diff --git a/COPYING.txt b/COPYING.txt
index 705db57..ec52dd2 100644
--- a/COPYING.txt
+++ b/COPYING.txt
@@ -1,6 +1,9 @@
 Copyright 2008, Google Inc.
 All rights reserved.
 
+Changes from Google release:
+Copyright 2012-2014, OpenX.
+
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions are
 met: