| 1901 | Southridge Operating Company | San Marcos, TX 78667 | Oil & Gas Operator | Feb 2026 |
| 1902 | Southstar Energy Corporation | Ardmore, OK 73401 | Gas Operator | Aug 1990 |
| 1903 | Southstar Oil And Gas Inc | Andover, KS 67002-0123 | Oil & Gas Operator | Jul 2020 |
| 1904 | Southstone Energy, LLC | Austin, TX 78735 | Oil Operator | Feb 2026 |
| 1905 | Southwell Russell C | Warren, PA 16365-3686 | Oil & Gas Operator | Dec 2022 |
| 1906 | Southwell William R | Warren, PA 16365-1259 | Oil & Gas Operator | Dec 2017 |
| 1907 | Southwest Energy Devel.,Inc. | Sugar Land, TX 77478 | Oil & Gas Operator | Jul 2007 |
| 1908 | Southwest Energy Development Inc | Bison, OK 73720 | Oil & Gas Operator | Nov 2025 |
| 1909 | Southwest Exploration Company | Oklahoma City, OK 73132-2230 | Oil & Gas Operator | Jun 2017 |
| 1910 | Southwest Gas Producing Co Inc | | Oil & Gas Operator | Nov 1994 |
| 1911 | Southwest Gas St | | Oil & Gas Operator | Dec 1981 |
| 1912 | Southwest Gas Storage Company | | Gas Operator | Sep 2025 |
| 1913 | Southwest Gas Systems, Inc. | Spring, TX 77379 | Oil & Gas Operator | Feb 2026 |
| 1914 | Southwest Gathering Company | Alice, TX 78332 | Oil & Gas Operator | Feb 2026 |
| 1915 | Southwest General Dev., Inc. | | Oil & Gas Operator | Dec 2003 |
| 1916 | Southwest Ind Investment Co | | Gas Operator | Oct 1983 |
| 1917 | Southwest Investment Fund, Inc. | Dallas, TX 75229 | Oil & Gas Operator | Aug 2003 |
| 1918 | Southwest Land & Minerals, Inc. | Corpus Chrsti, TX 78471 | Oil & Gas Operator | Aug 2003 |
| 1919 | Southwest Loop 1604, LTD. | San Antonio, TX 78209 | Oil Operator | Sep 2022 |
| 1920 | Southwest Mississippi Oil & Gas, LLC. | | Oil Operator | Dec 2025 |
| 1921 | Southwest Oil & Land, Inc. | Corpus Chrsti, TX 78460 | Oil & Gas Operator | Dec 1999 |
| 1922 | Southwest Oil Properties, Inc. | | Oil & Gas Operator | Feb 1996 |
| 1923 | Southwest Operating Company | Overland Park, KS 66212 | Oil & Gas Operator | Mar 2012 |
| 1924 | Southwest Operating Inc. | | Oil & Gas Operator | Dec 2024 |
| 1925 | Southwest Operating, Inc.-Tyler | Tyler, TX 75701 | Oil & Gas Operator | Feb 2026 |
| 1926 | Southwest Petroleum | San Antonio, TX 78253 | Oil & Gas Operator | Feb 2026 |
| 1927 | Southwest Petroleum Corp | Drumright, OK 74030 | Oil & Gas Operator | Mar 2018 |
| 1928 | Southwest Petroleum Oil & Gas Explor LLC | San Bernardino, CA 92404-1010 | Oil & Gas Operator | Jun 2022 |
| 1929 | Southwest Production Co | Richardson, TX BADADDR | Oil & Gas Operator | Apr 1997 |
| 1930 | Southwest Resources, Inc. | Brenham, TX 77834 | Oil & Gas Operator | Feb 2026 |
| 1931 | Southwest Rig Service | | Oil & Gas Operator | Nov 1998 |
| 1932 | Southwest Royalties, Inc. | Midland, TX 79710 | Oil & Gas Operator | Feb 2026 |
| 1933 | Southwest-Operating | Penwell, TX 79776 | Oil & Gas Operator | Feb 2026 |
| 1934 | Southwestern Electric Power Co | Dallas, TX 75266 | Oil & Gas Operator | Dec 1989 |
| 1935 | Southwestern Energy Prod Co | Houston, TX 77032 | Oil & Gas Operator | Jun 2015 |
| 1936 | Southwestern Exploration Consultants Inc | Oklahoma City, OK 73118-1116 | Oil & Gas Operator | Nov 2025 |
| 1937 | Southwestern Inc | Hobbs, NM 88240 | Oil Operator | Oct 2009 |
| 1938 | Southwestern Oil Corporation | Oklahoma City, OK 73106 | Oil & Gas Operator | Dec 2025 |
| 1939 | Southwestern Production Corporation | Lakewood, CO 80228 | Oil & Gas Operator | Dec 2025 |
| 1940 | Southwind Consulting | Pratt, KS 67124 | Oil Operator | Oct 1997 |
| 1941 | Southwind Exploration, LLC | Venice, FL 34293 | Oil & Gas Operator | Sep 2003 |
| 1942 | Southwind Oil & Gas LLC | | Oil & Gas Operator | Dec 2023 |
| 1943 | Southwind Petroleum Corp. | Wichita, KS 67203 | Oil & Gas Operator | Jun 2022 |
| 1944 | Sovereign Eagle, LLC | Roswell, NM 88202 | Oil & Gas Operator | Jul 2018 |
| 1945 | Sovereign Energy Corp. | | Oil Operator | Dec 2001 |
| 1946 | Sovereign Operating Company, LLC | Denver, CO 80202 | Oil & Gas Operator | Apr 2016 |
| 1947 | Sovereign Petroleum Company, LLC | Oklahoma City, OK 73120 | Oil & Gas Operator | Jul 2013 |
| 1948 | Sowers William & Sara | Blue Rock, OH 43720 | Oil Operator | Dec 2022 |
| 1949 | Sowle Exploratio | | Oil Operator | Aug 1986 |
| 1950 | Sowle Explorations | | Oil Operator | Dec 2002 |
| 1951 | Soxgi LLC | Andrews, TX 79714 | Gas Operator | Dec 2025 |
| 1952 | Sozo Natural Resources LLC | Houston, TX 77056 | Oil & Gas Operator | Feb 2026 |
| 1953 | SP Energy Development Company | Seattle, WA 98101-3277 | Oil & Gas Operator | Mar 2015 |
| 1954 | Space Production Inc. | Monahans, TX 79756 | Oil & Gas Operator | Feb 2026 |
| 1955 | Spacht, James W. & Shelly F | Ripley, NY 14775 | Gas Operator | Dec 2024 |
| 1956 | Spade Energy L.L.C. | Wichita Falls, TX 76308 | Oil & Gas Operator | Feb 2026 |
| 1957 | Spahn Keith H | Butler, PA 16002-9176 | Oil & Gas Operator | Dec 2018 |
| 1958 | Spain Oil Company | Somerset, TX 78069 | Oil & Gas Operator | Feb 2026 |
| 1959 | Spain, Mack | Breckenridge, TX 76424 | Oil & Gas Operator | Mar 1996 |
| 1960 | Spalding Energy, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Feb 2026 |
| 1961 | Spalsbury, Arthur L | Hays, KS 67601 | Oil Operator | Aug 2001 |
| 1962 | Spark'S Energy Inc | Perry, OK 73077 | Oil & Gas Operator | Nov 2014 |
| 1963 | Sparkman Rodger E | Jenks, OK 74037-0267 | Oil Operator | Sep 2018 |
| 1964 | Sparks Daniel M | Chickasha, OK 73023-1435 | Oil & Gas Operator | Apr 2014 |
| 1965 | Sparks Greg | Afton, OK 74331 | Oil & Gas Operator | Nov 2025 |
| 1966 | Sparks Harold | Radnor, OH 43066 | Oil & Gas Operator | Dec 1987 |
| 1967 | Sparks Mick Oil Company Inc | Jennings, OK 74038-0250 | Oil & Gas Operator | Dec 2025 |
| 1968 | Sparks Petroleum Company | Oklahoma City, OK 73128 | Oil & Gas Operator | Mar 1998 |
| 1969 | Sparks Resources Inc | Bristow, OK 74010 | Oil & Gas Operator | Dec 2025 |
| 1970 | Sparks, Pearlman E | Mazie, KY 41160 | Oil Operator | Dec 2015 |
| 1971 | Sparks, Sidney A., Trustee | Alice, TX 78332 | Oil & Gas Operator | Jun 1996 |
| 1972 | Sparlin J L | Oklahoma City, OK 73156-1446 | Oil Operator | Oct 2025 |
| 1973 | Sparrow Oil & Gas LLC | | Oil & Gas Operator | Jan 2026 |
| 1974 | Sparrow Operating LLC | Comanche, OK 73529-9747 | Oil Operator | Nov 2025 |
| 1975 | Sparta Energy Corp | Oak Brook, IL 60521 | Oil & Gas Operator | Dec 1985 |
| 1976 | Sparta Exploration LLC | Houston, TX 77279 | Oil & Gas Operator | Feb 2026 |
| 1977 | Spartagus Corporation | Grand Saline, TX 75140 | Oil & Gas Operator | Sep 2004 |
| 1978 | Spartan Oil Corporation | Abilene, TX 79601 | Oil & Gas Operator | Aug 2003 |
| 1979 | Spartan Operating Company, Inc. | Tyler, TX 75702 | Oil & Gas Operator | Feb 2013 |
| 1980 | Spartan Petroleum Corporation | Houston, TX 77079 | Oil & Gas Operator | Oct 1987 |
| 1981 | Spartan Resource MGMT Corp | Rural Valley, PA 16249-0326 | Gas Operator | Dec 2024 |
| 1982 | Spartan Resources LLC | Oklahoma City, OK 73116 | Oil & Gas Operator | Dec 2025 |
| 1983 | Spartan Royalties, LLC | | Oil Operator | Dec 2024 |
| 1984 | Spartywood Prod Inc | Spartansburg, PA 16434-1627 | Gas Operator | Dec 2015 |
| 1985 | SPC Resources, LLC | Midland, TX 79701 | Oil & Gas Operator | Feb 2024 |
| 1986 | Spear Production Company, Inc. | Shreveport, LA 71161 | Oil Operator | Feb 2026 |
| 1987 | Spearco Oil | Electra, TX 76360 | Oil & Gas Operator | Aug 2003 |
| 1988 | Spearpoint Energy LLC | Seminole, OK 74818-1247 | Oil Operator | Jun 2015 |
| 1989 | Spears Terry | Osage, OK 74054 | Oil Operator | Oct 2025 |
| 1990 | Speartex Grain Company | Gruver, TX 79040 | Oil & Gas Operator | Feb 2026 |
| 1991 | Speartip Energy, LLC | Katy, TX 77450 | Oil Operator | Feb 2026 |
| 1992 | Specht Farms | Piqua, KS 66761 | Oil Operator | Nov 2009 |
| 1993 | Specht Oil | Iola, KS 66749 | Oil Operator | Mar 1998 |
| 1994 | Special Energy Corp. | Stillwater, OK 74076 | Oil & Gas Operator | Feb 2026 |
| 1995 | Special JHR Corp | Bridgeville, PA 15017 | Oil & Gas Operator | Feb 2026 |
| 1996 | Specialized Technological Threading, Inc., | | Oil & Gas Operator | Oct 2019 |
| 1997 | Speckle Trout Operating LLC | Houston, TX 77092 | Oil Operator | Feb 2026 |
| 1998 | Speco Oil Company | | Oil & Gas Operator | Feb 1980 |
| 1999 | Spectral Oil & Gas Corporation | Humble, TX 77338 | Oil Operator | Feb 2026 |
| 2000 | Spectrum Energy Inc | Scottsdale, AZ 85257 | Oil & Gas Operator | Oct 2003 |