diff --git a/test/erl/src/stress_server.erl b/test/erl/src/stress_server.erl
index d82f940..35fff06 100644
--- a/test/erl/src/stress_server.erl
+++ b/test/erl/src/stress_server.erl
@@ -1,3 +1,22 @@
+%%
+%% Licensed to the Apache Software Foundation (ASF) under one
+%% or more contributor license agreements. See the NOTICE file
+%% distributed with this work for additional information
+%% regarding copyright ownership. The ASF licenses this file
+%% to you 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.
+%%
+
 -module(stress_server).
 
 
diff --git a/test/erl/src/test_disklog.erl b/test/erl/src/test_disklog.erl
index 3036682..7b0be72 100644
--- a/test/erl/src/test_disklog.erl
+++ b/test/erl/src/test_disklog.erl
@@ -1,3 +1,22 @@
+%%
+%% Licensed to the Apache Software Foundation (ASF) under one
+%% or more contributor license agreements. See the NOTICE file
+%% distributed with this work for additional information
+%% regarding copyright ownership. The ASF licenses this file
+%% to you 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.
+%%
+
 -module(test_disklog).
 
 -compile(export_all).
diff --git a/test/erl/src/test_membuffer.erl b/test/erl/src/test_membuffer.erl
index 66f7f6c..7bd23a0 100644
--- a/test/erl/src/test_membuffer.erl
+++ b/test/erl/src/test_membuffer.erl
@@ -1,3 +1,22 @@
+%%
+%% Licensed to the Apache Software Foundation (ASF) under one
+%% or more contributor license agreements. See the NOTICE file
+%% distributed with this work for additional information
+%% regarding copyright ownership. The ASF licenses this file
+%% to you 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.
+%%
+
 -module(test_membuffer).
 -export([t/0]).
 
diff --git a/test/erl/src/test_server.erl b/test/erl/src/test_server.erl
index 45143b7..cd439cc 100644
--- a/test/erl/src/test_server.erl
+++ b/test/erl/src/test_server.erl
@@ -1,3 +1,22 @@
+%%
+%% Licensed to the Apache Software Foundation (ASF) under one
+%% or more contributor license agreements. See the NOTICE file
+%% distributed with this work for additional information
+%% regarding copyright ownership. The ASF licenses this file
+%% to you 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.
+%%
+
 -module(test_server).
 
 -export([start_link/1, handle_function/2]).