/usr/share/php/Horde/ is in php-horde-notification 2.0.4-3ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/php/Horde/Notification/
/usr/share/php/Horde/Notification.php
/usr/share/php/Horde/Notification/Event/
/usr/share/php/Horde/Notification/Event.php
/usr/share/php/Horde/Notification/Event/Status.php
/usr/share/php/Horde/Notification/Exception.php
/usr/share/php/Horde/Notification/Handler/
/usr/share/php/Horde/Notification/Handler.php
/usr/share/php/Horde/Notification/Handler/Decorator/
/usr/share/php/Horde/Notification/Handler/Decorator/Alarm.php
/usr/share/php/Horde/Notification/Handler/Decorator/Base.php
/usr/share/php/Horde/Notification/Handler/Decorator/Log.php
/usr/share/php/Horde/Notification/Listener/
/usr/share/php/Horde/Notification/Listener.php
/usr/share/php/Horde/Notification/Listener/Audio.php
/usr/share/php/Horde/Notification/Listener/Status.php
/usr/share/php/Horde/Notification/Storage/
/usr/share/php/Horde/Notification/Storage/Interface.php
/usr/share/php/Horde/Notification/Storage/Object.php
/usr/share/php/Horde/Notification/Storage/Session.php