/usr/lib/ is in libvalidatable-ruby1.8 1.6.7-6.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/
/usr/lib/ruby/1.8/
/usr/lib/ruby/1.8/macros.rb
/usr/lib/ruby/1.8/validatable_class_methods.rb
/usr/lib/ruby/1.8/requireable.rb
/usr/lib/ruby/1.8/child_validation.rb
/usr/lib/ruby/1.8/included_validation.rb
/usr/lib/ruby/1.8/validatable.rb
/usr/lib/ruby/1.8/errors.rb
/usr/lib/ruby/1.8/validatable_instance_methods.rb
/usr/lib/ruby/1.8/understandable.rb
/usr/lib/ruby/1.8/object_extension.rb
/usr/lib/ruby/1.8/validations/
/usr/lib/ruby/1.8/validations/validates_numericality_of.rb
/usr/lib/ruby/1.8/validations/validation_base.rb
/usr/lib/ruby/1.8/validations/validates_acceptance_of.rb
/usr/lib/ruby/1.8/validations/validates_presence_of.rb
/usr/lib/ruby/1.8/validations/validates_length_of.rb
/usr/lib/ruby/1.8/validations/validates_each.rb
/usr/lib/ruby/1.8/validations/validates_format_of.rb
/usr/lib/ruby/1.8/validations/validates_true_for.rb
/usr/lib/ruby/1.8/validations/validates_confirmation_of.rb