diff --git a/library/init/data/nat/bitwise.lean b/library/init/data/nat/bitwise.lean
index ccfadaa3d5..b5811df056 100644
--- a/library/init/data/nat/bitwise.lean
+++ b/library/init/data/nat/bitwise.lean
@@ -1,5 +1,5 @@
 /-
-Copyright (c) 2014 Microsoft Corporation. All rights reserved.
+Copyright (c) 2017 Microsoft Corporation. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Author: Mario Carneiro
 -/