diff --git a/src/MessageInterface.php b/src/MessageInterface.php
index dd46e5e..c4ddade 100644
--- a/src/MessageInterface.php
+++ b/src/MessageInterface.php
@@ -37,6 +37,7 @@ public function getProtocolVersion();
      *
      * @param string $version HTTP protocol version
      * @return static
+     * @throws \InvalidArgumentException When the protocol version is not "1.0" or "1.1"
      */
     public function withProtocolVersion($version);