diff --git a/lib/csv/csv.gemspec b/lib/csv/csv.gemspec
index 9d0ccc15af..6a3435ff9b 100644
--- a/lib/csv/csv.gemspec
+++ b/lib/csv/csv.gemspec
@@ -17,7 +17,7 @@ Gem::Specification.new do |spec|
   spec.homepage      = "https://github.com/ruby/csv"
   spec.license       = "BSD-2-Clause"
 
-  spec.files         = Dir.glob("lib/**/*.rb")
+  spec.files         = ["lib/csv.rb", "lib/csv/table.rb", "lib/csv/core_ext/string.rb", "lib/csv/core_ext/array.rb", "lib/csv/row.rb", "lib/csv/version.rb"]
   spec.files         += ["README.md", "LICENSE.txt", "news.md"]
   spec.require_paths = ["lib"]
   spec.required_ruby_version = ">= 2.3.0"