diff --git a/lisp/elide-head.el b/lisp/elide-head.el
index 30772fa514b..79af01bd480 100644
--- a/lisp/elide-head.el
+++ b/lisp/elide-head.el
@@ -50,16 +50,22 @@
   :group 'tools)
 
 (defcustom elide-head-headers-to-hide
-  `(("is free software[:;] you can redistribute it" . ; GNU boilerplate
+  `(;; GNU GPL
+    ("is free software[:;] you can redistribute it" .
      "\\(If not, see <https?://www\\.gnu\\.org/licenses/>\\|\
 Boston, MA 0211\\(1-1307\\|0-1301\\), USA\\|\
 675 Mass Ave, Cambridge, MA 02139, USA\\)\\.")
+    ;; FreeBSD license
     (,(rx (or "The Regents of the University of California.  All rights reserved."
               "Redistribution and use in source and binary"))
-     . "THE POSSIBILITY OF SUCH DAMAGE\\.") ; BSD
+     . "THE POSSIBILITY OF SUCH DAMAGE\\.")
+    ;; X11 and Expat
     ("Permission is hereby granted, free of charge" .
-     ,(rx (or "authorization from the X Consortium."           ; X11
-              "THE USE OR OTHER DEALINGS IN THE SOFTWARE.")))) ; Expat
+     ,(rx (or "authorization from the X Consortium."          ; X11
+              "THE USE OR OTHER DEALINGS IN THE SOFTWARE."))) ; Expat
+    ;; Modified BSD license (3-clause)
+    ("Redistribution and use in source and binary forms"
+     . "POSSIBILITY OF SUCH DAMAGE\\."))
   "Alist of regexps defining start and end of text to elide.
 
 The cars of elements of the list are searched for in order.  Text is