diff --git a/system/src/Grav/Common/GPM/Licenses.php b/system/src/Grav/Common/GPM/Licenses.php
index 9a8798595..0d01b6bf6 100644
--- a/system/src/Grav/Common/GPM/Licenses.php
+++ b/system/src/Grav/Common/GPM/Licenses.php
@@ -39,6 +39,10 @@ class Licenses
         $licenses = YamlFile::instance(self::getLicensePath());
         $data = $licenses->content();
 
+        if ($license && !self::validate($license)) {
+            return false;
+        }
+
         if (!is_string($license)) {
             if (isset($data['licenses'][$slug])) {
                 unset($data['licenses'][$slug]);