diff --git a/lisp/gnus/gnus-registry.el b/lisp/gnus/gnus-registry.el
index f306889a7f..72f5938944 100644
--- a/lisp/gnus/gnus-registry.el
+++ b/lisp/gnus/gnus-registry.el
@@ -234,6 +234,14 @@ gnus-registry-max-entries
   :type '(radio (const :format "Unlimited " nil)
                 (integer :format "Maximum number: %v")))
 
+(defcustom gnus-registry-only-precious-p nil
+  "When non-nil, only save entries with a \"precious\" key.
+Entries are still created when entering a Summary buffer, but
+non-precious entries are deleted when exiting the buffer.  See
+`gnus-registry-extra-entries-precious' for the meaning of
+\"precious\"."
+  :type 'boolean)
+
 (defcustom gnus-registry-prune-factor 0.1
   "When pruning, try to prune back to this factor less than the maximum size.
 
@@ -839,7 +847,8 @@ gnus-registry-find-keywords
 
 (defun gnus-registry-register-message-ids ()
   "Register the Message-ID of every article in the group."
-  (unless (gnus-parameter-registry-ignore gnus-newsgroup-name)
+  (unless (or (gnus-parameter-registry-ignore gnus-newsgroup-name)
+	      gnus-registry-only-precious-p)
     (dolist (article gnus-newsgroup-articles)
       (let* ((id (gnus-registry-fetch-message-id-fast article))
              (groups (gnus-registry-get-id-key id 'group)))