What ISPs Think About Your Email

The fourth session of IN: The Email Reputation Conference featured a panel of speakers from ISP’s Comcast and Time Warner/Roadrunner. The conversation started with some statistics about the mail that an average ISP receives. For many, these were surprising numbers, as most marketers didn’t realize the discrepancies in volume between legitimate and illegitimate senders:

Of all mail received:
46% Illegitimate Senders
34% Unknown Senders
20% Legitimate Senders

Average complaint rates by mail server types:
4% Illegitimate Senders
2.6% Unknown Senders
2% Legitimate Senders
1% Known Commercial Senders

The discussion quickly became rousing, with interest piqued by the potential insights the often elusive ISP’s could provide. The conference attendees actively peppered the panelists with a variety of questions, eager to take advantage of the rare opportunity to speak directly with the service providers. The most heated discussions centered on:

Spam Traps:
Marketers focused heavily on gaining a greater understanding of the use of spam traps in determining delivery of mail. The ISPs made it clear that ONLY ISPs or Blacklist owners use spam traps, dispelling myths that those with malicious intent operated these honeypots. The ISPs also made it clear that they WANT to help legitimate marketers get mail delivered, and offer feedback loops for that purpose. They stressed the importance of marketers acting on that feedback (for example: immediately removing unknown users from their mail files) to maximize the data – and increase delivery metrics.

Campaign Elements:
Many participants were highly interested to gain insight into the campaign elements that could possibly be detrimental to delivery. ISPs were quick to dispel myths that both creative content and subject line keywords played a significant role in blocking mail delivery. Consistent with the theme of the day, they stressed the importance of reputation – – having a positive sending history – – which had a much greater weight in the determination of whether or not mail is delivered than content or keywords.

With several audience questions and many sidebar discussions, the session went well over the allotted time and spilled over into hallway conversations during the break. The insight these ISPs provided was quite valuable – and welcome feedback – to those in attendance.

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