diff --git a/core/Api/Request.class.php b/core/Api/Request.class.php
index acdd7a9..fda90c0 100644
--- a/core/Api/Request.class.php
+++ b/core/Api/Request.class.php
@@ -129,7 +129,7 @@ class Request {
         $this->lastError = 'You are not logged in.';
         header('HTTP 1.1 401 Unauthorized');
         return false;
-      } else if(!empty($this->requiredGroup) && !empty(array_intersect($this->requiredGroup, $this->user->getGroups()))) {
+      } else if(!empty($this->requiredGroup) && empty(array_intersect($this->requiredGroup, $this->user->getGroups()))) {
         $this->lastError = "Insufficient permissions. Required group: "
           . implode(", ", array_map(function ($group) { return GroupName($group); }, $this->requiredGroup));
         header('HTTP 1.1 401 Unauthorized');