diff --git a/web/gui/src/main/webapp/app/fw/widget/button.css b/web/gui/src/main/webapp/app/fw/widget/button.css
index 9ae0359..26540af 100644
--- a/web/gui/src/main/webapp/app/fw/widget/button.css
+++ b/web/gui/src/main/webapp/app/fw/widget/button.css
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 Open Networking Laboratory
+ * Copyright 2015-present Open Networking Laboratory
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.