diff --git a/PPI/AnnotationRouter.hh b/PPI/AnnotationRouter.hh
index 0787cbbd0c16a4b3575ad91a93672849c33133d8..7eada36a6ee50828054c4bde55687313a5159060 100644
--- a/PPI/AnnotationRouter.hh
+++ b/PPI/AnnotationRouter.hh
@@ -48,9 +48,10 @@ namespace module {
 
         The \a AnnotationType template parameter defines the routing key. This annotation must
         support the following operations:
-        \li Comparison with '<'
-        \li Copy-construction
-        \li Output streaming to an ostream via '<<'
+        \li Comparison with '<' (\c LessThanCompatable concept)
+        \li Copy construction and copy assignment (\c Copyable und \c Assignable concepts)
+            (e.g. via compiler synthesized copy constructor and assignment operator)
+        \li Output streaming to an ostream via '\c <<' (\c OutputStreamable concept)
 
         The following annotation can be used to route the packets according to a mac address.
         \code