| 5001 | Woodlawn Energy Dev., L.L.C. | | Oil & Gas Operator | Aug 2006 |
| 5002 | Woodpecker Corp. | | Oil & Gas Operator | Jun 2024 |
| 5003 | Woods & Deas | | Oil & Gas Operator | Jan 1984 |
| 5004 | Woods & Deas-Dobie | | Oil & Gas Operator | Aug 1983 |
| 5005 | Woods Operating Co., Inc. | Shreveport, LA 71136 | Oil & Gas Operator | Dec 2020 |
| 5006 | Woods Petroleum Corporation | Oklahoma City, OK 73112 | Oil & Gas Operator | Mar 2015 |
| 5007 | Woods, Et Al | | Gas Operator | Sep 1990 |
| 5008 | Wooldridge Land & Cattle, LLC | | Oil Operator | Jul 2024 |
| 5009 | Wooldridge Production Co.,LTD. | | Oil & Gas Operator | Apr 2008 |
| 5010 | Wooldridge Production, L.L.C. | | Oil Operator | Mar 2005 |
| 5011 | Woolf & Magee, Inc. | | Oil & Gas Operator | Oct 1991 |
| 5012 | Workover One, Inc. | | Oil & Gas Operator | Jul 1989 |
| 5013 | World Producers, Inc. | Dallas, TX 75201 | Oil & Gas Operator | Nov 1994 |
| 5014 | Worldwide Energy Corp. | Freer, TX 78357 | Oil & Gas Operator | Jan 1997 |
| 5015 | Wright Production Company | | Oil Operator | Jun 1990 |
| 5016 | WRT Energy Corporation | Oklahoma City, OK 73118 | Oil & Gas Operator | May 1998 |
| 5017 | WSF, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Jun 2013 |
| 5018 | Wylee Petroleum Corporation | | Oil & Gas Operator | Dec 1984 |
| 5019 | Wynn-Crosby Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | May 2005 |
| 5020 | Wynn-Crosby Operating, LTD. | Dallas, TX 75201 | Oil & Gas Operator | Nov 2024 |
| 5021 | Wytex Production Corporation | Fort Smith, AR 72903 | Oil & Gas Operator | Jan 2020 |
| 5022 | XCL-Louisiana, Inc. | | Oil & Gas Operator | Aug 1993 |
| 5023 | Xeric Oil & Gas Corporation | Midland, TX 79702 | Oil & Gas Operator | Apr 2014 |
| 5024 | Xplor Energy Operating Co. | Houston, TX 77079 | Oil & Gas Operator | Jan 2012 |
| 5025 | XTO Energy Inc. | Spring, TX 77389 | Oil & Gas Operator | Nov 2024 |
| 5026 | Xtra Energy Corporation | | Oil & Gas Operator | Jun 1989 |
| 5027 | Yasny Corporation | | Oil Operator | Nov 1991 |
| 5028 | Yates Oil Company | | Oil Operator | Jul 1990 |
| 5029 | Yellow Dog Oil Company | | Oil Operator | Apr 1988 |
| 5030 | Yellow Rock, LLC | | Oil & Gas Operator | Jun 2024 |
| 5031 | Yentzen Investments, Inc. | Sugar Land, TX 77478 | Oil Operator | May 1993 |
| 5032 | Yentzen Production, Inc. | | Oil Operator | Mar 1987 |
| 5033 | Youngblood Enterprises | | Gas Operator | Dec 1983 |
| 5034 | Youngblood Enterprises, Inc. | | Oil & Gas Operator | Jan 1992 |
| 5035 | Yuma E & P Company, Inc. | Houston, TX 77027 | Oil & Gas Operator | Nov 2024 |
| 5036 | Yuma Petroleum Company | Houston, TX 77027 | Oil & Gas Operator | Aug 2002 |
| 5037 | Z C Ambrose-G L Blaxton, Jr. | | Oil & Gas Operator | Mar 1980 |
| 5038 | Zachry Exploration, Inc. | San Antonio, TX 78205 | Oil & Gas Operator | Nov 2024 |
| 5039 | Zachry Exploration, LLC | San Antonio, TX 78224 | Oil & Gas Operator | Nov 2024 |
| 5040 | Zachry Exploration, LTD. | San Antonio, TX 78205 | Oil & Gas Operator | Jan 2009 |
| 5041 | Zad, Inc. | | Oil Operator | Jun 2001 |
| 5042 | Zadeck Energy Group Inc | | Oil & Gas Operator | Jun 2013 |
| 5043 | Zam'S Production Company | | Oil Operator | Sep 2004 |
| 5044 | Zarvona Energy LLC | Houston, TX 77002 | Oil & Gas Operator | Nov 2024 |
| 5045 | Zeagler Enterprises, Inc. | Shreveport, LA 71115 | Oil & Gas Operator | Mar 2009 |
| 5046 | Zeit Exploration Co., Inc. | | Oil & Gas Operator | May 1994 |
| 5047 | Zenergy Inc | Tulsa, OK 74136 | Oil & Gas Operator | Sep 2024 |
| 5048 | Zenergy Operating Company, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Dec 2016 |
| 5049 | Zercon Oil & Gas, Inc. | | Oil Operator | Oct 2003 |
| 5050 | Zgen, Inc. | | Oil & Gas Operator | Jul 1990 |
| 5051 | Zilkha Energy Company | Houston, TX 77046 | Oil & Gas Operator | Oct 2002 |
| 5052 | Zinke & Trumbo, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Mar 2007 |
| 5053 | Zinn Petroleum Co. | Houston, TX 77024 | Oil & Gas Operator | Nov 2021 |
| 5054 | Zone Energy, LLC | Houston, TX 77251 | Oil & Gas Operator | Jul 2024 |