| 1 | C & J Exploration LLC | Colorado Springs, CO 80920-3946 | Oil & Gas Operator | Oct 2022 |
| 2 | C & L Enterprise Of Wagoner | Coweta, OK 74429-9657 | Oil Operator | Mar 2001 |
| 3 | Campbell Production Company | Tulsa, OK 74137-4145 | Oil & Gas Operator | Mar 2015 |
| 4 | Cannuck Resources Inc | Nowata, OK 74048 | Oil & Gas Operator | Aug 2000 |
| 5 | Canok International Inc | Okmulgee, OK 74447 | Oil & Gas Operator | Oct 2024 |
| 6 | Chevron USA Inc | Midland, TX 79706 | Oil & Gas Operator | Dec 2024 |
| 7 | Cimarron Valley Energy Inc | Stillwater, OK 74076 | Oil Operator | Apr 2015 |
| 8 | Clemishire Bryan | Hominy, OK 74035 | Oil & Gas Operator | Nov 2014 |
| 9 | Consolidated Exploration Company | Nichols Hill, OK 73116 | Oil & Gas Operator | Apr 2015 |
| 10 | Cornelius Oil Company | Kellyville, OK 74039-0459 | Oil & Gas Operator | Jul 2015 |
| 11 | Cornelius Tony | Sapulpa, OK 74066-5845 | Oil & Gas Operator | Jul 2024 |
| 12 | Coronado Great Plains LLC | Tulsa, OK 74137-2832 | Gas Operator | Apr 2013 |
| 13 | Covenant Oil Corp | Broken Arrow, OK 74014 | Oil & Gas Operator | May 2013 |
| 14 | Creek Ellis | Haskell, OK 74436 | Oil & Gas Operator | Mar 2012 |
| 15 | Crude Marketing & Trans Inc | Tulsa, OK 74159 | Oil & Gas Operator | Sep 2017 |
| 16 | CW Investments | Okmulgee, OK 74447-4026 | Oil & Gas Operator | Oct 2024 |