A lot of my sales inquiries recently are about getting good inbox delivery at Gmail. I’ve mentioned before, I can usually tell when an ISP changes things because they suddenly become the subject of a great many phone calls.

In this case, Gmail seems to have turned up their engagement filters and is sending a lot more mail to the bulk folder. I have also noticed other people are blogging about Gmail delivery problems. Al eventually determined that it was mailings sent from other IPs that were degrading the delivery of his customer’s emails.

Gmail, more than the other major ISPs, seems to not be weighting IP reputation very heavily these days. They’re looking at domain reputation and they’re using all mentions of a domain in that reputation. A lot of senders, some of them spammers, segregate their email streams (acquisition, marketing, transactional) across IP addresses in order to stop poorly performing mails from harming delivery of other emails they’re sending. But Gmail’s current filtering scheme seems designed to focus on domain reputation and minimize the impact of IP reputation.

This is making the Gmail inbox tough to reach for a lot of mailers these days. Even in cases where the mailer isn’t hiring affiliates or actively partitioning mail, if a domain is seen frequently in spam then delivery for that whole domain is hurting. Signing with DKIM and publishing a DMARC record may help. But the reality right now is that there doesn’t seem to be a silver bullet into the Gmail inbox.