diff --git a/parser.ypp b/parser.ypp
index 2afbcac..baa9cab 100644
--- a/parser.ypp
+++ b/parser.ypp
@@ -7,8 +7,6 @@
  * of patent rights can be found in the PATENTS file in the same directory.
  */
 
-%require "3"
-
 %skeleton "lalr1.cc"
 
 %defines