diff --git a/rm-server/source/java/org/alfresco/module/org_alfresco_module_rm/classification/ContentClassificationServiceImpl.java b/rm-server/source/java/org/alfresco/module/org_alfresco_module_rm/classification/ContentClassificationServiceImpl.java
index 001ec25192..222eb8e500 100644
--- a/rm-server/source/java/org/alfresco/module/org_alfresco_module_rm/classification/ContentClassificationServiceImpl.java
+++ b/rm-server/source/java/org/alfresco/module/org_alfresco_module_rm/classification/ContentClassificationServiceImpl.java
@@ -28,6 +28,7 @@ import java.util.Map;
 import java.util.Set;
 
 import org.alfresco.model.ContentModel;
+import org.alfresco.model.QuickShareModel;
 import org.alfresco.module.org_alfresco_module_rm.classification.ClassificationServiceException.InvalidNode;
 import org.alfresco.module.org_alfresco_module_rm.classification.ClassificationServiceException.LevelIdNotFound;
 import org.alfresco.module.org_alfresco_module_rm.classification.model.ClassifiedContentModel;
@@ -98,6 +99,10 @@ public class ContentClassificationServiceImpl extends ServiceBaseImpl implements
             throw new UnsupportedOperationException(
                         "The content has already been classified. Reclassification is currently not supported.");
         }
+        if (nodeService.hasAspect(content, QuickShareModel.ASPECT_QSHARE))
+        {
+            throw new IllegalStateException("A shared content cannot be classified.");
+        }
         if (!securityClearanceService.isCurrentUserClearedForClassification(classificationLevelId))
         {
             throw new LevelIdNotFound(classificationLevelId);
diff --git a/rm-server/unit-test/java/org/alfresco/module/org_alfresco_module_rm/classification/ContentClassificationServiceImplUnitTest.java b/rm-server/unit-test/java/org/alfresco/module/org_alfresco_module_rm/classification/ContentClassificationServiceImplUnitTest.java
index 4823ebfe4c..6aa36b1c2c 100644
--- a/rm-server/unit-test/java/org/alfresco/module/org_alfresco_module_rm/classification/ContentClassificationServiceImplUnitTest.java
+++ b/rm-server/unit-test/java/org/alfresco/module/org_alfresco_module_rm/classification/ContentClassificationServiceImplUnitTest.java
@@ -18,6 +18,7 @@
  */
 package org.alfresco.module.org_alfresco_module_rm.classification;
 
+import static com.google.common.collect.Sets.newHashSet;
 import static org.alfresco.module.org_alfresco_module_rm.test.util.AlfMock.generateNodeRef;
 import static org.alfresco.module.org_alfresco_module_rm.test.util.AlfMock.generateText;
 import static org.junit.Assert.assertEquals;
@@ -38,7 +39,9 @@ import java.util.Set;
 
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Sets;
+
 import org.alfresco.model.ContentModel;
+import org.alfresco.model.QuickShareModel;
 import org.alfresco.module.org_alfresco_module_rm.classification.ClassificationServiceException.InvalidNode;
 import org.alfresco.module.org_alfresco_module_rm.classification.ClassificationServiceException.LevelIdNotFound;
 import org.alfresco.module.org_alfresco_module_rm.classification.model.ClassifiedContentModel;
@@ -142,6 +145,18 @@ public class ContentClassificationServiceImplUnitTest implements ClassifiedConte
                     Sets.newHashSet("reasonId1", "reasonId2"), classifiedContent);
     }
 
+    /** Classify a piece of content that has already been shared */
+    @Test(expected = IllegalStateException.class)
+    public void classifySharedContent()
+    {
+        NodeRef sharedContent = generateNodeRef(mockNodeService);
+        when(mockDictionaryService.isSubClass(mockNodeService.getType(sharedContent), ContentModel.TYPE_CONTENT)).thenReturn(true);
+        when(mockNodeService.hasAspect(sharedContent, QuickShareModel.ASPECT_QSHARE)).thenReturn(true);
+
+        // Call the method under test.
+        contentClassificationServiceImpl.classifyContent(generateText(), generateText(), newHashSet(generateText(), generateText()), sharedContent);
+    }
+
     /**
      * Check that a user can't classify content with a level that either (a) doesn't exist, or (b) they don't have
      * clearance for.  (Both cases are covered by the same flow through the code).