diff --git a/models/Shipyard.json b/models/Shipyard.json
index d7762f0..dd27552 100644
--- a/models/Shipyard.json
+++ b/models/Shipyard.json
@@ -16,7 +16,10 @@
           "type": {
             "$ref": "./ShipType.json"
           }
-        }
+        },
+        "required": [
+          "type"
+        ]
       }
     },
     "transactions": {