diff --git a/EventOntology.ttl b/EventOntology.ttl
index f095959..5739f2e 100644
--- a/EventOntology.ttl
+++ b/EventOntology.ttl
@@ -1259,9 +1259,13 @@ cco:BrillianceFrequency rdf:type owl:Class ;
 
 ###  http://www.ontologyrepository.com/CommonCoreOntologies/Cause
 cco:Cause rdf:type owl:Class ;
-          owl:equivalentClass [ rdf:type owl:Restriction ;
-                                owl:onProperty cco:is_cause_of ;
-                                owl:someValuesFrom obo:BFO_0000003
+          owl:equivalentClass [ owl:intersectionOf ( obo:BFO_0000015
+                                                     [ rdf:type owl:Restriction ;
+                                                       owl:onProperty cco:is_cause_of ;
+                                                       owl:someValuesFrom obo:BFO_0000003
+                                                     ]
+                                                   ) ;
+                                rdf:type owl:Class
                               ] ;
           rdfs:subClassOf obo:BFO_0000015 ;
           cco:definition "A Process that is the cause of or one of the causes of some other Process."@en ;
@@ -1450,9 +1454,13 @@ cco:DeltaV rdf:type owl:Class ;
 
 ###  http://www.ontologyrepository.com/CommonCoreOntologies/Effect
 cco:Effect rdf:type owl:Class ;
-           owl:equivalentClass [ rdf:type owl:Restriction ;
-                                 owl:onProperty cco:caused_by ;
-                                 owl:someValuesFrom obo:BFO_0000003
+           owl:equivalentClass [ owl:intersectionOf ( obo:BFO_0000015
+                                                      [ rdf:type owl:Restriction ;
+                                                        owl:onProperty cco:caused_by ;
+                                                        owl:someValuesFrom obo:BFO_0000003
+                                                      ]
+                                                    ) ;
+                                 rdf:type owl:Class
                                ] ;
            rdfs:subClassOf obo:BFO_0000015 ;
            cco:alternative_label "Consequence"@en ;