diff --git a/lib/grape/dsl/parameters.rb b/lib/grape/dsl/parameters.rb
index e298a747d..1ad89d3e7 100644
--- a/lib/grape/dsl/parameters.rb
+++ b/lib/grape/dsl/parameters.rb
@@ -141,7 +141,7 @@ def optional(*attrs, **opts, &block)
         opts = @group.deep_merge(opts) if @group
 
         # check type for optional parameter group
-        if attrs && block
+        if block
           raise Grape::Exceptions::MissingGroupType if type.nil?
           raise Grape::Exceptions::UnsupportedGroupType unless Grape::Validations::Types.group?(type)
         end
diff --git a/lib/grape/router.rb b/lib/grape/router.rb
index 3dcdf08f6..457b9b62c 100644
--- a/lib/grape/router.rb
+++ b/lib/grape/router.rb
@@ -135,7 +135,7 @@ def with_optimization
     end
 
     def default_response
-      [404, DEFAULT_RESPONSE_HEADERS.dup, DEFAULT_RESPONSE_BODY.dup]
+      [404, DEFAULT_RESPONSE_HEADERS.dup, DEFAULT_RESPONSE_BODY]
     end
 
     def match?(input, method)