Index: share/man/man9/style.9
===================================================================
--- share/man/man9/style.9
+++ share/man/man9/style.9
@@ -134,7 +134,15 @@
 in front of foreign VCS IDs if the file is renamed.
 .Bd -literal
 /* From: @(#)style	1.14 (Berkeley) 4/28/95 */
-
+.Ed
+If your code needs to be merged into stable/12 or earlier, it
+needs to have the
+.Dq $FreeBSD$
+tag.
+Otherwise this tag should be omitted in new code.
+Legacy code will have the tag removed in the future once
+stable/12 is no longer supported.
+.Bd -literal
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 .Ed