diff --git a/scripts/audit/anomalies.py b/scripts/audit/anomalies.py
index 7b1ac62e2..c856a5d17 100644
--- a/scripts/audit/anomalies.py
+++ b/scripts/audit/anomalies.py
@@ -175,9 +175,14 @@ def _zero_works_post_differs(a: PropertyAudit) -> Optional[str]:
 def _effective_lodged_divergence(a: PropertyAudit) -> Optional[str]:
     """The Effective baseline is far from the lodged accredited figure (≥15 SAP).
     Often legitimate (overrides / pre-SAP10 rebaseline), but worth a look — a big
-    gap can also mean a bad override or a calculator divergence."""
+    gap can also mean a bad override or a calculator divergence.
+
+    Lodged scores below 13 are handed off to ``implausible-lodged-score`` — they
+    indicate corrupt upstream EPC register data, not a modelling divergence."""
     if a.effective_sap is None or a.lodged_sap is None:
         return None
+    if a.lodged_sap < 13:
+        return None
     gap = a.effective_sap - a.lodged_sap
     if abs(gap) < 15:
         return None