diff --git a/user_guide_src/source/changelogs/v4.5.6.rst b/user_guide_src/source/changelogs/v4.5.6.rst
index 33e3e5a1a0ab..e9e7d224d014 100644
--- a/user_guide_src/source/changelogs/v4.5.6.rst
+++ b/user_guide_src/source/changelogs/v4.5.6.rst
@@ -22,6 +22,9 @@ Message Changes
 Changes
 *******
 
+- **Validation:** Rule ``is_unique`` and ``is_not_unique`` now accept an optional
+ ``dbGroup`` as parameter.
+
 ************
 Deprecations
 ************