diff --git a/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/business/bo/EntityTypePropertyTypeBO.java b/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/business/bo/EntityTypePropertyTypeBO.java
index c27e8af2025dd9c9e27764bcb4f3967535017a03..1271faa227c01dc84100810a70e888b23c0d882e 100644
--- a/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/business/bo/EntityTypePropertyTypeBO.java
+++ b/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/business/bo/EntityTypePropertyTypeBO.java
@@ -161,12 +161,6 @@ public class EntityTypePropertyTypeBO extends AbstractBusinessObject implements
         }
     }
 
-    private void updateEntityModificationTimestamps(List<Long> entityIds)
-    {
-        IEntityPropertyTypeDAO entityPropertyTypeDAO = getEntityPropertyTypeDAO(entityKind);
-        entityPropertyTypeDAO.updateEntityModificationTimestamps(entityIds, getTransactionTimeStamp());
-    }
-
     private ScriptPE tryFindScript(NewETPTAssignment newAssignment)
     {
         if (newAssignment.getScriptName() == null)
@@ -211,7 +205,7 @@ public class EntityTypePropertyTypeBO extends AbstractBusinessObject implements
                                 registrator, validatedValue);
 
                 entityPropertyTypeDAO.createProperties(property, entityIds);
-                updateEntityModificationTimestamps(entityIds);
+                entityPropertyTypeDAO.updateEntityModificationTimestamps(entityIds);
             }
 
             if (operationLog.isDebugEnabled())
diff --git a/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/dataaccess/IEntityPropertyTypeDAO.java b/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/dataaccess/IEntityPropertyTypeDAO.java
index 409247eceff809aab969d5ba4f96afad22924062..22bc33d7a3ecfaa14dc896a1e20fa11a2b0ff535 100644
--- a/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/dataaccess/IEntityPropertyTypeDAO.java
+++ b/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/dataaccess/IEntityPropertyTypeDAO.java
@@ -16,7 +16,6 @@
 
 package ch.systemsx.cisd.openbis.generic.server.dataaccess;
 
-import java.util.Date;
 import java.util.List;
 
 import org.springframework.dao.DataAccessException;
@@ -127,5 +126,5 @@ public interface IEntityPropertyTypeDAO
      * the entity type and existing entities need to be updated with a default value for the mandatory property 2. If a property is unassigned from an
      * entity type.
      */
-    public void updateEntityModificationTimestamps(final List<Long> entityIds, final Date timestamp);
+    public void updateEntityModificationTimestamps(final List<Long> entityIds);
 }
diff --git a/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/dataaccess/db/EntityPropertyTypeDAO.java b/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/dataaccess/db/EntityPropertyTypeDAO.java
index 584e9e1908d316d08732c5822f144c08a440def2..0e57286be1d7f6ffebe968d65ec4a85bf3e35ae4 100644
--- a/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/dataaccess/db/EntityPropertyTypeDAO.java
+++ b/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/dataaccess/db/EntityPropertyTypeDAO.java
@@ -18,7 +18,6 @@ package ch.systemsx.cisd.openbis.generic.server.dataaccess.db;
 
 import java.io.Serializable;
 import java.util.ArrayList;
-import java.util.Date;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
@@ -247,8 +246,15 @@ final class EntityPropertyTypeDAO extends AbstractDAO implements IEntityProperty
     }
 
     @SuppressWarnings({ "unchecked", "rawtypes" })
-    public void updateEntityModificationTimestamps(final List<Long> entityIds, final Date timestamp)
+    public void updateEntityModificationTimestamps(final List<Long> entityIds)
     {
+        assert entityIds != null : "Null entityId list.";
+
+        if (entityIds.isEmpty())
+        {
+            return;
+        }
+
         getHibernateTemplate().execute(new HibernateCallback()
             {
                 @Override
@@ -276,7 +282,7 @@ final class EntityPropertyTypeDAO extends AbstractDAO implements IEntityProperty
                     SQLQuery clearQuery =
                             session.createSQLQuery(
                                     "update " + entityTableName + " set modification_timestamp = :timestamp where id in :entityIds ");
-                    clearQuery.setTimestamp("timestamp", timestamp);
+                    clearQuery.setTimestamp("timestamp", getTransactionTimeStamp());
                     clearQuery.setParameterList("entityIds", entityIds);
                     clearQuery.executeUpdate();
                     return null;
@@ -551,7 +557,7 @@ final class EntityPropertyTypeDAO extends AbstractDAO implements IEntityProperty
         template.clear();
         template.delete(assignment);
 
-        updateEntityModificationTimestamps(entityIds, getTransactionTimeStamp());
+        updateEntityModificationTimestamps(entityIds);
         scheduleDynamicPropertiesEvaluation(entityIds);
 
         if (operationLog.isInfoEnabled())
diff --git a/openbis/sourceTest/java/ch/systemsx/cisd/openbis/generic/server/business/bo/EntityTypePropertyTypeBOTest.java b/openbis/sourceTest/java/ch/systemsx/cisd/openbis/generic/server/business/bo/EntityTypePropertyTypeBOTest.java
index b78e25dc2293c36448c93ea9e03f52a0339810ca..1f240634f1ebcadea296cb8dd23ec60ccbb5e891 100644
--- a/openbis/sourceTest/java/ch/systemsx/cisd/openbis/generic/server/business/bo/EntityTypePropertyTypeBOTest.java
+++ b/openbis/sourceTest/java/ch/systemsx/cisd/openbis/generic/server/business/bo/EntityTypePropertyTypeBOTest.java
@@ -137,6 +137,7 @@ public final class EntityTypePropertyTypeBOTest extends AbstractBOTest
                             with(any(PersonPE.class)), with(validatedValue));
                     will(returnValue(property));
 
+                    allowing(entityPropertyTypeDAO).updateEntityModificationTimestamps(with(experimentIds));
                     one(entityPropertyTypeDAO).createProperties(property, experimentIds);
                 }
             });