diff --git a/datastore_server/source/java/ch/systemsx/cisd/etlserver/registrator/DataSetStorageAlgorithm.java b/datastore_server/source/java/ch/systemsx/cisd/etlserver/registrator/DataSetStorageAlgorithm.java
index 4205e1606d7d0ec9d47d9b3893c7d8bbe433cdd2..354fc3b46ce1171e5f130ef0b476e21d518b9b1f 100644
--- a/datastore_server/source/java/ch/systemsx/cisd/etlserver/registrator/DataSetStorageAlgorithm.java
+++ b/datastore_server/source/java/ch/systemsx/cisd/etlserver/registrator/DataSetStorageAlgorithm.java
@@ -48,7 +48,6 @@ import ch.systemsx.cisd.etlserver.TransferredDataSetHandler;
 import ch.systemsx.cisd.etlserver.validation.IDataSetValidator;
 import ch.systemsx.cisd.openbis.dss.generic.server.DataStoreService;
 import ch.systemsx.cisd.openbis.dss.generic.shared.dto.DataSetInformation;
-import ch.systemsx.cisd.openbis.generic.client.web.client.exception.UserFailureException;
 import ch.systemsx.cisd.openbis.generic.shared.basic.dto.DataSetType;
 import ch.systemsx.cisd.openbis.generic.shared.dto.NewExternalData;
 import ch.systemsx.cisd.openbis.generic.shared.dto.StorageFormat;
@@ -121,10 +120,7 @@ public class DataSetStorageAlgorithm<T extends DataSetInformation>
         this.storeRoot = storageProcessor.getStoreRootDirectory();
         this.dataSetType = registrationDetails.getDataSetType();
 
-        if (dataStoreStrategy.getKey() != DataStoreStrategyKey.IDENTIFIED)
-        {
-            throw new UserFailureException("Data set must be associated with an experiment ");
-        }
+        assert dataStoreStrategy.getKey() == DataStoreStrategyKey.IDENTIFIED : "Data set must be associated with an experiment ";
 
         dataSetValidator.assertValidDataSet(dataSetType, incomingDataSetFile);