diff --git a/api/go1.txt b/api/go1.txt
index f12719fed6..e6bdd173e9 100644
--- a/api/go1.txt
+++ b/api/go1.txt
@@ -5484,7 +5484,6 @@ pkg regexp/syntax, const ErrMissingBracket ErrorCode
 pkg regexp/syntax, const ErrMissingParen ErrorCode
 pkg regexp/syntax, const ErrMissingRepeatArgument ErrorCode
 pkg regexp/syntax, const ErrTrailingBackslash ErrorCode
-pkg regexp/syntax, const ErrUnexpectedParen ErrorCode
 pkg regexp/syntax, const FoldCase Flags
 pkg regexp/syntax, const InstAlt InstOp
 pkg regexp/syntax, const InstAltMatch InstOp