I received a response to this from
acrobatusers.comhttp://www.acrobatusers.com/forums/aucbb/viewtopic.php?pid=71772#p71772A
subscription service is being developed (see http://dc.adobe.com ) but
it can't be used to secure PDFs sent for service digital printing, as
the print shop will need the ability to alter the document (for example
to impose pages into the media sizes they print to, add crop marks,
color-match plates, etc). Digital printers therefore invariably demand
that the PDFs they are s...