diff --git a/bob/devtools/release.py b/bob/devtools/release.py
index 6c3b6a0954bb08cea79bc64b7ff8efc11dfddf0f..ca153083b36a1748578e453498cfc3d5adc60334 100644
--- a/bob/devtools/release.py
+++ b/bob/devtools/release.py
@@ -138,6 +138,8 @@ def get_latest_tag_name(gitpkg):
         for tag in latest_tags
         if StrictVersion.version_re.match(tag.name[1:])
     ]
+    if not tag_names: # no tags wee found.
+        return None
     # sort them correctly according to each subversion number
     tag_names.sort(key=StrictVersion)
     # take the last one, as it is the latest tag in the sorted tags