diff --git a/core/dbobject.class.php b/core/dbobject.class.php
index a1b0702065..ef09e7e6ab 100644
--- a/core/dbobject.class.php
+++ b/core/dbobject.class.php
@@ -1670,6 +1670,7 @@ abstract class DBObject implements iDisplay
 	 *
 	 * @return integer the binary combination of flags for the given attribute in the given state of the object.
 	 * Values can be one of the OPT_ATT_HIDDEN, OPT_ATT_READONLY, OPT_ATT_MANDATORY, ... (see define in metamodel.class.php)
+	 * Concat multiple values using the "|" operator.
      *
 	 * @throws \CoreException
 	 *