diff --git a/src/ontologies/Conceptual/Conceptual.thy b/src/ontologies/Conceptual/Conceptual.thy
index da79817..fb9c6e5 100644
--- a/src/ontologies/Conceptual/Conceptual.thy
+++ b/src/ontologies/Conceptual/Conceptual.thy
@@ -220,4 +220,6 @@ close_monitor*[test_monitor_M2]
 
 close_monitor*[test_monitor_M]
 
+declare[[free_class_in_monitor_checking = false]]
+
 end
diff --git a/src/tests/Attributes.thy b/src/tests/Attributes.thy
index 762bccf..73266b1 100644
--- a/src/tests/Attributes.thy
+++ b/src/tests/Attributes.thy
@@ -240,6 +240,8 @@ text*[testRejected2::figure_group, caption="''figures/A.png''"]
 
 close_monitor*[figs1]  
 
+declare[[free_class_in_monitor_checking = false]]
+
 text\<open>Resulting trace of figs1 as ML antiquotation: \<close>
 ML  \<open>@{trace_attribute figs1}\<close>
 text\<open>Resulting trace of figs as text antiquotation:\<close>