diff --git a/plugins/groovy/src/org/jetbrains/plugins/groovy/codeInspection/unusedDef/UnusedDefInspection.java b/plugins/groovy/src/org/jetbrains/plugins/groovy/codeInspection/unusedDef/UnusedDefInspection.java
index c6cec4247bfe..fb8e2f0e6c12 100644
--- a/plugins/groovy/src/org/jetbrains/plugins/groovy/codeInspection/unusedDef/UnusedDefInspection.java
+++ b/plugins/groovy/src/org/jetbrains/plugins/groovy/codeInspection/unusedDef/UnusedDefInspection.java
@@ -33,6 +33,7 @@ import gnu.trove.TObjectProcedure;
 import org.jetbrains.annotations.Nls;
 import org.jetbrains.annotations.NonNls;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 import org.jetbrains.plugins.groovy.codeInspection.GroovyInspectionBundle;
 import org.jetbrains.plugins.groovy.codeInspection.GroovyLocalInspectionBase;
 import org.jetbrains.plugins.groovy.lang.psi.GrControlFlowOwner;
@@ -146,7 +147,7 @@ public class UnusedDefInspection extends GroovyLocalInspectionBase {
     });
   }
 
-  private boolean isUsedInToplevelFlowOnly(PsiElement element) {
+  private static boolean isUsedInToplevelFlowOnly(PsiElement element) {
     GrVariable var = null;
     if (element instanceof GrVariable) {
       var = (GrVariable) element;
@@ -159,7 +160,7 @@ public class UnusedDefInspection extends GroovyLocalInspectionBase {
       final GroovyPsiElement scope = getScope(var);
       if (scope == null) {
         PsiFile file = var.getContainingFile();
-        LOG.error(file == null ? "no file???" : DebugUtil.psiToString(file, true, false));
+        LOG.error(file == null ? "no file??? var of type"+ var.getClass().getCanonicalName() : DebugUtil.psiToString(file, true, false));
       }
 
       return ReferencesSearch.search(var, new LocalSearchScope(scope)).forEach(new Processor<PsiReference>() {
@@ -172,11 +173,12 @@ public class UnusedDefInspection extends GroovyLocalInspectionBase {
     return true;
   }
 
-  private GroovyPsiElement getScope(PsiElement var) {
-    return PsiTreeUtil.getParentOfType(var, GrClosableBlock.class, GrMethod.class, GrClassInitializer.class, GroovyFileBase.class);
+  @Nullable
+  private static GroovyPsiElement getScope(PsiElement var) {
+    return PsiTreeUtil.getContextOfType(var, GrClosableBlock.class, GrMethod.class, GrClassInitializer.class, GroovyFileBase.class);
   }
 
-  private boolean isLocalAssignment(PsiElement element) {
+  private static boolean isLocalAssignment(PsiElement element) {
     if (element instanceof GrVariable) {
       return isLocalVariable((GrVariable) element, false);
     } else if (element instanceof GrReferenceExpression) {
@@ -187,11 +189,8 @@ public class UnusedDefInspection extends GroovyLocalInspectionBase {
     return false;
   }
 
-  private boolean isLocalVariable(GrVariable var, boolean parametersAllowed) {
-    if (var instanceof GrField) return false;
-    else if (var instanceof GrParameter && !parametersAllowed) return false;
-
-    return true;
+  private static boolean isLocalVariable(GrVariable var, boolean parametersAllowed) {
+    return !(var instanceof GrField || var instanceof GrParameter && !parametersAllowed);
   }
 
   public boolean isEnabledByDefault() {
diff --git a/plugins/groovy/src/org/jetbrains/plugins/groovy/lang/psi/impl/synthetic/ClosureSyntheticParameter.java b/plugins/groovy/src/org/jetbrains/plugins/groovy/lang/psi/impl/synthetic/ClosureSyntheticParameter.java
index 092ce0ec2eee..de967e9c9f7e 100644
--- a/plugins/groovy/src/org/jetbrains/plugins/groovy/lang/psi/impl/synthetic/ClosureSyntheticParameter.java
+++ b/plugins/groovy/src/org/jetbrains/plugins/groovy/lang/psi/impl/synthetic/ClosureSyntheticParameter.java
@@ -79,11 +79,6 @@ public class ClosureSyntheticParameter extends GrLightParameter implements Navig
     return myClosure;
   }
 
-  @Override
-  public PsiElement getContext() {
-    return myClosure;
-  }
-
   @Override
   public GrExpression getDefaultInitializer() {
     return GroovyPsiElementFactory.getInstance(getProject()).createExpressionFromText("null");
diff --git a/plugins/groovy/src/org/jetbrains/plugins/groovy/lang/psi/impl/synthetic/GrLightParameter.java b/plugins/groovy/src/org/jetbrains/plugins/groovy/lang/psi/impl/synthetic/GrLightParameter.java
index ea8b68dd1ec4..e9001f166b08 100644
--- a/plugins/groovy/src/org/jetbrains/plugins/groovy/lang/psi/impl/synthetic/GrLightParameter.java
+++ b/plugins/groovy/src/org/jetbrains/plugins/groovy/lang/psi/impl/synthetic/GrLightParameter.java
@@ -16,6 +16,7 @@
 package org.jetbrains.plugins.groovy.lang.psi.impl.synthetic;
 
 import com.intellij.psi.PsiElement;
+import com.intellij.psi.PsiFile;
 import com.intellij.psi.PsiType;
 import com.intellij.psi.impl.light.LightParameter;
 import com.intellij.util.IncorrectOperationException;
@@ -34,7 +35,7 @@ public class GrLightParameter extends LightParameter implements GrParameter {
   public static final GrLightParameter[] EMPTY_ARRAY = new GrLightParameter[0];
   private volatile boolean myOptional;
 
-  public GrLightParameter(@NotNull String name, @NotNull PsiType type, PsiElement scope) {
+  public GrLightParameter(@NotNull String name, @NotNull PsiType type, @NotNull PsiElement scope) {
     super(name, type, scope, GroovyFileType.GROOVY_LANGUAGE);
   }
 
@@ -46,6 +47,16 @@ public class GrLightParameter extends LightParameter implements GrParameter {
     return null;
   }
 
+  @Override
+  public PsiElement getContext() {
+    return getDeclarationScope();
+  }
+
+  @Override
+  public PsiFile getContainingFile() {
+    return getDeclarationScope().getContainingFile();
+  }
+
   public GrLightParameter setOptional(boolean optional) {
     myOptional = optional;
     return this;
diff --git a/plugins/groovy/test/org/jetbrains/plugins/groovy/lang/GroovyHighlightingTest.java b/plugins/groovy/test/org/jetbrains/plugins/groovy/lang/GroovyHighlightingTest.java
index 0bbd077d5d68..5f0dd84f232a 100644
--- a/plugins/groovy/test/org/jetbrains/plugins/groovy/lang/GroovyHighlightingTest.java
+++ b/plugins/groovy/test/org/jetbrains/plugins/groovy/lang/GroovyHighlightingTest.java
@@ -370,4 +370,9 @@ public class GroovyHighlightingTest extends LightCodeInsightFixtureTestCase {
   public void testConstructorWithAllParametersOptional() {
     doTest();
   }
+
+  public void testUnusedDefsForArgs() {
+    doTest(new UnusedDefInspection());
+  }
+
 }
\ No newline at end of file
diff --git a/plugins/groovy/testdata/highlighting/UnusedDefsForArgs.groovy b/plugins/groovy/testdata/highlighting/UnusedDefsForArgs.groovy
new file mode 100644
index 000000000000..6c4a1ae35984
--- /dev/null
+++ b/plugins/groovy/testdata/highlighting/UnusedDefsForArgs.groovy
@@ -0,0 +1 @@
+<warning descr="Assignment is not used">args</warning> = []
\ No newline at end of file