> On Oct 2, 2017, at 11:47 AM, Noel Jones <njo...@megan.vbhcs.org> wrote: > > Note this may *severely* delay deliveries, depending on the sender's > retry policy. If a message arrives with 100 recipients, the sender > will need to retry 99 times, which will likely take a very long time.
It violates SMTP standards. Interoperable SMTP servers are required to accept up to 100 recipients per envelope (message delivery). Do not cripple SMTP. Make sure your anti-abuse measures do not impede legitimate email. Avoid techniques that impose behaviour changes on legitimate email senders. -- Viktor.