diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 3ad9e566a5d93..154c5e6e58108 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -246,6 +246,10 @@ Improvements to Clang's diagnostics
   decorated with the ``alloc_size`` attribute don't allocate enough space for
   the target pointer type.
 
+- The :doc:`ThreadSafetyAnalysis` attributes ``ACQUIRED_BEFORE(...)`` and
+  ``ACQUIRED_AFTER(...)`` have been moved to the stable feature set and no
+  longer require ``-Wthread-safety-beta`` to be used.
+
 Improvements to Clang's time-trace
 ----------------------------------