X0508 4 2025-11-25 0001172358 DORCHESTER MINERALS, L.P. DMLP 0001203847 VAUGHN ROBERT C 3838 OAK LAWN AVENUE SUITE 710 DALLAS TX 75219 1 0 Common Units 2025-11-25 4 P 0 4263 21.41 A 20000 D Common Units 2025-11-25 4 P 0 352 21.39 A 20352 D Common Units 500000 I . Common Units 20000.686 I . These common units are held by Mr. Vaughn in his individual name, IRA or Keogh Plan. These common units are held by Vaughn Petroleum (DMLP), LLC. Mr. Vaughn and his spouse are the only unit holders of Vaughn Petroleum (DMLP), LLC. These common units are held by Empire Partners, Ltd. Mr. Vaughn is the President of Empire (GP), Inc., the general partner of Empire Partners, Ltd. Mr. Vaughn and his spouse are the shareholders of Empire (GP), Inc. Mr. Vaughn disclaims beneficial ownership of such common units, except to the extent of his pecuniary interest therein. /s/ Robert C. Vaughn 2025-11-28