diff --git a/src/Factory/JWKFactory.php b/src/Factory/JWKFactory.php
index b5682253..9d3a93ec 100644
--- a/src/Factory/JWKFactory.php
+++ b/src/Factory/JWKFactory.php
@@ -56,6 +56,13 @@ private static function convertDecToBin($value)
         return hex2bin($adapter->decHex($value));
     }
 
+    /**
+     * @param string $curve
+     *
+     * @throws \InvalidArgumentException
+     *
+     * @return string
+     */
     private static function getNistName($curve)
     {
         switch ($curve) {