diff --git a/datastore_server/dist/etc/service.properties b/datastore_server/dist/etc/service.properties
index 59c8200dc122583017e7cf53bf11d7e49b401fc4..05a40ddc3b80ba0770f2bff662b2b6ff7eaebbb2 100644
--- a/datastore_server/dist/etc/service.properties
+++ b/datastore_server/dist/etc/service.properties
@@ -144,3 +144,7 @@ main-thread.storage-processor = ch.systemsx.cisd.etlserver.DefaultStorageProcess
 # main-thread.storage-processor.sampleTypeCode = CELL_PLATE
 # main-thread.storage-processor.sampleTypeDescription = Screening Plate
 # main-thread.storage-processor.format = UNKNOWN V1.0
+
+# IStorageProcessor deleting files not matching specified regular expression
+# main-thread.storage-processor = ch.systemsx.cisd.etlserver.CifexStorageProcessor
+# main-thread.storage-processor.keep-file-regex = \\b(?!\\w*?request.properties)\\w+\\b