| 1 | Gas Producing Enterprises Inc. | | Oil & Gas Operator | Oct 1985 |
| 2 | Genesis Petroleum Corp. | Fort Worth, TX 76116-7151 | Oil & Gas Operator | Mar 2011 |
| 3 | Getty Oil Company | Hays, KS 67601 | Oil & Gas Operator | Mar 2015 |
| 4 | Goodrich Oil Company | Shreveport, LA 71101 | Oil & Gas Operator | Nov 2001 |
| 5 | Goodrich Petroleum Company | Houston, TX 77002 | Oil & Gas Operator | Feb 2022 |
| 6 | Graham Expl LTD-DRLG PRNRSHP | | Oil & Gas Operator | Aug 1984 |
| 7 | Graham Oil And Gas, LTD. | Covington, LA 70434-3134 | Oil & Gas Operator | Aug 2013 |
| 8 | Graham Royalty LTD | Covington, LA 70434 | Oil & Gas Operator | Jul 2007 |
| 9 | Graham-McCormick Oper. PRTSHP. | | Oil & Gas Operator | Aug 1989 |
| 10 | Grand Operating, Inc. | Addison, TX 75001 | Oil & Gas Operator | Dec 2020 |
| 11 | Greka Am Inc | Santa Maria, CA 93454 | Oil & Gas Operator | May 2013 |
| 12 | Grigsby Petroleum Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Mar 2025 |
| 13 | Gruy Petroleum Management Co. | Irving, TX 75014 | Oil & Gas Operator | Nov 2014 |
| 14 | GT Energy | | Oil & Gas Operator | Mar 1993 |
| 15 | Gulf Coast Crude O&G Co., Inc. | | Oil & Gas Operator | May 1982 |
| 16 | Gulf Oil Corp. | Denver, CO 80201-0599 | Oil & Gas Operator | Dec 2012 |
| 17 | Gulf South Operators, Inc. | New Orleans, LA 70130 | Oil & Gas Operator | Oct 2015 |
| 18 | Gulf South Pipeline Company, LLC | | Oil & Gas Operator | Jan 2025 |
| 19 | Gulf South Pipeline Company, LP | Houston, TX 77046 | Oil & Gas Operator | Dec 2020 |