diff --git a/google/appengine.go b/google/appengine.go
index 4a99ffc..ea18871 100644
--- a/google/appengine.go
+++ b/google/appengine.go
@@ -1,3 +1,7 @@
+// Copyright 2014 The oauth2 Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
 // +build appengine
 
 package google
diff --git a/google/appenginevm.go b/google/appenginevm.go
index ea9acc3..32c017a 100644
--- a/google/appenginevm.go
+++ b/google/appenginevm.go
@@ -1,3 +1,7 @@
+// Copyright 2014 The oauth2 Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
 // +build !appengine
 
 package google
diff --git a/google/example_test.go b/google/example_test.go
index 380bd47..d7a3be4 100644
--- a/google/example_test.go
+++ b/google/example_test.go
@@ -1,3 +1,7 @@
+// Copyright 2014 The oauth2 Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
 package google_test
 
 import (