diff --git a/src/main/java/eu/dnetlib/repo/manager/service/utils/Converter.java b/src/main/java/eu/dnetlib/repo/manager/service/utils/Converter.java
index 7275f76..18f7f08 100644
--- a/src/main/java/eu/dnetlib/repo/manager/service/utils/Converter.java
+++ b/src/main/java/eu/dnetlib/repo/manager/service/utils/Converter.java
@@ -307,7 +307,7 @@ public class Converter {
        /* if( repositoryObject.get("aggregationHistory").toString().equals("[]") ||
                 repositoryObject.get("aggregationHistory")!= null)
             return null;*/
-       if(repositoryObject.get("aggregationHistory").toString().equals("null"))
+       if(repositoryObject.get("aggregationHistory").toString().equals("[]"))
            return null;
 
 
@@ -322,7 +322,7 @@ public class Converter {
     private static AggregationDetails jsonToAggregationDetails(JSONObject aggregationObject) throws JSONException {
 
         AggregationDetails aggregationDetails = new AggregationDetails();
-        
+
         aggregationDetails.setAggregationStage(aggregationObject.get("aggregationStage").toString());
         //aggregationDetails.setCollectionMode(aggregationObject.get("collectionMode").toString());
         aggregationDetails.setDate(convertStringToDate(aggregationObject.get("date").toString()));