diff --git a/cif_ed.dic b/cif_ed.dic
index d6c1426..d3adeb3 100644
--- a/cif_ed.dic
+++ b/cif_ed.dic
@@ -1,4 +1,5 @@
 #\#CIF_2.0
+# SPDX-License-Identifier: CC-BY-4.0
 ##############################################################################
 #                                                                            #
 #                    CIF Electron Diffraction Dictionary                     #
@@ -17,6 +18,7 @@ data_CIF_ED
     _dictionary.uri
          https://raw.githubusercontent.com/COMCIFS/cif_ed/main/cif_ed.dic
     _dictionary.ddl_conformance  4.2.0
+    _dictionary.licensing_SPDX   CC-BY-4.0
     _dictionary.namespace        CifCore
     _description.text
 ;
diff --git a/draft_new_items.dic b/draft_new_items.dic
index f00b8fb..b5844f4 100644
--- a/draft_new_items.dic
+++ b/draft_new_items.dic
@@ -1,4 +1,5 @@
 #\#CIF_2.0
+# SPDX-License-Identifier: CC-BY-4.0
 ##############################################################################
 # Some possible additions to the initial cif_ed.dic for electron diffraction.#
 # These are tentative new items to extend cif_img.dic for raw data.          #
@@ -11,8 +12,9 @@ data_DRAFT_NEW_ITEMS
     _dictionary.version          0.0.10
     _dictionary.date             2025-03-24
     _dictionary.uri
-      https://raw.githubusercontent.com/COMCIFS/cif_ed/1.0.0/draft_new_items.dic
+      https://raw.githubusercontent.com/COMCIFS/cif_ed/main/draft_new_items.dic
     _dictionary.ddl_conformance  4.2.0
+    _dictionary.licensing_SPDX   CC-BY-4.0
     _dictionary.namespace        CifCore
     _description.text
 ;