diff --git a/datetime.py b/datetime.py
index f41aecd70511dfe0a0c261d453de0892065945d7..435b3bc7cf1744e25674de7e2d1629d4fd1052b3 100644
--- a/datetime.py
+++ b/datetime.py
@@ -1,3 +1,18 @@
+# Copyright © 2016 Bruce Cowan <bruce@bcowan.eu>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program 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 for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
 from datetime import datetime
 
 from errbot import BotPlugin, botcmd