diff --git a/battery_status_led.sh b/battery_status_led.sh
index 9164948..b493a60 100755
--- a/battery_status_led.sh
+++ b/battery_status_led.sh
@@ -1,5 +1,15 @@
 #!/bin/bash
 
+# Copyright 2018 Denes Matetelki
+
+# This file is part of battery_status_led.
+
+# battery_status_led is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License v3 as published by the Free Software Foundation.
+
+# battery_status_led is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License v3 for more details.
+
+# You should have received a copy of the GNU General Public License v3 along with battery_status_led. If not, see https://www.gnu.org/licenses/gpl-3.0.html.
+
 # limits in percentages
 LOW=10 # flip LED every 2s
 CRIT=5 # flip led every 0.5s