Note that all of the birthtime related primaries are non-standard.

usr.bin/find/find.1

@@ -35,7 +35,7 @@
 .\"	@(#)find.1	8.7 (Berkeley) 5/9/95
 .\" $FreeBSD$
 .\"
-.Dd April 3, 2006
+.Dd April 4, 2006
 .Dt FIND 1
 .Os
 .Sh NAME
@@ -865,10 +865,10 @@ All the single character options except
 and
 .Ic -L
 as well as the
-.Ic -iname , -inum , -iregex , -print0 , -delete , -ls ,
-and
-.Ic -regex
-primaries are extensions to
+.Ic -iname , -inum , -iregex , -print0 , -delete , -ls , -regex ,
+and all of the
+.Ic -B
+birthtime related primaries are extensions to
 .St -p1003.1-2001 .
 .Pp
 Historically, the