diff --git a/hapi-fhir-validation/src/main/java/org/hl7/fhir/common/hapi/validation/support/CommonCodeSystemsTerminologyService.java b/hapi-fhir-validation/src/main/java/org/hl7/fhir/common/hapi/validation/support/CommonCodeSystemsTerminologyService.java
index cfea4d2ac89..41170364e85 100644
--- a/hapi-fhir-validation/src/main/java/org/hl7/fhir/common/hapi/validation/support/CommonCodeSystemsTerminologyService.java
+++ b/hapi-fhir-validation/src/main/java/org/hl7/fhir/common/hapi/validation/support/CommonCodeSystemsTerminologyService.java
@@ -335,14 +335,6 @@ public class CommonCodeSystemsTerminologyService implements IValidationSupport {
 	public static String getCodeSystemUrl(@Nonnull IBaseResource theCodeSystem) {
 		String url;
 		switch (theCodeSystem.getStructureFhirVersionEnum()) {
-			case DSTU2_HL7ORG: {
-				url = ((CodeSystem) theCodeSystem).getUrl();
-				break;
-			}
-			case DSTU3: {
-				url = ((org.hl7.fhir.dstu3.model.CodeSystem) theCodeSystem).getUrl();
-				break;
-			}
 			case R4: {
 				url = ((org.hl7.fhir.r4.model.CodeSystem) theCodeSystem).getUrl();
 				break;
@@ -351,8 +343,7 @@ public class CommonCodeSystemsTerminologyService implements IValidationSupport {
 				url = ((org.hl7.fhir.r5.model.CodeSystem) theCodeSystem).getUrl();
 				break;
 			}
-			case DSTU2:
-			case DSTU2_1:
+			case DSTU3:
 			default:
 				throw new IllegalArgumentException("Can not handle version: " + theCodeSystem.getStructureFhirVersionEnum());
 		}
diff --git a/hapi-fhir-validation/src/test/java/org/hl7/fhir/common/hapi/validation/support/CommonCodeSystemsTerminologyServiceTest.java b/hapi-fhir-validation/src/test/java/org/hl7/fhir/common/hapi/validation/support/CommonCodeSystemsTerminologyServiceTest.java
index 1be573dd025..b3cb3984ee9 100644
--- a/hapi-fhir-validation/src/test/java/org/hl7/fhir/common/hapi/validation/support/CommonCodeSystemsTerminologyServiceTest.java
+++ b/hapi-fhir-validation/src/test/java/org/hl7/fhir/common/hapi/validation/support/CommonCodeSystemsTerminologyServiceTest.java
@@ -5,6 +5,8 @@ import ca.uhn.fhir.context.FhirVersionEnum;
 import ca.uhn.fhir.context.support.ConceptValidationOptions;
 import ca.uhn.fhir.context.support.IValidationSupport;
 import ca.uhn.fhir.context.support.ValidationSupportContext;
+import ca.uhn.fhir.rest.server.exceptions.InvalidRequestException;
+
 import org.hl7.fhir.instance.model.api.IBaseResource;
 import org.hl7.fhir.r4.model.CodeSystem;
 import org.hl7.fhir.r4.model.ValueSet;
@@ -13,6 +15,9 @@ import org.junit.jupiter.api.Test;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.fail;
+
+import javax.annotation.Nonnull;
 
 public class CommonCodeSystemsTerminologyServiceTest {
 
@@ -114,4 +119,14 @@ public class CommonCodeSystemsTerminologyServiceTest {
 		assertEquals(null, cs);
 	}
 
+	@Test
+	public void testFetchCodeSystemUrlDstu3() {
+		try {
+			CommonCodeSystemsTerminologyService.getCodeSystemUrl(new org.hl7.fhir.dstu3.model.CodeSystem());
+
+			fail();
+		} catch (IllegalArgumentException e) {
+			assertEquals("Can not handle version: DSTU3", e.getMessage());
+		}
+	}
 }