| Duval Ranch, Sec. #288 O-4-452 | McGowan Working Partners, Inc. only | Charamousca, South | Duval | 20 | 859K | 170K | by Jan 1993 – Aug 2026 |
| Duval Ranch -59- O-4-1138 | Killam Oil Co., Ltd. only | Govt. Wells, South | Duval | 21 | 799K | 21 | by Jan 1993 – Aug 2026 |
| Duval Ranch Sec. 62 O-4-2874 | Caribbean Energy LLC II only | Seventy-Six, West | Duval | 28 | 509K | 21 | by Jan 1993 – Aug 2026 |
| Duval Ranch, Sec. # 257 a/C 1 O-4-1702 | Killam Oil Co., Ltd. only | Lundell (Pettus) | Duval | 6 | 477K | 19.1K | by Jan 1993 – Jan 2026 |
| Magnolia-Duval Ranch Sec. 208-09 O-4-1083 | Killam Oil Co., Ltd. only | Govt. Wells, N. | Duval | 7 | 136K | 57 | by Jan 1993 – Aug 2026 |
| Duval Ranch Sec. 203 O-4-8921 | Killam Oil Co., Ltd. only | Petrox, N. (Frio 1250) | Duval | 5 | 135K | 57 | by Jan 1993 – Aug 2026 |
| Duval Ranch, Sec. #203 O-4-2114 | Killam Oil Co., Ltd. only | Piedre Lumbre | Duval | 14 | 115K | 69 | by Jan 1993 – Aug 2026 |
| Duval Ranch, Sec. #201, a/C 2 O-4-2113 | Southwest Royalties, Inc. only | Piedre Lumbre | Duval | 2 | 91K | 21 | by Jan 1993 – Apr 2017 |
| Humble-Duval Ranch Sec 204 O-4-11211 | Southwest Royalties, Inc. only | Petrox (Government Wells) | Duval | 4 | 89.2K | 34.3K | by Jan 1993 – Jun 2006 |
| Duval Ranch, Sec. #58 O-4-1696 | Caribbean Energy LLC II only | Lundell | Duval | 9 | 89.2K | 21 | by Jan 1993 – Aug 2026 |
| Duval Ranch -D- O-4-1093 | Hilcorp Energy Company only | Govt. Wells, N. | Duval | 4 | 87.6K | 152 | by Jan 1993 – Aug 2026 |
| Duval Ranch Sec. 106 O-4-7897 | Killam Oil Co., Ltd. only | Hagist Ranch ( Argo) | Duval | 6 | 72.1K | 21 | by Jan 1993 – Mar 2022 |
| Duval Ranch O-4-1089 | Ragars Oil & Gas Co. only | Govt. Wells, N. | Duval | 6 | 64.8K | 115K | by Jan 1993 – Aug 2026 |
| Duval Ranch, Sec. #100, a/C 2 O-4-2112 | Dewbre, Jerry C., Trustee only | Piedre Lumbre | Duval | 6 | 57.2K | 21 | by Jan 1993 – Mar 2015 |
| Duval Ranch 79 Cole -C- Unit O-4-7638 | Killam Oil Co., Ltd. only | D C R-79 | Duval | 13 | 54.1K | 15 | May 1993 – Aug 2026 |
| Duval Ranch Sec. 578 O-4-8767 | Killam Oil Co., Ltd. only | Sarnosa, West | Duval | 3 | 51.4K | 21 | by Jan 1993 – Aug 2026 |
| Duval Ranch Section 281 O-4-8183 | McGowan Working Partners, Inc. only | Charamousca, South | Duval | 1 | 41.9K | 14.7K | by Jan 1993 – Sep 2004 |
| Mag.duval Ranch Sec. 208-209 O-4-9194 | Killam Oil Co., Ltd. only | Govt. Wells, N. (1150) | Duval | 1 | 39.9K | 21 | by Jan 1993 – Aug 2026 |
| Duval Ranch Sec. 106, Acct #3 O-4-4363 | Killam Oil Co., Ltd. only | Hagist Ranch ( Purple Sand) | Duval | 1 | 32.3K | 7 | Mar 1994 – Dec 2002 |
| Humble Duval Ranch Sec. 79 O-4-625 | Killam Oil Co., Ltd. only | D C R-79 | Duval | 6 | 16.4K | 7 | Mar 1994 – Apr 2025 |
| Duval Ranch Sec. 79 O-4-623 | Killam Oil Co., Ltd. only | D C R-79 | Duval | 1 | 15K | 7 | Mar 1994 – Aug 2026 |
| Duval Ranch Sec. 95 O-4-9057 | Killam Oil Co., Ltd. only | Piedre Lumbre (1300) | Duval | 1 | 14.9K | 21 | by Jan 1993 – Mar 2008 |
| Duval Ranch Sec. 201 a/C #5 O-4-1189 | Southwest Royalties, Inc. only | Hagist Ranch ( Queen City Sand) | Duval | 2 | 14.7K | 21 | by Jan 1993 – Feb 1999 |
| Duval Ranch Sec. 101 O-4-8894 | Killam Oil Co., Ltd. only | Brelum (Chernosky) | Duval | 3 | 8.58K | 21 | by Jan 1993 – May 1996 |
| Duval Ranch Sec. 96 O-4-9908 | Southwest Royalties, Inc. only | Petrox (Chernosky, Upper) | Duval | 1 | 7.07K | 19 | by Jan 1993 – Dec 2006 |
| Duval Ranch '79' O-4-14194 | Killam Oil Co., Ltd. only | D C R-79 | Duval | 1 | 3.9K | 0 | Jan 2023 – Aug 2026 |
| Humble-Duval Ranch Sec. 79 a/C 2 O-4-4635 | Killam Oil Co., Ltd. only | Seventy-Six, South | Duval | 1 | 1.39K | 0 | May 1995 – Feb 2001 |
| Duval Ranch, Sec. #100, a/C 1 O-4-2111 | Dewbre, Jerry C., Trustee only | Piedre Lumbre | Duval | 2 | 1.28K | 0 | Jan 2011 – Mar 2015 |
| Duval Ranch Sec. 203 O-4-13939 | Killam Oil Co., Ltd. only | Petrox (Chernosky, Upper) | Duval | 1 | 0 | 0 | — |
| Duval Ranch Sec. 196 O-4-1656 | Killam Oil Co., Ltd. only | Lopez, North (Lopez) | Duval | 4 | 0 | 0 | — |
| Duval Ranch Sec. 57 O-4-9384 | Killam Oil Co., Ltd. only | Govt. Wells, South | Duval | 2 | 0 | 0 | — |
| Duval Ranch Sec. 202 O-4-9714 | Killam Oil Co., Ltd. only | Piedre Lumbre | Duval | 1 | 0 | 0 | — |
| Duval Ranch Sec. 96 O-4-11923 | Southwest Royalties, Inc. only | Petrox (Government Wells) | Duval | 1 | 0 | 0 | — |
| Duval Ranch Section 62 O-4-12060 | Dewbre, Jerry C., Trustee only | Wildcat | Duval | 1 | 0 | 0 | — |
| Duval Ranch Sec. 101 O-4-12227 | Killam Oil Co., Ltd. only | Brelum (Govt. Wells Sand) | Duval | 1 | 0 | 0 | — |
| Duval Ranch Sec. 63-291 O-4-418 | Man-Gas Transmission Company only | Casa Blanca | Duval | 6 | 0 | 0 | — |
| Duval Ranch Sec. #132 O-4-440 | Manges, Clinton only | Cedro Hill | Duval | 16 | 0 | 0 | — |
| Duval Ranch Sec. 49 O-4-843 | Manges, Clinton only | Forty-Nine | Duval | 2 | 0 | 0 | — |
| Duval Ranch Sec. 80 a/C #2 O-4-4588 | Manges, Clinton only | Seventy-Six, South | Duval | 2 | 0 | 0 | — |
| Duval Ranch Sec. 75 O-4-4508 | Killam Oil Co., Ltd. only | Seventy-Six, South | Duval | 7 | 0 | 0 | — |
| Duval Ranch Section 49 O-4-8897 | Manges, Clinton only | Forty Nine (Mirando 2380) | Duval | 1 | 0 | 0 | — |
| Duval Ranch Sec. 189 O-4-441 | Manges, Clinton only | Cedro Hill | Duval | 16 | 0 | 0 | — |