diff --git a/rdf/tbox/filegraph/classes-additional.owl b/rdf/tbox/filegraph/classes-additional.owl
index 864b97a1..70b15bee 100644
--- a/rdf/tbox/filegraph/classes-additional.owl
+++ b/rdf/tbox/filegraph/classes-additional.owl
@@ -866,6 +866,12 @@
                 <owl:allValuesFrom rdf:resource="http://xmlns.com/foaf/0.1/Organization"/>
             </owl:Restriction>
         </rdfs:subClassOf>
+        <rdfs:subClassOf>
+            <owl:Restriction>
+                <owl:onProperty rdf:resource="http://vivoweb.org/ontology/core#dateTimeInterval"/>
+                <owl:allValuesFrom rdf:resource="http://vivoweb.org/ontology/core#DateTimeInterval"/>
+            </owl:Restriction>
+        </rdfs:subClassOf>
     </owl:Class>