/usr/share/horde/nag/lib/Form/ is in php-horde-nag 4.2.1-4.
This file is owned by root:root, with mode 0o755.
..
/usr/share/horde/nag/lib/Form/CreateTaskList.php
/usr/share/horde/nag/lib/Form/DeleteTaskList.php
/usr/share/horde/nag/lib/Form/EditTaskList.php
/usr/share/horde/nag/lib/Form/Search.php
/usr/share/horde/nag/lib/Form/Task.php
/usr/share/horde/nag/lib/Form/Type/
/usr/share/horde/nag/lib/Form/Type/NagAlarm.php
/usr/share/horde/nag/lib/Form/Type/NagDue.php
/usr/share/horde/nag/lib/Form/Type/NagMethod.php
/usr/share/horde/nag/lib/Form/Type/NagRecurrence.php
/usr/share/horde/nag/lib/Form/Type/NagSearchDue.php
/usr/share/horde/nag/lib/Form/Type/NagStart.php
/usr/share/horde/nag/lib/Form/Type/NagTags.php