diff --git a/specification/compute/resource-manager/Microsoft.Compute/stable/2020-12-01/compute.json b/specification/compute/resource-manager/Microsoft.Compute/stable/2020-12-01/compute.json
index 9125b984da8d..a8f477466739 100644
--- a/specification/compute/resource-manager/Microsoft.Compute/stable/2020-12-01/compute.json
+++ b/specification/compute/resource-manager/Microsoft.Compute/stable/2020-12-01/compute.json
@@ -7835,7 +7835,7 @@
       },
       "allOf": [
         {
-          "$ref": "#/definitions/Resource"
+          "$ref": "#/definitions/SubResourceReadOnly"
         }
       ],
       "description": "Describes a Virtual Machine Extension."