diff --git a/themekey_base.inc b/themekey_base.inc
index 2013af6..9d4ff90 100644
--- a/themekey_base.inc
+++ b/themekey_base.inc
@@ -327,7 +327,13 @@ function themekey_match_condition($condition, &$parameters) {
     }
 
     if ('drupal:path' == $condition->property) {
-      return themekey_match_path($condition, $parameters);
+      $match_path = themekey_match_path($condition, $parameters);
+      if ($condition->operator == '=') {
+        return $match_path;
+       }
+       // only '=' and '!' are allowed
+       // @see themekey_validator_drupal_path()
+       return !$match_path;
     }
 
     $value = themekey_property_value($parameters, $condition->property);