diff --git a/README.md b/README.md
index edce81f11..3c555838b 100644
--- a/README.md
+++ b/README.md
@@ -21,7 +21,9 @@ font will be at the top level.
 
 Emoji fonts (under the fonts subdirectory) are under the
 [SIL Open Font License, version 1.1](fonts/LICENSE).<br/>
-Tools are under the [Apache license, version 2.0](./LICENSE).
+Tools and most image resources are under the [Apache license, version 2.0](./LICENSE).
+Flag images under third_party/region-flags are in the public domain or
+otherwise exempt from copyright ([more info](third_party/region-flags/LICENSE)).
 
 ## Contributing