diff --git a/aeon.ttl b/aeon.ttl
index 6b9a0cc..c33e7a9 100644
--- a/aeon.ttl
+++ b/aeon.ttl
@@ -2577,19 +2577,6 @@ obo:OBI_0100026 rdf:type owl:Class ;
                 rdfs:label "organism"@en .
 
 
-###  http://www.w3.org/2004/02/skos/core#Concept
-skos:Concept rdf:type owl:Class ;
-             obo:IAO_0000115 """A SKOS concept can be viewed as an idea or notion; a unit of thought. However, what constitutes a unit of thought is subjective, and this definition is meant to be suggestive, rather than restrictive.
-
-The notion of a SKOS concept is useful when describing the conceptual or intellectual structure of a knowledge organization system, and when referring to specific ideas or meanings established within a KOS.
-
-Note that, because SKOS is designed to be a vehicle for representing semi-formal KOS, such as thesauri and classification schemes, a certain amount of flexibility has been built in to the formal definition of this class.
-
-See the [SKOS-PRIMER] for more examples of identifying and describing SKOS concepts."""@en ;
-             obo:IAO_0000412 "https://www.w3.org/2009/08/skos-reference/skos.html#Concept" ;
-             rdfs:label "Concept" .
-
-
 ###  https://github.com/tibonto/aeon#AEON_0000001
 aeon:AEON_0000001 rdf:type owl:Class ;
                   owl:equivalentClass [ owl:intersectionOf ( obo:OBI_0000011