houston, TX 77055 | Oil & Gas Operator | Dec 2025 |