diff --git a/calendar/inc/class.calendar_boupdate.inc.php b/calendar/inc/class.calendar_boupdate.inc.php
index 90b5ca6d86..1231eb1958 100644
--- a/calendar/inc/class.calendar_boupdate.inc.php
+++ b/calendar/inc/class.calendar_boupdate.inc.php
@@ -1098,8 +1098,8 @@ class calendar_boupdate extends calendar_bo
 						'email' => is_numeric($userid) ? Api\Accounts::id2name($userid, 'account_email') : $userid,
 						'avatar' => (string)$avatar,
 						'account_id' => $userid,
-						'cal_id' => $details['id']
-					], [], $startdate, $enddate);
+							'cal_id' => $details['id']
+					], ['participants' =>array_filter($event['participants'], function($key){return is_numeric($key);}, ARRAY_FILTER_USE_KEY)], $startdate, $enddate);
 					$event_arr['videoconference'] = [
 						'field' => lang('Video Conference'),
 						'data'  => $details['videoconference'],
diff --git a/calendar/inc/class.calendar_groupdav.inc.php b/calendar/inc/class.calendar_groupdav.inc.php
index 804c6383e2..f415e68bcc 100644
--- a/calendar/inc/class.calendar_groupdav.inc.php
+++ b/calendar/inc/class.calendar_groupdav.inc.php
@@ -692,7 +692,7 @@ class calendar_groupdav extends Api\CalDAV\Handler
 					'avatar' => (string)$avatar,
 					'account_id' => $user,
 					'cal_id' => $event['id']
-				], [], $event['start_date'], $event['end_date']);
+				], ['participants' =>array_filter($event['participants'], function($key){return is_numeric($key);}, ARRAY_FILTER_USE_KEY)], $event['start_date'], $event['end_date']);
 			}catch (Exception $e)
 			{
 				//error_log(__METHOD__.'()'.$e->getMessage());