+ ``--deduplicate=(no|mailbox)``
+
+ Control the deduplication of results.
+
+ **no**
+ Output all occurences of addresses in the matching
+ messages. This is not applicable with --output=count.
+
+ **mailbox**
+ Deduplicate addresses based on the full, case sensitive
+ name and email address, or mailbox. This is effectively
+ the same as piping the --deduplicate=no output to **sort |
+ uniq**, except for the order of results. This is the
+ default.
+