diff --git a/keymaster/aidl/Android.bp b/keymaster/aidl/Android.bp
index 56a3ca9..5206721 100644
--- a/keymaster/aidl/Android.bp
+++ b/keymaster/aidl/Android.bp
@@ -20,3 +20,12 @@
         "2",
     ],
 }
+
+// This is a reminder that the next version of keymaster should be frozen at
+// version "5" to avoid confusion with other versions of this interface.
+cc_library {
+    name: "android.hardware.keymaster-V3-java",
+}
+cc_library {
+    name: "android.hardware.keymaster-V4-java",
+}