diff --git a/index.html b/index.html
index 39ac46b..8bc679d 100644
--- a/index.html
+++ b/index.html
@@ -1029,6 +1029,7 @@ <h2>
         interface GeolocationPosition {
           readonly attribute GeolocationCoordinates coords;
           readonly attribute EpochTimeStamp timestamp;
+          [Default] object toJSON(); 
         };
       </pre>
       <section>
@@ -1110,6 +1111,7 @@ <h2>
           readonly attribute double? altitudeAccuracy;
           readonly attribute double? heading;
           readonly attribute double? speed;
+          [Default] object toJSON();
         };
       </pre>
       <section>