diff --git a/src/main/java/com/epimorphics/registry/commands/CommandRead.java b/src/main/java/com/epimorphics/registry/commands/CommandRead.java
index 547d1366..c3f2977c 100644
--- a/src/main/java/com/epimorphics/registry/commands/CommandRead.java
+++ b/src/main/java/com/epimorphics/registry/commands/CommandRead.java
@@ -203,6 +203,20 @@ public Response doExecute() {
             } else if (ri.getEntity() != null) {
                 m.add( ri.getEntity().getModel() );
             }
+
+            // Full solution here would also apply this to the case where entityWithMetadata is set
+            // that's why the check is inject at this point.
+            // That full solution currently disabled due to test case issues.
+//            if (graphEntity || entityWithMetadata) {
+            if (graphEntity ) {
+                // Validate that the graph contains a matching entity definition with a type property.
+                // For both plain and graph registered entities this is enforced at registration time.
+                // If this is an external entity then the graph will not contain a matching root resource
+                // and we prefer to return a 404 in that case.
+                if ( ! m.getResource(target).hasProperty(RDF.type) ) {
+                    throw new NotFoundException();
+                }
+            }
         }
         
         List<Resource> members = (paged) ? new ArrayList<Resource>(length) : new ArrayList<Resource>() ;
diff --git a/src/test/java/com/epimorphics/registry/webapi/TestAPI.java b/src/test/java/com/epimorphics/registry/webapi/TestAPI.java
index fa162a21..65acc1b5 100644
--- a/src/test/java/com/epimorphics/registry/webapi/TestAPI.java
+++ b/src/test/java/com/epimorphics/registry/webapi/TestAPI.java
@@ -39,9 +39,6 @@
 import javax.ws.rs.core.Response;
 
 import org.apache.jena.riot.RDFDataMgr;
-import org.apache.shiro.SecurityUtils;
-import org.apache.shiro.mgt.DefaultSecurityManager;
-import org.junit.Before;
 import org.junit.Test;
 
 import com.epimorphics.rdfutil.QueryUtil;
@@ -104,6 +101,8 @@ public void testAll() throws IOException {
         // Puts red in reg1/red
         doItemRegistrationTests();
 
+        // Reference red from another register
+        testCrossRegisterReference();
         
         // Adds external resource reg1/black
         doExternalRegistrationTests();
@@ -265,6 +264,19 @@ private void doRegisterRegistrationTests() {
         assertEquals("Register the same again", 403, postFileStatus("test/reg1.ttl", BASE_URL));
     }
 
+    private void testCrossRegisterReference() {
+        Response response = postFile("test/reg4.ttl", BASE_URL, "text/turtle");
+        assertEquals("Register a register", 201, response.getStatus());
+        assertEquals(201, postFileStatus("test/reference.ttl", BASE_URL + "reg4"));
+
+        assertEquals(404, getResponse(BASE_URL + "reg4/reference").getStatus());
+
+        Model m = getModelResponse(BASE_URL + "reg4/_reference");
+        checkModelResponse(m, ROOT_REGISTER + "reg1/red", "test/expected/reference_red.ttl");
+
+        assertEquals(303, post(BASE_URL + "reg4?real_delete").getStatus());
+    }
+
     // Assumes reg1 has been created
     // Adds an item (reg1/red) and checks it all looks OK
     // Leaves reg1/red in plce
diff --git a/test/expected/reference_red.ttl b/test/expected/reference_red.ttl
new file mode 100644
index 00000000..38e8bc07
--- /dev/null
+++ b/test/expected/reference_red.ttl
@@ -0,0 +1,19 @@
+@prefix rdf:  <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
+@prefix owl:  <http://www.w3.org/2002/07/owl#> .
+@prefix xsd:  <http://www.w3.org/2001/XMLSchema#> .
+@prefix dct:  <http://purl.org/dc/terms/> .
+@prefix skos: <http://www.w3.org/2004/02/skos/core#> .
+
+@prefix reg:  <http://purl.org/linked-data/registry#> .
+
+<_reference> a reg:RegisterItem;
+    reg:definition [
+       reg:entity  <http://location.data.gov.uk/reg1/red>;
+    ]
+.
+
+<http://location.data.gov.uk/reg1/red> a skos:Concept;
+    rdfs:label "red"
+    .
+
diff --git a/test/reference.ttl b/test/reference.ttl
new file mode 100644
index 00000000..71515c86
--- /dev/null
+++ b/test/reference.ttl
@@ -0,0 +1,19 @@
+@prefix rdf:  <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
+@prefix owl:  <http://www.w3.org/2002/07/owl#> .
+@prefix xsd:  <http://www.w3.org/2001/XMLSchema#> .
+@prefix dct:  <http://purl.org/dc/terms/> .
+@prefix skos: <http://www.w3.org/2004/02/skos/core#> .
+
+@prefix reg:  <http://purl.org/linked-data/registry#> .
+
+<_reference> a reg:RegisterItem;
+    reg:definition [
+       reg:entity  <http://location.data.gov.uk/reg1/red>;
+    ] 
+.
+
+<http://location.data.gov.uk/reg1/red> a skos:Concept;
+    rdfs:label "red"
+.
+
diff --git a/test/reg4.ttl b/test/reg4.ttl
new file mode 100644
index 00000000..25d67ff2
--- /dev/null
+++ b/test/reg4.ttl
@@ -0,0 +1,25 @@
+@prefix rdf:  <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
+@prefix owl:  <http://www.w3.org/2002/07/owl#> .
+@prefix xsd:  <http://www.w3.org/2001/XMLSchema#> .
+@prefix dct:  <http://purl.org/dc/terms/> .
+@prefix dc:   <http://purl.org/dc/elements/1.1/> .
+@prefix foaf: <http://xmlns.com/foaf/0.1/> .
+@prefix skos: <http://www.w3.org/2004/02/skos/core#> .
+@prefix version:  <http://purl.org/linked-data/version#> .
+@prefix ldp:  <http://www.w3.org/ns/ldp#> .
+@prefix ssd:  <http://www.w3.org/ns/sparql-service-description#> .
+@prefix vs:   <http://www.w3.org/2003/06/sw-vocab-status/ns#> .
+@prefix void: <http://rdfs.org/ns/void#> .
+@prefix prov: <http://www.w3.org/ns/prov#> .
+
+@prefix reg:  <http://purl.org/linked-data/registry#> .
+
+<reg4> a reg:Register, skos:Collection ;
+    ldp:membershipPredicate skos:member;
+    rdfs:label "register 4"@en;
+    dct:description "Example register 4"@en;
+    reg:owner      <http://example.com/department> ;
+    reg:manager   <http://example.com/registryManagementLtd>
+.
+