diff --git a/misc/errorcodes.md b/misc/errorcodes.md
index 04bd64c..0d24e56 100644
--- a/misc/errorcodes.md
+++ b/misc/errorcodes.md
@@ -87,6 +87,7 @@
 814: "Unknown rewrite operation"
 815: "Rewrite expects source"
 820: "Dates require value fields"
+821: "Reference is missing"
 830: "Filter was empty"
 831: "Filter is not wrappable"
 832: "Filter operation is invalid"
diff --git a/src/main/java/de/ids_mannheim/korap/util/StatusCodes.java b/src/main/java/de/ids_mannheim/korap/util/StatusCodes.java
index a9c9adf..0560af1 100644
--- a/src/main/java/de/ids_mannheim/korap/util/StatusCodes.java
+++ b/src/main/java/de/ids_mannheim/korap/util/StatusCodes.java
@@ -40,7 +40,6 @@
     public static final int MISSING_RELATION_NODE = 717;
     public static final int MISSING_RELATION_TERM = 718;
     public static final int INVALID_QUERY = 719;
-    public static final int MISSING_VC_REFERENCE = 720;
     
     public static final int INVALID_MATCH_ID = 730;
     public static final int MISSING_KEY = 740;
@@ -71,6 +70,7 @@
     public static final int MISSING_SOURCE = 815;
     public static final int MISSING_ID = 816;
     public static final int MISSING_VALUE = 820;
+    public static final int MISSING_VC_REFERENCE = 821;
     public static final int EMPTY_FILTER = 830;
     public static final int UNWRAPPABLE_FILTER = 831;
     public static final int INVALID_FILTER_OPERATION = 832;