----- Original Message -----
From: "Daniel Dreymann" <dreymann(_at_)gmail(_dot_)com>
Not to add too much confusion, let us not forget that CAN SPAM
uses the term "sender" solely for what is referred below as "author".
Good point. But I believe CAN-SPAM is concern about who "initiated"  or
the responsible person who has put a message in motion, into play. In
general, that would be the "Sender" regardless of he actually wrote it or
not. Given the technology we have the past 20 years, this is either the RFC
x821 Return Path: or the RFC x822 From: address, thus this is one reason
many feel CAN-SPAM has failed us. I don't agree with that sentiment, but it
is a legitimate concern. In this regard, SENDER is more of a top level
"user" reference of who as actually wrote and/or put the message into play
and has taken responsibility for that message.
ESPs sometime consider themselves "senders" while their clients on behalf
whom they send are "mailers".
In my decades of writing, producting and marketing mail/data distribution
software, we have never used the term "MAILER" to refer to the CLIENT/AUTHOR
of the message if that the connotation you are referring too. A MAILER is
"SOFTWARE" and more associated with the the transport/frontend system.
Hector Santos, Santronics Software, Inc.
 From CAN-SPAM:
(A) IN GENERAL.-Except as provided in subparagraph
(B), the term ''sender'', when used with respect to a
commercial electronic mail message, means a person who
initiates such a message and whose product, service, or
Internet web site is advertised or promoted by the message.
(B) SEPARATE LINES OF BUSINESS OR DIVISIONS.-If an
entity operates through separate lines of business or divisions
and holds itself out to the recipient throughout the
message as that particular line of business or division
rather than as the entity of which such line of business
or division is a part, then the line of business or the
division shall be treated as the sender of such message
for purposes of this Act.
NOTE WELL: This list operates according to