/usr/ is in ruby-messagebus-api 3.0.7+git.20130130.97b34ece.REALLY.1.0.3-2.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/
/usr/lib/ruby/vendor_ruby/
/usr/lib/
/usr/lib/ruby/vendor_ruby/messagebus_ruby_api.rb
/usr/lib/ruby/vendor_ruby/messagebus_ruby_api/
/usr/lib/ruby/vendor_ruby/messagebus_ruby_api/version.rb
/usr/lib/ruby/vendor_ruby/messagebus_ruby_api/errors.rb
/usr/lib/ruby/vendor_ruby/messagebus_ruby_api/messagebus.rb
/usr/share/
/usr/share/doc/
/usr/share/doc/ruby-messagebus-api/
/usr/share/doc/ruby-messagebus-api/copyright
/usr/share/doc/ruby-messagebus-api/changelog.Debian.gz
/usr/share/rubygems-integration/
/usr/share/rubygems-integration/all/
/usr/share/rubygems-integration/all/specifications/
/usr/share/rubygems-integration/all/specifications/messagebus_ruby_api-1.0.3.gemspec