diff --git a/core/regexp.rbs b/core/regexp.rbs
index 32ebef613..fd6d9b102 100644
--- a/core/regexp.rbs
+++ b/core/regexp.rbs
@@ -760,7 +760,7 @@ class Regexp
   #     r3 = Regexp.new(r2)              #=> /cat/i
   #     r4 = Regexp.new('dog', Regexp::EXTENDED | Regexp::IGNORECASE) #=> /dog/ix
   #
-  def initialize: (String string, ?Integer | nil | false options, ?String kcode) -> Object
+  def initialize: (String string, ?Integer | nil | false | top options, ?String kcode) -> Object
                 | (Regexp regexp) -> void
 
   # <!--