diff --git a/atrcopy/_metadata.py b/atrcopy/_metadata.py
index 64982a8..30b1606 100644
--- a/atrcopy/_metadata.py
+++ b/atrcopy/_metadata.py
@@ -1,4 +1,4 @@
-__version__ = "4.0"
+__version__ = "4.0rc1"
 __author__ = "Rob McMullen"
 __author_email__ = "feedback@playermissile.com"
 __url__ = "https://github.com/robmcmullen/atrcopy"