| 401 | Rue Johnny B | Duncan, OK 73533-2019 | Oil & Gas Operator | Jan 2025 |
| 402 | Ruh Oil Company | Collinsville, OK 74021 | Oil & Gas Operator | Oct 2025 |
| 403 | Rumble Energy LLC | Skiatook, OK 74070 | Oil & Gas Operator | Feb 2026 |
| 404 | Rumley Robert A & Associates | Tulsa, OK 74135-1907 | Oil Operator | Sep 2025 |
| 405 | Rupe Oil Company Inc | Wichita, KS 67278 | Oil & Gas Operator | Sep 2025 |
| 406 | Rush Creek Operating LLC | McKinney, TX 75070 | Oil & Gas Operator | Feb 2026 |
| 407 | Rush-Andrus Engineering | Royse City, TX 75189-1210 | Oil & Gas Operator | Feb 2022 |
| 408 | Russell Carl G | Coweta, OK 74429 | Oil & Gas Operator | Mar 2015 |
| 409 | Russell D Meloy Oil & Gas Co | Enid, OK 73703-1623 | Oil & Gas Operator | Nov 2025 |
| 410 | Russell Oil Company | Haskell, OK 74436 | Oil & Gas Operator | Apr 2014 |
| 411 | Russell, John R | | Oil Operator | Mar 2025 |
| 412 | Rust Oil Corp. | Fort Worth, TX 76121 | Oil & Gas Operator | Feb 2026 |
| 413 | Rustler Energy LLC | Lindsay, OK 73052 | Oil & Gas Operator | Oct 2025 |
| 414 | RW Oil & Gas LLC | Lamont, OK 74643 | Oil & Gas Operator | Nov 2025 |
| 415 | Rwit Company Inc | Tulsa, OK 74131-4255 | Oil & Gas Operator | Jul 2018 |
| 416 | Ry-Co Petroleum | Wann, OK 74083 | Oil & Gas Operator | Feb 2017 |
| 417 | Ryan Petroleum Corp | Oklahoma City, OK 73102-9024 | Oil & Gas Operator | Aug 1994 |
| 418 | Ryan Petroleum Operating Inc | Oklahoma City, OK 73102-9024 | Oil & Gas Operator | May 1999 |
| 419 | Ryder Scott Oil Company | Wichita Falls, TX 76307 | Oil & Gas Operator | Dec 2005 |