diff --git a/platform/lang-impl/src/com/intellij/codeInsight/completion/impl/CompletionServiceImpl.java b/platform/lang-impl/src/com/intellij/codeInsight/completion/impl/CompletionServiceImpl.java
index d84f431a65aa..dac6d6f15418 100644
--- a/platform/lang-impl/src/com/intellij/codeInsight/completion/impl/CompletionServiceImpl.java
+++ b/platform/lang-impl/src/com/intellij/codeInsight/completion/impl/CompletionServiceImpl.java
@@ -40,7 +40,7 @@ import java.util.ArrayList;
 /**
  * @author peter
  */
-public class CompletionServiceImpl extends CompletionService{
+public final class CompletionServiceImpl extends CompletionService{
   private static final Logger LOG = Logger.getInstance("#com.intellij.codeInsight.completion.impl.CompletionServiceImpl");
   private static volatile CompletionPhase ourPhase = CompletionPhase.NoCompletion;
   private static String ourPhaseTrace;