diff --git a/lib/private/Collaboration/Collaborators/MailPlugin.php b/lib/private/Collaboration/Collaborators/MailPlugin.php
index d28bd3692a4db..3d8914f8630ec 100644
--- a/lib/private/Collaboration/Collaborators/MailPlugin.php
+++ b/lib/private/Collaboration/Collaborators/MailPlugin.php
@@ -68,6 +68,9 @@ public function search($search, $limit, $offset, ISearchResult $searchResult) {
 		$addressBookContacts = $this->contactsManager->search($search, ['EMAIL', 'FN']);
 		$lowerSearch = strtolower($search);
 		foreach ($addressBookContacts as $contact) {
+			if (isset($contact['isLocalSystemBook'])) {
+				continue;
+			}
 			if (isset($contact['EMAIL'])) {
 				$emailAddresses = $contact['EMAIL'];
 				if (!is_array($emailAddresses)) {