diff --git sites/all/themes/versatile/plugins/styles/versatile_tag/versatile_tag.inc sites/all/themes/versatile/plugins/styles/versatile_tag/versatile_tag.inc
index 12fd9e0..22052d8 100644
--- sites/all/themes/versatile/plugins/styles/versatile_tag/versatile_tag.inc
+++ sites/all/themes/versatile/plugins/styles/versatile_tag/versatile_tag.inc
@@ -23,7 +23,7 @@ function theme_versatile_tag_style_render_pane($vars) {
   $output = '';
 
   if ($content->type == 'block') {
-    $content->title = $content->subject;
+    $content->title = isset($content->subject) ? $content->subject : NULL;
   }
 
   if (empty($settings['content_tag'])) {