diff --git a/openbis/source/java/ch/systemsx/cisd/openbis/plugin/generic/client/web/client/IGenericClientServiceAsync.java b/openbis/source/java/ch/systemsx/cisd/openbis/plugin/generic/client/web/client/IGenericClientServiceAsync.java
index 3c604e80714b99309bfb2aea9067778869584b82..8b37e0012d75547262a0c63572d985000e8c29f4 100644
--- a/openbis/source/java/ch/systemsx/cisd/openbis/plugin/generic/client/web/client/IGenericClientServiceAsync.java
+++ b/openbis/source/java/ch/systemsx/cisd/openbis/plugin/generic/client/web/client/IGenericClientServiceAsync.java
@@ -71,7 +71,7 @@ public interface IGenericClientServiceAsync extends IClientServiceAsync
     /**
      * @see IGenericClientService#registerSamplesWithSilentOverrides(SampleType, String, String, String, boolean, String, String, boolean)
      */
-    public List<BatchRegistrationResult> registerSamplesWithSilentOverrides(final SampleType sampleType,
+    public void registerSamplesWithSilentOverrides(final SampleType sampleType,
             final String spaceIdentifierSilentOverrideOrNull,
             final String experimentIdentifierSilentOverrideOrNull,
             String sessionKey, boolean async, String userEmail, String defaultGroupIdentifier, boolean updateExisting,
@@ -89,7 +89,7 @@ public interface IGenericClientServiceAsync extends IClientServiceAsync
     /**
      * @see IGenericClientService#updateSamplesWithSilentOverrides(SampleType, String, String, String, boolean, String, String)
      */
-    public List<BatchRegistrationResult> updateSamplesWithSilentOverrides(final SampleType sampleType,
+    public void updateSamplesWithSilentOverrides(final SampleType sampleType,
             final String spaceIdentifierSilentOverrideOrNull,
             final String experimentIdentifierSilentOverrideOrNull,
             String sessionKey, boolean async, String userEmail, String defaultGroupIdentifier,