diff --git a/project.config b/project.config
index a1a3fb9..5044e44 100644
--- a/project.config
+++ b/project.config
@@ -107,5 +107,6 @@
 	submit = group Registered Users
 	forgeAuthor = group ldap/OSM_Admin
 	forgeCommitter = group ldap/OSM_Admin
+	exclusiveGroupPermissions = forgeAuthor forgeCommitter
 [plugin "its-bugzilla"]
 	enabled = true