diff --git a/osbase/event/etcd/etcd.go b/osbase/event/etcd/etcd.go
index 8cf2440..3d554f1 100644
--- a/osbase/event/etcd/etcd.go
+++ b/osbase/event/etcd/etcd.go
@@ -1,3 +1,6 @@
+// Copyright The Monogon Project Authors.
+// SPDX-License-Identifier: Apache-2.0
+
 package etcd
 
 import (
diff --git a/osbase/event/etcd/etcd_test.go b/osbase/event/etcd/etcd_test.go
index 5effa6e..a5cde20 100644
--- a/osbase/event/etcd/etcd_test.go
+++ b/osbase/event/etcd/etcd_test.go
@@ -1,3 +1,6 @@
+// Copyright The Monogon Project Authors.
+// SPDX-License-Identifier: Apache-2.0
+
 package etcd
 
 import (