diff --git a/docs/messaging.rst b/docs/messaging.rst
index ec8efd99f..7c533a7de 100644
--- a/docs/messaging.rst
+++ b/docs/messaging.rst
@@ -21,7 +21,7 @@ Versioning
 
 The Jupyter message specification is versioned independently of the packages
 that use it.
-The current version of the specification is 5.2.
+The current version of the specification is 5.3.
 
 .. note::
    *New in* and *Changed in* messages in this document refer to versions of the
diff --git a/jupyter_client/_version.py b/jupyter_client/_version.py
index 90dd2e93e..7f96345ae 100644
--- a/jupyter_client/_version.py
+++ b/jupyter_client/_version.py
@@ -1,5 +1,5 @@
 version_info = (5, 1, 0)
 __version__ = '.'.join(map(str, version_info))
 
-protocol_version_info = (5, 2)
+protocol_version_info = (5, 3)
 protocol_version = "%i.%i" % protocol_version_info