diff --git a/pymongo/__init__.py b/pymongo/__init__.py
index 406984e82..46e2081d5 100644
--- a/pymongo/__init__.py
+++ b/pymongo/__init__.py
@@ -99,7 +99,7 @@ See https://docs.mongodb.com/manual/tutorial/manage-the-database-profiler
    Deprecated
 """
 
-version_tuple = (3, 12, 3)
+version_tuple = (3, 12, 4, '.dev0')
 
 def get_version_string():
     if isinstance(version_tuple[-1], str):
diff --git a/setup.py b/setup.py
index b1715f31e..5248176f8 100755
--- a/setup.py
+++ b/setup.py
@@ -43,7 +43,7 @@ except ImportError:
     except ImportError:
         _HAVE_SPHINX = False
 
-version = "3.12.3"
+version = "3.12.4.dev0"
 
 f = open("README.rst")
 try: