diff --git a/lib/types/subdocument.js b/lib/types/subdocument.js
index 521237aee72..b015a091cf3 100644
--- a/lib/types/subdocument.js
+++ b/lib/types/subdocument.js
@@ -48,6 +48,8 @@ function Subdocument(value, fields, parent, skipId, options) {
         }
       }
     }
+
+    delete options.priorDoc;
   }
 }