diff --git a/webapp/src/edu/cornell/mannlib/vitro/webapp/ontology/update/KnowledgeBaseUpdater.java b/webapp/src/edu/cornell/mannlib/vitro/webapp/ontology/update/KnowledgeBaseUpdater.java
index 3e685ed1e..a64025294 100644
--- a/webapp/src/edu/cornell/mannlib/vitro/webapp/ontology/update/KnowledgeBaseUpdater.java
+++ b/webapp/src/edu/cornell/mannlib/vitro/webapp/ontology/update/KnowledgeBaseUpdater.java
@@ -346,7 +346,9 @@ public class KnowledgeBaseUpdater {
 	}
 	
 	public static boolean isUpdatableABoxGraph(String graphName) {
-	    return (!graphName.contains("tbox") && !graphName.contains("filegraph"));
+	    return (graphName != null && !graphName.contains("tbox") 
+	            && !graphName.contains("filegraph") 
+	            && !graphName.contains("x-arq:UnionGraph"));
 	}
 
 	/**
diff --git a/webapp/src/edu/cornell/mannlib/vitro/webapp/servlet/setup/UpdateKnowledgeBase.java b/webapp/src/edu/cornell/mannlib/vitro/webapp/servlet/setup/UpdateKnowledgeBase.java
index 0f739dd5d..8c8f53533 100644
--- a/webapp/src/edu/cornell/mannlib/vitro/webapp/servlet/setup/UpdateKnowledgeBase.java
+++ b/webapp/src/edu/cornell/mannlib/vitro/webapp/servlet/setup/UpdateKnowledgeBase.java
@@ -141,7 +141,7 @@ public class UpdateKnowledgeBase implements ServletContextListener {
 			KnowledgeBaseUpdater ontologyUpdater = new KnowledgeBaseUpdater(settings);
 			boolean requiredUpdate = ontologyUpdater.updateRequired(ctx);
 
-			if(!JenaDataSourceSetupBase.isFirstStartup()) {
+			if(requiredUpdate && !JenaDataSourceSetupBase.isFirstStartup()) {
     			try {
     			    ctx.setAttribute(KBM_REQURIED_AT_STARTUP, Boolean.TRUE);
     			    migrationChangesMade = ontologyUpdater.update(ctx);