diff --git a/src/applications/project/engine/PhabricatorBoardLayoutEngine.php b/src/applications/project/engine/PhabricatorBoardLayoutEngine.php
--- a/src/applications/project/engine/PhabricatorBoardLayoutEngine.php
+++ b/src/applications/project/engine/PhabricatorBoardLayoutEngine.php
@@ -4,7 +4,7 @@
 
   private $viewer;
   private $boardPHIDs;
-  private $objectPHIDs;
+  private $objectPHIDs = array();
   private $boards;
   private $columnMap = array();
   private $objectColumnMap = array();