diff --git a/api/setup/setup.inc.php b/api/setup/setup.inc.php
index 0758b549b4..2294ca83de 100644
--- a/api/setup/setup.inc.php
+++ b/api/setup/setup.inc.php
@@ -11,7 +11,7 @@
 /* Basic information about this app */
 $setup_info['api']['name']      = 'api';
 $setup_info['api']['title']     = 'EGroupware API';
-$setup_info['api']['version']   = '20.1.001';
+$setup_info['api']['version']   = '20.1.002';
 $setup_info['api']['versions']['current_header'] = '1.29';
 // maintenance release in sync with changelog in doc/rpm-build/debian.changes
 $setup_info['api']['versions']['maintenance_release'] = '20.1.20201005';
@@ -141,3 +141,4 @@ $setup_info['groupdav']['license'] = 'GPL';
 $setup_info['groupdav']['hooks']['preferences']	= 'EGroupware\\Api\\CalDAV\\Hooks::menus';
 $setup_info['groupdav']['hooks']['settings']	= 'EGroupware\\Api\\CalDAV\\Hooks::settings';
 
+
diff --git a/api/setup/tables_current.inc.php b/api/setup/tables_current.inc.php
index 9c5f443216..ed0e42d763 100644
--- a/api/setup/tables_current.inc.php
+++ b/api/setup/tables_current.inc.php
@@ -518,11 +518,12 @@ $phpgw_baseline = array(
 			'shared_with' => array('type' => 'int','meta' => 'account','precision' => '4','nullable' => False),
 			'shared_by' => array('type' => 'int','meta' => 'user','precision' => '4','nullable' => False),
 			'shared_at' => array('type' => 'timestamp','nullable' => False,'default' => 'current_timestamp'),
-			'shared_writable' => array('type' => 'bool','nullable' => False,'default' => '0')
+			'shared_writable' => array('type' => 'bool','nullable' => False,'default' => '0'),
+			'shared_deleted' => array('type' => 'timestamp','comment' => 'timestamp, if deleted')
 		),
 		'pk' => array('shared_id'),
 		'fk' => array(),
 		'ix' => array('contact_id','shared_with'),
-		'uc' => array()
+		'uc' => array(array('shared_by','shared_with','contact_id'))
 	)
 );
diff --git a/api/setup/tables_update.inc.php b/api/setup/tables_update.inc.php
index 65867c8174..e83e33c123 100644
--- a/api/setup/tables_update.inc.php
+++ b/api/setup/tables_update.inc.php
@@ -753,3 +753,19 @@ function api_upgrade20_1()
 
 	return $GLOBALS['setup_info']['api']['currentver'] = '20.1.001';
 }
+
+/**
+ * Add deleted timestamp and unique index for contact sharing
+ *
+ * @return string
+ */
+function api_upgrade20_1_001()
+{
+	$GLOBALS['egw_setup']->oProc->AddColumn('egw_addressbook_shared','shared_deleted',array(
+		'type' => 'timestamp',
+		'comment' => 'timestamp, if deleted'
+	));
+	$GLOBALS['egw_setup']->oProc->CreateIndex('egw_addressbook_shared', array('shared_by','shared_with','contact_id'), true);
+
+	return $GLOBALS['setup_info']['api']['currentver'] = '20.1.002';
+}