diff --git oak-upgrade/src/main/java/org/apache/jackrabbit/oak/upgrade/JackrabbitNodeState.java oak-upgrade/src/main/java/org/apache/jackrabbit/oak/upgrade/JackrabbitNodeState.java
index f1dbb89..b4a513b 100644
--- oak-upgrade/src/main/java/org/apache/jackrabbit/oak/upgrade/JackrabbitNodeState.java
+++ oak-upgrade/src/main/java/org/apache/jackrabbit/oak/upgrade/JackrabbitNodeState.java
@@ -599,24 +599,26 @@ class JackrabbitNodeState extends AbstractNodeState {
                 try {
                     return value.getLength();
                 } catch (RepositoryException e) {
                     warn("Unable to access blob length", e);
                     return 0;
                 }
             }
+
             @Nonnull
             @Override
             public InputStream getNewStream() {
                 try {
                     return value.getStream();
                 } catch (RepositoryException e) {
                     warn("Unable to access blob contents", e);
                     return new ByteArrayInputStream(new byte[0]);
                 }
             }
+
             @Override
             public String getReference() {
                 if (!useBinaryReferences) {
                     return null;
                 }
                 try {
                     Binary binary = value.getBinary();
@@ -630,14 +632,30 @@ class JackrabbitNodeState extends AbstractNodeState {
                         binary.dispose();
                     }
                 } catch (RepositoryException e) {
                     warn("Unable to get blob reference", e);
                     return null;
                 }
             }
+
+            @Override
+            public String getContentIdentity() {
+                final String reference = getReference();
+                if (reference != null) {
+                    final int pos = reference.indexOf(":");
+                    final String blobHash;
+                    if (pos > -1) {
+                        blobHash = reference.substring(0, pos);
+                    } else {
+                        blobHash = reference;
+                    }
+                    return blobHash + "#" + length();
+                }
+                return super.getContentIdentity();
+            }
         };
     }
 
     private String createName(Name name) {
         String uri = name.getNamespaceURI();
         String local = name.getLocalName();
         if (uri == null || uri.isEmpty()) {