diff --git a/spec/opensearch/client/unit/opensearch_client_spec.rb b/spec/opensearch/client/unit/opensearch_client_spec.rb
index 635185e51..c43290714 100644
--- a/spec/opensearch/client/unit/opensearch_client_spec.rb
+++ b/spec/opensearch/client/unit/opensearch_client_spec.rb
@@ -1,3 +1,12 @@
+# SPDX-License-Identifier: Apache-2.0
+#
+# The OpenSearch Contributors require contributions made to
+# this file be licensed under the Apache-2.0 license or a
+# compatible open source license.
+#
+# Modifications Copyright OpenSearch Contributors. See
+# GitHub history for details.
+
 require_relative '../../../spec_helper'
 
 describe 'OpenSearch::Client#respond_to_missing?' do