diff --git a/litellm/proxy/guardrails/guardrail_hooks/litellm_content_filter/patterns.json b/litellm/proxy/guardrails/guardrail_hooks/litellm_content_filter/patterns.json
index 1accf8ac0c9..97e4646898f 100644
--- a/litellm/proxy/guardrails/guardrail_hooks/litellm_content_filter/patterns.json
+++ b/litellm/proxy/guardrails/guardrail_hooks/litellm_content_filter/patterns.json
@@ -408,7 +408,7 @@
     {
       "name": "eu_iban_enhanced",
       "display_name": "IBAN (Enhanced EU Format)",
-      "pattern": "\\b[A-Z]{2}[0-9]{2}[A-Z0-9]{4}[0-9]{7}([A-Z0-9]?){0,16}\\b",
+      "pattern": "\\b[A-Z]{2}[0-9]{2}[A-Z0-9]{4}[0-9]{7}[A-Z0-9]{0,16}\\b",
       "category": "EU PII Patterns",
       "description": "Enhanced IBAN detection with more specific format validation (2 letter country + 2 check digits + 4 char bank code + 7 digit account base + optional 0-16 alphanumeric)"
     },