diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetPsiUtil.java b/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetPsiUtil.java
index 0484b6b4dc0..eae6507a6c2 100644
--- a/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetPsiUtil.java
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetPsiUtil.java
@@ -76,6 +76,7 @@ public class JetPsiUtil {
     }
 
     @Nullable
+    @Contract("!null -> !null")
     public static JetExpression deparenthesize(@Nullable JetExpression expression) {
         return deparenthesize(expression, /* deparenthesizeBinaryExpressionWithTypeRHS = */ true);
     }