diff --git a/src/grpc_client/main.py b/src/grpc_client/main.py
index b3e29b1..90ecc0b 100644
--- a/src/grpc_client/main.py
+++ b/src/grpc_client/main.py
@@ -1,3 +1,19 @@
+
+# Copyright 2017-present Open Networking Foundation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
 import functools
 from xosapi.xos_grpc_client import SecureClient, InsecureClient
 from twisted.internet import defer