diff --git a/facho/fe/fe.py b/facho/fe/fe.py
index cce27f3..5c9a10c 100644
--- a/facho/fe/fe.py
+++ b/facho/fe/fe.py
@@ -32,6 +32,7 @@ NAMESPACES = {
     'xsi': 'http://www.w3.org/2001/XMLSchema-instance',
     'xades': 'http://uri.etsi.org/01903/v1.3.2#',
     'ds': 'http://www.w3.org/2000/09/xmldsig#',
+    'sig': 'http://www.w3.org/2000/09/xmldsig#',
 }