diff --git a/crates/fidc-core/src/manual_corporate_replay.rs b/crates/fidc-core/src/manual_corporate_replay.rs
index 42027a1..3f35049 100644
--- a/crates/fidc-core/src/manual_corporate_replay.rs
+++ b/crates/fidc-core/src/manual_corporate_replay.rs
@@ -174,12 +174,16 @@ impl ManualCorporateReplay {
         let expected = current.financial_replay_identity();
         let reference_identity = reference.financial_replay_identity();
         if reference_identity != expected {
+            let differing = expected.as_object().into_iter().flat_map(|value| value.keys())
+                .chain(reference_identity.as_object().into_iter().flat_map(|value| value.keys()))
+                .collect::<BTreeSet<_>>().into_iter().filter(|key| expected.get(*key)!=reference_identity.get(*key))
+                .cloned().collect::<Vec<_>>().join(",");
             return Err(format!(
-                "manual corporate ledger coverage mismatch: symbol={} observed_at={} expected={} replayed={}",
+                "manual corporate ledger coverage mismatch: symbol={} observed_at={} expected={} replayed={} differing_fields={}",
                 observation.order.symbol,
                 observation.fill.observed_at,
                 digest(&expected)?,
-                digest(&reference_identity)?
+                digest(&reference_identity)?, differing
             ));
         }
         let replayed = self.replay(