/usr/ is in php-horde-lock 2.1.2-1ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/
/usr/share/php/
/usr/share/php/Horde/
/usr/share/php/Horde/Lock.php
/usr/share/php/Horde/Lock/
/usr/share/php/Horde/Lock/Sql.php
/usr/share/php/Horde/Lock/Exception.php
/usr/share/php/Horde/Lock/Null.php
/usr/share/php/Horde/Lock/Mongo.php
/usr/share/php/data/
/usr/share/php/data/Horde_Lock/
/usr/share/php/data/Horde_Lock/migration/
/usr/share/php/data/Horde_Lock/migration/2_horde_lock_upgrade_column_types.php
/usr/share/php/data/Horde_Lock/migration/1_horde_lock_base_tables.php
/usr/share/php/data/Horde_Lock/migration/3_horde_lock_fix_owner_width.php
/usr/share/php/.registry/
/usr/share/php/.registry/.channel.pear.horde.org/
/usr/share/php/.registry/.channel.pear.horde.org/horde_lock.reg
/usr/share/doc/
/usr/share/doc/php-horde-lock/
/usr/share/doc/php-horde-lock/copyright
/usr/share/doc/php-horde-lock/changelog.Debian.gz
/usr/share/doc/php-horde-lock/package.xml.gz