diff --git a/lib/class_builder.js b/lib/class_builder.js
index e3df1cd..4456697 100644
--- a/lib/class_builder.js
+++ b/lib/class_builder.js
@@ -542,7 +542,7 @@ function attachPropInit( prototype, properties, members, cid )
         // property/visibility object) internally (this will translate to
         // this.__inst from within a method), but only if we're on our final
         // object (not a parent)
-        if ( typeof parent_init !== 'function' )
+        if ( !inherit )
         {
             util.defineSecureProp( vis, '__inst', this );
         }