diff --git a/notebook/_version.py b/notebook/_version.py
index f4e701369..361763de5 100644
--- a/notebook/_version.py
+++ b/notebook/_version.py
@@ -9,5 +9,5 @@ store the current version info of the notebook.
 
 # Next beta/alpha/rc release: The version number for beta is X.Y.ZbN **without dots**. 
 
-version_info = (5, 2, 1)
+version_info = (5, 3, 0, ".dev0")
 __version__ = '.'.join(map(str, version_info[:3])) + ''.join(version_info[3:])