| 301 | McCarter, W. B. Jr. | Houston, TX 77063 | Oil & Gas Operator | Feb 2002 |
| 302 | McCauley Production | Graham, TX 76450 | Oil Operator | Apr 2024 |
| 303 | McCauley, F. R. | Houston, TX 77002 | Oil & Gas Operator | Apr 2000 |
| 304 | McClelland Creek Properties,Inc. | Pampa, TX 79066 | Oil & Gas Operator | Apr 2024 |
| 305 | McClure Brothers | Denton, TX 76210 | Oil & Gas Operator | Apr 2024 |
| 306 | McClure Oil Company, Inc. | Midland, TX 79701 | Oil & Gas Operator | Apr 2024 |
| 307 | McClure, J.D. Trust | Denton, TX 76209 | Oil & Gas Operator | Apr 2024 |
| 308 | McClymond, B. W. | Breckenridge, TX 76424 | Oil & Gas Operator | Jul 2020 |
| 309 | McClymond, Inc. | Breckenridge, TX 76424 | Oil & Gas Operator | Jul 2001 |
| 310 | McClymond, LTD. | Breckenridge, TX 76424 | Oil & Gas Operator | Dec 2009 |
| 311 | McCombs Energy LLC | Houston, TX 77056 | Oil & Gas Operator | Jan 2006 |
| 312 | McCombs Energy, LTD. | Houston, TX 77056 | Oil & Gas Operator | Aug 2017 |
| 313 | McCommons Oil Company | Dallas, TX 75201 | Oil & Gas Operator | Apr 2024 |
| 314 | McCool John E | Youngsville, PA 16371 | Oil & Gas Operator | Feb 2024 |
| 315 | McCord Production, LTD. | Houston, TX 77002 | Gas Operator | Feb 1997 |
| 316 | McCormack, Lowell Ray | Gainesville, TX 76240 | Oil & Gas Operator | Dec 1993 |
| 317 | McCormack, Paul H. | Gainesville, TX 76241 | Oil & Gas Operator | Sep 2003 |
| 318 | McCormick Operating, L.L.C. | Olney, TX 76374 | Oil Operator | Sep 2015 |
| 319 | McCormick Production Co, Inc. | Oil City, LA 71061 | Oil & Gas Operator | Apr 2024 |
| 320 | McCown Engineering | Wichita Falls, TX 76310 | Oil & Gas Operator | Apr 2024 |
| 321 | McCoy Petroleum Corporation | Wichita, KS 67207 | Oil & Gas Operator | Mar 2024 |
| 322 | McCracken, H. L. Company | Wichita Falls, TX 76302 | Oil & Gas Operator | Apr 2024 |
| 323 | McCrary & Franklin, Inc. | Post, TX 79356 | Oil & Gas Operator | May 2012 |
| 324 | McCrary Oil Company, Inc. | College Sta, TX 77840 | Oil & Gas Operator | Sep 2019 |
| 325 | McCrea Exploration Company, Inc. | Carrollton, TX 75007 | Oil & Gas Operator | Nov 1995 |
| 326 | McCullis Resources Co., Inc. | Littleton, CO 80161 | Oil & Gas Operator | Jan 2024 |
| 327 | McCulliss Resources Co Inc | Littleton, CO 80161-3248 | Oil & Gas Operator | Jun 2009 |
| 328 | McCurdy Energy LLC | Midland, TX 79705 | Oil Operator | Apr 2024 |
| 329 | McCurdy Oil Co. | Fort Worth, TX 76116 | Oil & Gas Operator | Jan 2024 |
| 330 | McCutchin Petroleum Corporation | Dallas, TX 75225 | Oil & Gas Operator | Apr 2024 |
| 331 | McCutchin, Gene | Dallas, TX 75380 | Oil & Gas Operator | Aug 2003 |
| 332 | McCutchin, Jerry | Dallas, TX 75380 | Oil & Gas Operator | Mar 2008 |
| 333 | McDaniel Company, Inc., The | Dallas, TX 75230 | Oil & Gas Operator | Apr 2024 |
| 334 | McDaniel Oil Co. | Marble Falls, TX 78654 | Oil & Gas Operator | Apr 2024 |
| 335 | McDaniel, Willard | Iraan, TX 79744 | Oil & Gas Operator | Nov 2004 |
| 336 | McDaniel, Willard Jr. Oil Co. | Marble Falls, TX 78654 | Oil & Gas Operator | Mar 2005 |
| 337 | McDay Energy Corp. | Dallas, TX 75206 | Oil & Gas Operator | Apr 2024 |
| 338 | McDonald & Johnson Resources,LLC | Cypress, TX 77429 | Oil & Gas Operator | Dec 2010 |
| 339 | McDonald & Pomeroy Operating Co. | Pasadena, TX 77506 | Oil & Gas Operator | Aug 2003 |
| 340 | McDonald Energy, Inc. | Granbury, TX 76049 | Oil & Gas Operator | Apr 2024 |
| 341 | McDonald Production | Lubbock, TX 79408 | Oil & Gas Operator | Mar 2003 |
| 342 | McDonald Production, LLC | Lubbock, TX 79408 | Oil Operator | Apr 2024 |
| 343 | McDonald Resources, LLC | Jefferson, TX 75657 | Oil & Gas Operator | Apr 2024 |
| 344 | McDonald, Joe | Burkburnett, TX 76354 | Oil & Gas Operator | Aug 1995 |
| 345 | McDonald, R. A. Oil Co. | Borger, TX 79008 | Oil & Gas Operator | Oct 2002 |
| 346 | McDonald, Richard A. | Fredericksbrg, TX 78624 | Oil & Gas Operator | Apr 2024 |
| 347 | McDonnold Operating, Inc. | Midland, TX 79701 | Oil & Gas Operator | Apr 2024 |
| 348 | McEna Inc | Tulsa, OK 74135 | Oil & Gas Operator | Jul 2005 |
| 349 | McEuen, Billy Oil Co. | Bowie, TX 76230 | Oil & Gas Operator | Dec 2016 |
| 350 | McEver Oil Company Inc. | Austin, TX 78789 | Oil & Gas Operator | Mar 2008 |
| 351 | McFadden Energy TX, LLC | Lakewood, NY 14750 | Oil Operator | Apr 2024 |
| 352 | McFarland & Scobey, Inc. | El Paso, TX 79947 | Oil & Gas Operator | Apr 2024 |
| 353 | McFarland Energy, Inc. | New Orleans, LA 70160 | Oil & Gas Operator | Dec 2009 |
| 354 | MCG Oil & Gas Operating, LLC | Archer City, TX 76351 | Oil & Gas Operator | Sep 2023 |
| 355 | McGee Drilling Corporation | Midland, TX 79702 | Oil & Gas Operator | Apr 2024 |
| 356 | McGee, Tom Corporation | Booker, TX 79005 | Oil & Gas Operator | Dec 2023 |
| 357 | McGehee, George T. Operating Co. | Houston, TX 77024 | Oil & Gas Operator | Oct 1997 |
| 358 | McGhee Exploration And Prod. Co. | Houston, TX 77019 | Oil & Gas Operator | Feb 2003 |
| 359 | McGoldrick Oil Company | Shreveport, LA 71129 | Oil & Gas Operator | Jul 2020 |
| 360 | McGowan Working Partners | Jackson, MS 39296 | Oil & Gas Operator | Dec 2000 |
| 361 | McGowan Working Partners, Inc. | Jackson, MS 39296 | Oil & Gas Operator | Apr 2024 |
| 362 | McGowen Resources Co., Inc. | Dallas, TX 75206 | Oil & Gas Operator | Aug 2003 |
| 363 | McGuffin, Joe Jr. | Christoval, TX 76935 | Oil & Gas Operator | Apr 2024 |
| 364 | McGuire Brothers | Phoenix, AZ 85045 | Oil & Gas Operator | Apr 2024 |
| 365 | McIver, Inc | San Angelo, TX 76903 | Oil & Gas Operator | Apr 2024 |
| 366 | McKay Oil | Portales, NM 88130 | Oil & Gas Operator | Apr 1996 |
| 367 | McKay Operating LLC | Groom, TX 79039 | Oil & Gas Operator | Oct 2023 |
| 368 | McKee, Kenneth W. Oil Co. | Graham, TX 76450 | Oil & Gas Operator | Aug 2011 |
| 369 | McKeever, Tyra, Swenson Venture | Stamford, TX 79553 | Oil & Gas Operator | Apr 1996 |
| 370 | McKenney & Chambers Oil Company | Westbrook, TX 79565 | Oil & Gas Operator | Oct 2003 |
| 371 | McKenzie Operating Company, Inc. | Graham, TX 76450 | Oil & Gas Operator | Aug 2011 |
| 372 | McKenzie Production Company | Houston, TX 77063 | Oil & Gas Operator | May 1995 |
| 373 | McKinney Operating Company | Canadian, TX 79014 | Gas Operator | May 2002 |
| 374 | McKinney, M. H. | Midland, TX 79701 | Oil & Gas Operator | Apr 1995 |
| 375 | McKnight, C. L. | McLeod, TX 75565 | Oil & Gas Operator | Apr 2024 |
| 376 | McKnight, C. L. Oil Co. LLP | McLeod, TX 75565 | Oil & Gas Operator | Apr 2024 |
| 377 | McKnight, J. C. | Jefferson, TX 75657 | Oil & Gas Operator | Nov 2019 |
| 378 | McLain Exploration, Inc. | Boerne, TX 78006 | Oil & Gas Operator | Mar 2008 |
| 379 | McLelland Engineering & MGMT. | Houston, TX 77042 | Oil & Gas Operator | Mar 1999 |
| 380 | McLemore, Laurence | Iowa Park, TX 76367 | Oil & Gas Operator | Apr 2024 |
| 381 | McLeod, George L. Inc. | Houston, TX 77079 | Oil & Gas Operator | Sep 2002 |
| 382 | MCM Operating LLC | Midland, TX 79702 | Oil & Gas Operator | Feb 2024 |
| 383 | McMahon Operating Co., L.C. | Pampa, TX 79066 | Oil & Gas Operator | Dec 2004 |
| 384 | McMahon-Bullington Drilling Co. | Wichita Falls, TX 76307 | Oil & Gas Operator | Mar 1996 |
| 385 | McMahon-Bullington LP | Wichita Falls, TX 76307 | Oil & Gas Operator | Apr 2009 |
| 386 | McMinn Operating Company, Inc. | Hempstead, TX 77445 | Oil & Gas Operator | Apr 2024 |
| 387 | McMoran Oil & Gas LLC | New Orleans, LA 70160 | Oil & Gas Operator | Oct 2021 |
| 388 | McMullan Oil Company | San Antonio, TX 78212 | Oil & Gas Operator | May 2023 |
| 389 | McMurrey, R. J., Production Comp | Tyler, TX 75711 | Oil & Gas Operator | Apr 2024 |
| 390 | McNallen & Griffin | Keller, TX 76244 | Oil & Gas Operator | Apr 2024 |
| 391 | McNallen Oil Co., Inc. | Keller, TX 76244 | Oil & Gas Operator | Apr 2024 |
| 392 | McNic Oil & Gas Midcontinent,Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Jul 1999 |
| 393 | McOsker Bros., Inc. | San Antonio, TX 78264 | Oil & Gas Operator | Aug 2003 |
| 394 | McQueen Ed & Company Inc | Lindsey, OK 73052 | Oil & Gas Operator | Apr 2014 |
| 395 | MCR Operating Group | San Antonio, TX 78209 | Oil & Gas Operator | Apr 2024 |
| 396 | McRae & Henry LTD | Golden, CO 80401 | Oil & Gas Operator | May 2022 |
| 397 | McRae Exploration & Prod., Inc. | Houston, TX 77064 | Oil & Gas Operator | Feb 2017 |
| 398 | McRae, Nathan Rathburn | Hebbronville, TX 78361 | Oil & Gas Operator | Apr 1994 |
| 399 | McShane, J. Inc. | Midland, TX 79702 | Oil & Gas Operator | Apr 2004 |
| 400 | MCZ, Inc. | Houston, TX 77026 | Oil & Gas Operator | Sep 1990 |