diff --git a/platform/core-impl/src/com/intellij/psi/search/ProjectScopeImpl.java b/platform/core-impl/src/com/intellij/psi/search/ProjectScopeImpl.java
index 684136c1b0e8..1b45424b150e 100644
--- a/platform/core-impl/src/com/intellij/psi/search/ProjectScopeImpl.java
+++ b/platform/core-impl/src/com/intellij/psi/search/ProjectScopeImpl.java
@@ -35,6 +35,8 @@ public class ProjectScopeImpl extends GlobalSearchScope {
   public boolean contains(VirtualFile file) {
     if (file instanceof VirtualFileWindow) return true;
 
+    if (myFileIndex.isInLibraryClasses(file) && !myFileIndex.isInSourceContent(file)) return false;
+
     return myFileIndex.isInContent(file);
   }