diff --git a/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/annotator/GroovyAnnotator.java b/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/annotator/GroovyAnnotator.java
index 36ea0524671f..e539b02ea6a2 100644
--- a/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/annotator/GroovyAnnotator.java
+++ b/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/annotator/GroovyAnnotator.java
@@ -38,7 +38,6 @@ import com.intellij.openapi.util.TextRange;
 import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.psi.*;
 import com.intellij.psi.impl.ExpressionConverter;
-import com.intellij.psi.impl.light.LightElement;
 import com.intellij.psi.search.GlobalSearchScope;
 import com.intellij.psi.search.searches.SuperMethodsSearch;
 import com.intellij.psi.tree.IElementType;
@@ -97,12 +96,9 @@ import org.jetbrains.plugins.groovy.lang.psi.api.util.GrStatementOwner;
 import org.jetbrains.plugins.groovy.lang.psi.dataFlow.types.TypeInferenceHelper;
 import org.jetbrains.plugins.groovy.lang.psi.impl.PsiImplUtil;
 import org.jetbrains.plugins.groovy.lang.psi.impl.auxiliary.modifiers.GrAnnotationCollector;
-import org.jetbrains.plugins.groovy.lang.psi.impl.signatures.GrClosureSignatureUtil;
 import org.jetbrains.plugins.groovy.lang.psi.impl.statements.expressions.TypesUtil;
 import org.jetbrains.plugins.groovy.lang.psi.impl.synthetic.GroovyScriptClass;
-import org.jetbrains.plugins.groovy.lang.psi.util.GrStringUtil;
-import org.jetbrains.plugins.groovy.lang.psi.util.GrTraitUtil;
-import org.jetbrains.plugins.groovy.lang.psi.util.GroovyPropertyUtils;
+import org.jetbrains.plugins.groovy.lang.psi.util.*;
 import org.jetbrains.plugins.groovy.lang.psi.util.PsiUtil;
 import org.jetbrains.plugins.groovy.lang.resolve.ResolveUtil;
 import org.jetbrains.plugins.groovy.lang.resolve.ast.GrInheritConstructorContributor;
@@ -430,7 +426,6 @@ public class GroovyAnnotator extends GroovyElementVisitor {
     }
     checkTypeDefinition(myHolder, typeDefinition);
 
-    checkDuplicateMethod(typeDefinition, myHolder);
     checkImplementedMethodsOfClass(myHolder, typeDefinition);
     checkConstructors(myHolder, typeDefinition);
 
@@ -610,6 +605,7 @@ public class GroovyAnnotator extends GroovyElementVisitor {
 
   @Override
   public void visitMethod(GrMethod method) {
+    checkDuplicateMethod(method);
     checkMethodWithTypeParamsShouldHaveReturnType(myHolder, method);
     checkInnerMethod(myHolder, method);
     checkOptionalParametersInAbstractMethod(myHolder, method);
@@ -1484,7 +1480,6 @@ public class GroovyAnnotator extends GroovyElementVisitor {
   public void visitFile(GroovyFileBase file) {
     final PsiClass scriptClass = file.getScriptClass();
     if (scriptClass != null) {
-      checkDuplicateMethod(scriptClass, myHolder);
       checkSameNameMethodsWithDifferentAccessModifiers(myHolder, file.getCodeMethods());
     }
   }
@@ -1992,31 +1987,31 @@ public class GroovyAnnotator extends GroovyElementVisitor {
     }
   }
 
-  private static void checkDuplicateMethod(PsiClass clazz, AnnotationHolder holder) {
-    MultiMap<MethodSignature, PsiMethod> map = GrClosureSignatureUtil.findRawMethodSignatures(clazz.getMethods(), clazz);
-    processMethodDuplicates(map, holder);
-  }
-
-  protected static void processMethodDuplicates(MultiMap<MethodSignature, PsiMethod> map, AnnotationHolder holder) {
-    for (MethodSignature signature : map.keySet()) {
-      Collection<PsiMethod> methods = map.get(signature);
-      if (methods.size() > 1) {
-        for (Iterator<PsiMethod> iterator = methods.iterator(); iterator.hasNext(); ) {
-          PsiMethod method = iterator.next();
-          if (method instanceof LightElement) iterator.remove();
-        }
-
-        if (methods.size() < 2) continue;
-        String signaturePresentation = GroovyPresentationUtil.getSignaturePresentation(signature);
-        for (PsiMethod method : methods) {
-          //noinspection ConstantConditions
-          holder.createErrorAnnotation(GrHighlightUtil.getMethodHeaderTextRange(method), GroovyBundle
-            .message("method.duplicate", signaturePresentation, method.getContainingClass().getName()));
-        }
+  private void checkDuplicateMethod(@NotNull GrMethod method) {
+    PsiClass clazz = method.getContainingClass();
+    if (clazz == null) return;
+    GrReflectedMethod[] reflectedMethods = method.getReflectedMethods();
+    if (reflectedMethods.length == 0) {
+      doCheckDuplicateMethod(method, clazz);
+    }
+    else {
+      for (GrReflectedMethod reflectedMethod : reflectedMethods) {
+        doCheckDuplicateMethod(reflectedMethod, clazz);
       }
     }
   }
 
+  private void doCheckDuplicateMethod(@NotNull GrMethod method, @NotNull PsiClass clazz) {
+    MethodSignature signature = GrClassImplUtil.getDuplicatedMethods(clazz).get(method);
+    if (signature == null) return;
+    String signaturePresentation = GroovyPresentationUtil.getSignaturePresentation(signature);
+    GrMethod original = method instanceof GrReflectedMethod ? ((GrReflectedMethod)method).getBaseMethod() : method;
+    myHolder.createErrorAnnotation(
+      GrHighlightUtil.getMethodHeaderTextRange(original),
+      GroovyBundle.message("method.duplicate", signaturePresentation, clazz.getName())
+    );
+  }
+
   private static void checkTypeDefinition(AnnotationHolder holder, GrTypeDefinition typeDefinition) {
     final GroovyConfigUtils configUtils = GroovyConfigUtils.getInstance();
     if (typeDefinition.isAnonymous()) {
diff --git a/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/util/GrClassImplUtil.java b/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/util/GrClassImplUtil.java
index e347ce2fb1f4..cb20e0bf2a87 100644
--- a/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/util/GrClassImplUtil.java
+++ b/plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/util/GrClassImplUtil.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2000-2015 JetBrains s.r.o.
+ * Copyright 2000-2016 JetBrains s.r.o.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -33,6 +33,7 @@ import com.intellij.psi.util.PsiUtil;
 import com.intellij.util.ArrayUtil;
 import com.intellij.util.Function;
 import com.intellij.util.containers.ContainerUtil;
+import com.intellij.util.containers.MostlySingularMultiMap;
 import com.intellij.util.containers.hash.HashSet;
 import gnu.trove.TObjectIntHashMap;
 import org.jetbrains.annotations.NonNls;
@@ -636,4 +637,29 @@ public class GrClassImplUtil {
       }
     });
   }
+
+  @NotNull
+  public static Map<PsiMethod, MethodSignature> getDuplicatedMethods(@NotNull PsiClass clazz) {
+    return CachedValuesManager.getCachedValue(clazz, () -> {
+      PsiElementFactory factory = JavaPsiFacade.getInstance(clazz.getProject()).getElementFactory();
+
+      MostlySingularMultiMap<MethodSignature, PsiMethod> signatures = MostlySingularMultiMap.newMap();
+      for (PsiMethod method : clazz.getMethods()) {
+        MethodSignature signature = method.getSignature(factory.createRawSubstitutor(method));
+        signatures.add(signature, method);
+      }
+
+      Map<PsiMethod, MethodSignature> result = ContainerUtil.newHashMap();
+      for (MethodSignature signature : signatures.keySet()) {
+        if (signatures.valuesForKey(signature) > 1) {
+          signatures.processForKey(signature, m -> {
+            result.put(m, signature);
+            return true;
+          });
+        }
+      }
+
+      return CachedValueProvider.Result.create(result, clazz);
+    });
+  }
 }