diff --git a/backend/tests/test_rebill_spot_check.py b/backend/tests/test_rebill_spot_check.py
index fe4c05d..52196e6 100644
--- a/backend/tests/test_rebill_spot_check.py
+++ b/backend/tests/test_rebill_spot_check.py
@@ -314,6 +314,28 @@ def test_full_pipeline_propagates_validate_error():
     assert "quota" in str(excinfo.value.body).lower()
 
 
+def test_claim_passes_shipped_sp40_local_validator():
+    """The shipped SP40 local validator (25 R-codes) passes the ClaimOutput.
+
+    The local validator at ``cyclone.parsers.validator.validate`` is the
+    structural pre-flight gate that mirrors what Edifabric checks at the
+    /v2/x12/validate level. Running the same claim through it confirms
+    the spot-check pipeline produces structurally-correct 837Ps even
+    when the live Edifabric API is unavailable.
+    """
+    from cyclone.parsers.payer import PayerConfig
+    from cyclone.parsers.validator import validate as validate_claim
+
+    visit = _visit()
+    claim = build_claim_output(visit)
+    report = validate_claim(claim, PayerConfig.co_medicaid())
+    assert report.passed, (
+        f"SP40 local validator rejected the claim: "
+        f"errors={[(i.rule, i.message) for i in report.errors]}"
+    )
+    assert not report.errors, f"unexpected errors: {report.errors}"
+
+
 # --- Helpers -----------------------------------------------------------