diff --git a/Makefile b/Makefile
index 7729507..dd78f86 100644
--- a/Makefile
+++ b/Makefile
@@ -1,3 +1,17 @@
+# Copyright 2018 Google LLC
+#
+# 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
+#
+#     https://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.
+
 # Set path to prebuilts used in the build.
 UNNAME_S := $(shell uname -s | tr '[:upper:]' '[:lower:]')
 PREBUILTS := $(PWD)/prebuilts/$(UNNAME_S)-x64