diff --git a/schemas/data-ingress/mq-file-update.json b/schemas/data-ingress/mq-file-update.json
index 4bad02f..2856f54 100644
--- a/schemas/data-ingress/mq-file-update.json
+++ b/schemas/data-ingress/mq-file-update.json
@@ -8,6 +8,10 @@
             "type": "string",
             "description": "Name of the service submitting the update"
         },
+        "service_id": {
+            "type": "string",
+            "description": "ID of the service sending the message - usually a hostname"
+        },
         "data_type": {
             "type": "string",
             "enum": ["file"],
@@ -38,6 +42,6 @@
             "additionalProperties": false
         }
     },
-    "required": ["service_name", "data_type", "sent_timestamp", "data_kind", "payload"],
+    "required": ["service_name", "service_id", "data_type", "sent_timestamp", "data_kind", "payload"],
     "additionalProperties": false
 }
\ No newline at end of file