diff --git a/docs/pon-requirements/olt-states.block b/docs/pon-requirements/olt-states.block
index 8e2c71d..b5d5820 100644
--- a/docs/pon-requirements/olt-states.block
+++ b/docs/pon-requirements/olt-states.block
@@ -1,3 +1,17 @@
+# 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.
+
 blockdiag {
 
   // States
diff --git a/docs/pon-requirements/reference-inband.block b/docs/pon-requirements/reference-inband.block
index 95195e9..30cafb7 100644
--- a/docs/pon-requirements/reference-inband.block
+++ b/docs/pon-requirements/reference-inband.block
@@ -1,3 +1,17 @@
+# 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.
+
 blockdiag {
 
     //orientation = portrait;
diff --git a/docs/pon-requirements/reference-internal.block b/docs/pon-requirements/reference-internal.block
index 4b33854..878fde5 100644
--- a/docs/pon-requirements/reference-internal.block
+++ b/docs/pon-requirements/reference-internal.block
@@ -1,3 +1,17 @@
+# 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.
+
 blockdiag {
 
     //orientation = portrait;