diff --git a/src/test/examples/classmerging/NoHorizontalClassMerging.java b/src/test/examples/classmerging/NoHorizontalClassMerging.java
new file mode 100644
index 0000000..3b7a831
--- /dev/null
+++ b/src/test/examples/classmerging/NoHorizontalClassMerging.java
@@ -0,0 +1,10 @@
+// Copyright (c) 2021, the R8 project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+package classmerging;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Target;
+
+@Target({ElementType.TYPE})
+public @interface NoHorizontalClassMerging {}