diff --git a/enanomapper.owl b/enanomapper.owl
index cdcac3c5..9ee6608a 100644
--- a/enanomapper.owl
+++ b/enanomapper.owl
@@ -19,6 +19,7 @@
      xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
     <owl:Ontology rdf:about="http://purl.enanomapper.org/onto/enanomapper.owl">
         <dc:contributor>Nina Jeliazkova</dc:contributor>
+        <owl:versionInfo>1</owl:versionInfo>
         <dc:license>CC-BY 3.0 https://creativecommons.org/licenses/by/3.0/</dc:license>
         <dc:contributor>Janna Hastings</dc:contributor>
         <dc:contributor>Egon Willighagen</dc:contributor>