Getting rid of the via at Gmail

There was a question submitted today about the verification process at Gmail.

even though SPF authentication is passed, a via is added to mail sent from a webserver. The return-path is not the same as the visible from field, but there’s no way for me to change it. Does that mean I won’t be able to get rid of the via?

This actually ties in to some research Steve and I did a few months ago about how and when Gmail is displaying the “via” in their interface. We generated 90+ different emails with various From: addresses, Return-Path: addresses and passing and failing with both SPF and DKIM.
After crunching all the numbers down, I created a table with all the conditions.
All of the conditions we measured
As you can see, there were only a very few conditions that generated the “via” display in the Gmail interface. In cases where there was any domain match between the visible from: and the return path, either the exact domain or a subdomain, there was no “via” displayed, even if authentication failed.
But, when we look at the cases where the domain in the Return-Path is unrelated to the visibly displayed From, then we start to see the cases where Gmail displays the “via.”

Matrix looking at when and what via is displayed
Only when there is a domain mis-match and failing authentication is a via displayed.
So the answer to your question is as long as the webserver is a different domain than the visible From: address Gmail will display a via. You may be able to have no via if you provide no authentication, but Gmail does what it calls “best guess” SPF so even that may not work for you.
 

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Yesterday Gmail rolled out some changes to their interface. One of the changes is that they are now showing end users authentication results in the user screen.
It’s really the next step in email authentication, showing the results to the end user.
So how does Google do this? Google is checking both SPF and DKIM. If mail is authenticated and the authentication matches the from address then they display the email as:
mail from steve to me
If we click on “details” for that message, we find more specific information.
full details of message showing signing domain and spf domainIn this case the mail went through our outgoing mailserver to gmail.
Mailed-by indicates that the message passed SPF and that the IP address is a valid source of mail from wordtothewise.com.
Signed-by shows the domain in the DKIM d=. In this case, we signed with the subdomain dt.wordtothewise.com. That’s what happens when you sign using the domain in the From address (or a subdomain of it).
For a lot of bulk senders, though, their mail is signed using their ESP’s domain instead.  In that case Gmail shows who signed the mail as well as the from address.

And when we click on “details” for that message we see:
3rd party signature detailsThis is an email from a sender using Madmimi as an ESP. Madmimi is handling both the SPF authentication and the DKIM authentication.
As an aside, this particular  sender has a high enough reputation that Gmail is offering me an unsubscribe option in their interface.
Gmail is distinguishing between first party and third party signatures in authentication. If the mail is authenticated, but the authentication appears to be handled by a separate entity, then Gmail is alerting recipients to that fact.
What does this mean for bulk senders?
For senders that are signing with a domain that matches their From: domain, there is no change. Recipients will not see any mention of your ESP in the headers.
However, if you are using an ESP that is signing your mail with a domain they own, then your recipients will see that information displayed in the email interface. If you don’t want this to be displayed by Gmail, then you will need to move to first party signing. Talk to your ESP about this. If they’re unsure of how to manage it, you can point them to DKIM Core for an Email Service Provider.
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Gmail help page about authentication results

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