/usr/ is in libpreludedb-dev 1.0.0-2.1ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/bin/
/usr/bin/libpreludedb-config
/usr/share/
/usr/share/doc/
/usr/share/doc/libpreludedb-dev/
/usr/share/doc/libpreludedb-dev/README
/usr/share/doc/libpreludedb-dev/copyright
/usr/lib/
/usr/include/
/usr/include/libpreludedb/
/usr/include/libpreludedb/preludedb-plugin-format.h
/usr/include/libpreludedb/preludedb-plugin-sql.h
/usr/include/libpreludedb/preludedb.h
/usr/include/libpreludedb/preludedb-sql.h
/usr/include/libpreludedb/preludedb-version.h
/usr/include/libpreludedb/preludedb-path-selection.h
/usr/include/libpreludedb/preludedb-error.h
/usr/include/libpreludedb/preludedb-sql-settings.h
/usr/share/doc/libpreludedb-dev/changelog.Debian.gz
/usr/lib/libpreludedb.so