diff --git a/Timeline/TimelineActivityProvider.php b/Timeline/TimelineActivityProvider.php
index b54fe34b0..a19a659e1 100644
--- a/Timeline/TimelineActivityProvider.php
+++ b/Timeline/TimelineActivityProvider.php
@@ -101,6 +101,10 @@ class TimelineActivityProvider implements TimelineProviderInterface
                 $role);
         $associationMapping = $metadataActivity->getAssociationMapping('person');
         
+        if (count($reachableCenters) === 0) {
+            return 'FALSE = TRUE';
+        }
+        
         // we start with activities having the person_id linked to person 
         // (currently only context "person" is supported)
         $whereClause = sprintf('%s = %d',