diff --git a/tests/PhpSpreadsheetTests/MergedCells.php b/tests/PhpSpreadsheetTests/MergedCells.php
index 753c0077..bf0772d2 100644
--- a/tests/PhpSpreadsheetTests/MergedCells.php
+++ b/tests/PhpSpreadsheetTests/MergedCells.php
@@ -11,9 +11,9 @@ class MergedCells extends TestCase
     public function providerMergedCells()
     {
         return [
-//            ['Html'],
-//            ['Xls'],
-//            ['Xlsx'],
+            ['Html'],
+            ['Xls'],
+            ['Xlsx'],
             ['Ods'],
         ];
     }