diff --git a/engine-contract.json b/engine-contract.json
index b0c8908..03e6457 100644
--- a/engine-contract.json
+++ b/engine-contract.json
@@ -139,13 +139,21 @@
       "name": "DiagramLayout::Route",
       "kind": "metadata",
       "attributes": [
-        "points"
+        "points",
+        "general"
       ],
       "migratorEmitted": true,
       "consumers": [
         "internal/semantic/semantics/layout.go"
       ]
     },
+    {
+      "name": "DiagramLayout::Route::general",
+      "kind": "element",
+      "consumers": [
+        "internal/semantic/semantics/layout.go"
+      ]
+    },
     {
       "name": "DiagramLayout::Route::points",
       "kind": "element",
diff --git a/libraries/DiagramLayout.sysml b/libraries/DiagramLayout.sysml
index fdf0b1a..06b9641 100644
--- a/libraries/DiagramLayout.sysml
+++ b/libraries/DiagramLayout.sysml
@@ -17,8 +17,13 @@ library package DiagramLayout {
 
     metadata def Route {
         doc /* The waypoints a connection, transition, succession or flow is
-             * drawn through, in order, flattened as x0, y0, x1, y1, ... */
+             * drawn through, in order, flattened as x0, y0, x1, y1, ...
+             * A specialization has no element of its own to annotate: its
+             * Route is stated about the specific element and names the
+             * general it is drawn to, `ref :>> general : Sup;`, one Route
+             * per general. */
         attribute points : ScalarValues::Real[0..*] ordered nonunique;
+        ref general : Base::Anything[0..1];
     }
 
     metadata def Canvas {