diff --git a/IPython/html/static/notebook/js/widgets/widget.js b/IPython/html/static/notebook/js/widgets/widget.js
index 205288a..2d6188b 100644
--- a/IPython/html/static/notebook/js/widgets/widget.js
+++ b/IPython/html/static/notebook/js/widgets/widget.js
@@ -149,7 +149,7 @@ function(widget_manager, underscore, backbone){
                             }
                         }
 
-                        var data = {method: 'backbone', sync_method: method, sync_data: send_json};
+                        var data = {method: 'backbone', sync_data: send_json};
                         this.comm.send(data, options.callbacks);
                         this.pending_msgs++;
                     }