diff --git a/index.php b/index.php
index 388c8e4b4..66858a52c 100644
--- a/index.php
+++ b/index.php
@@ -39,7 +39,7 @@ function pr($name, $url, $comma) {
 <td valign=top>
 <ul>
 
-<li> Full MPI-4.1 standards conformance
+<li> Full MPI-3.1 standards conformance, with many elements from MPI-4.0
 <li> Thread safety and concurrency
 <li> Dynamic process spawning
 <li> Network and process fault tolerance