diff --git a/versionmanager/tenvlib/examples/dtofuver/ex1.go b/versionmanager/tenvlib/examples/dtofuver/ex1.go
index 17fe3058..368a8bd0 100644
--- a/versionmanager/tenvlib/examples/dtofuver/ex1.go
+++ b/versionmanager/tenvlib/examples/dtofuver/ex1.go
@@ -1,3 +1,21 @@
+/*
+ *
+ * Copyright 2024 tofuutils authors.
+ *
+ * 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.
+ *
+ */
+
 package main
 
 import (
diff --git a/versionmanager/tenvlib/examples/ltfver/ex2.go b/versionmanager/tenvlib/examples/ltfver/ex2.go
index 69eb6ced..ccbd0b85 100644
--- a/versionmanager/tenvlib/examples/ltfver/ex2.go
+++ b/versionmanager/tenvlib/examples/ltfver/ex2.go
@@ -1,3 +1,21 @@
+/*
+ *
+ * Copyright 2024 tofuutils authors.
+ *
+ * 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.
+ *
+ */
+
 package main
 
 import (