diff --git a/org.hl7.fhir.validation/src/main/java/org/hl7/fhir/r5/validation/ValidationEngine.java b/org.hl7.fhir.validation/src/main/java/org/hl7/fhir/r5/validation/ValidationEngine.java
index c69a663c8..af2758d1c 100644
--- a/org.hl7.fhir.validation/src/main/java/org/hl7/fhir/r5/validation/ValidationEngine.java
+++ b/org.hl7.fhir.validation/src/main/java/org/hl7/fhir/r5/validation/ValidationEngine.java
@@ -1593,6 +1593,10 @@ public class ValidationEngine implements IValidatorResourceFetcher {
       return true; // we don't bother with those.
     if (context.fetchResource(Resource.class, url) != null)
       return true;
+    if (Utilities.existsInList(url, "http://hl7.org/fhir/sid/us-ssn", "http://hl7.org/fhir/sid/cvx", "http://hl7.org/fhir/sid/ndc", "http://hl7.org/fhir/sid/us-npi",
+       "http://hl7.org/fhir/sid/icd-10-vn", "http://hl7.org/fhir/sid/icd-10-cm", "http://hl7.org/fhir/sid/icd-9-cm", "http://hl7.org/fhir/w5", "http://hl7.org/fhir/fivews", "http://hl7.org/fhir/workflow")) {
+      return true;
+    }
     return false;
   }