diff --git a/src/main/java/org/purl/sword/server/fedora/fedoraObjects/FedoraRepository.java b/src/main/java/org/purl/sword/server/fedora/fedoraObjects/FedoraRepository.java
index 12a6164..f3006ce 100644
--- a/src/main/java/org/purl/sword/server/fedora/fedoraObjects/FedoraRepository.java
+++ b/src/main/java/org/purl/sword/server/fedora/fedoraObjects/FedoraRepository.java
@@ -193,16 +193,13 @@ public void modifyDatastream(String pid, Datastream update, String logMessage) t
                     original.getFormatURI(),
                     content,
                     original.getChecksumType(),
-                    original.getChecksum(),
+                    null,
                     logMessage,
                     false);
         } else {
             final String contentLocationUrl =
                     (update instanceof URLContentLocationDatastream) ?
                             ((URLContentLocationDatastream) update).getURL() : null;
-            final String checksum =
-                    (contentLocationUrl != null) ?
-                            original.getChecksum() : null;
 
             _APIM.modifyDatastreamByReference(
                     pid,
@@ -213,7 +210,7 @@ public void modifyDatastream(String pid, Datastream update, String logMessage) t
                     original.getFormatURI(),
                     contentLocationUrl,
                     original.getChecksumType(),
-                    checksum,
+                    null,
                     logMessage,
                     false);
         }