diff --git a/pisi-spec.rng b/pisi-spec.rng
index 46de3037..1711caf1 100644
--- a/pisi-spec.rng
+++ b/pisi-spec.rng
@@ -203,6 +203,7 @@
                 <value>BL</value>
                 <value>BSD</value>
                 <value>BSD-2</value>
+                <value>BSD-3</value>
                 <value>BWidget</value>
                 <value>BZIP2</value>
                 <value>Babylon</value>