diff --git a/activerecord/lib/active_record/insert_all.rb b/activerecord/lib/active_record/insert_all.rb
index 3863b6bfeaf7b0bffaa633ce5a5cebcf31a9a7a2..2dd9c53a451e566373b46fc535e40957ca16ba0d 100644
--- a/activerecord/lib/active_record/insert_all.rb
+++ b/activerecord/lib/active_record/insert_all.rb
@@ -112,8 +112,7 @@ def verify_attributes(attributes)
         end
       end
 
-
-      class Builder
+      class Builder # :nodoc:
         attr_reader :model
 
         delegate :skip_duplicates?, :update_duplicates?, :keys, to: :insert_all