More info about Gmail image caching

A lot of people are discussing the new Gmail image caching around the web.
This doesn’t yet appear to be rolled out across all of Google’s network, so some people in different parts of the world are reporting different behaviors. This is leading to a little bit of confusion, as folks are reporting things like seeing multiple opens for a single image. These reports are clearly accurate, but may only be an artifact of a slow rollout across the network.
There are a couple bullet points I think are important.

  • This does not affect tracking of the first email open as the cache fetches the image from the sender.
  • This does affect tracking if someone opens an email more than once as the email client is pulling images from the Google cache.
  • This does affect geolocation detection as Google is not providing any information about where the open happened.
  • This does affect user agent detection as Google is not providing any information about the original user agent string.
  • This does affect device detection as most of that is done by detecting the user agent.

Derek Harding tested whether or not Google was respecting the expires or no-cache headers. He served images with headers including

Cache-Control: no-cache, no-store, must-revalidate
Pragma: no-cache
Expires: 0

but Google still cached the image.
Right now there doesn’t seem to be any way to bypass the image caching step. I am also not sure how this is affecting people reading mail on standard mail clients (mail.app) or apps on mobile devices.
Other articles discussing the Gmail image caching
Zettasphere: Google Gmail change Breaks Email Open Tracking
ExactTarget: Gmail Now Caching Images
MailChimp: How Gmail’s Image Caching Affects Open Tracking
EmailExpert: Gmail Breaks Email Marketing Again
Frenzy Commerce: Gmail image changes: everything email marketers need to know

Related Posts

Are the new Gmail ads email?

I’ve seen lots of opinions over the last few weeks about whether or not the new ads in the Gmail promotions tab are email or not.

Read More

Do Gmail tabs hurt email marketing?

Earlier this year, Gmail rolled out a new way for users to organize their inbox: tabs. Tabs were an attempt by Gmail to help Gmail users organize their mail, particularly programmatically generated email like social media alerts and marketing mail. While many of us took a wait and see approach, a number of email marketers took this as one of the 7 signs of the apocalypse and the end of email marketing as we know it.
Dozens of marketers wrote article with such titles as “7 ways to survive Gmail tabs” and headlines that declared “Thanks to Gmail’s new tabs, promotional e-mails are now shunted off to a secondary inbox. If you rely on e-mail marketing, you should be worried.” Marketers large and small responded by sending emails to recipients begging them to move marketing mail out of the promotions tab and into the inbox.
A number of bloggers, reporters and marketers, myself included, tried to tame the panic. Not because we necessarily supported tabs, but because we really had no insight into how this would affect recipients interacting with email.
This week Return Path published a whitepaper on the effect of Gmail tabs on email marketing (.pdf link).
Not only did Return Path’s research show little negative effect of tabs, they actually saw some positive effects of tabs on how recipients interact with commercial email. Overall, the introduction of tabs in the gmail interface may be a improvement for email marketers.

Read More

Gmail says no expectation of privacy, kinda.

Consumer Watch put out a press release yesterday about a court filing made by Gmail that says Gmail users have no expectation of privacy. I pulled a bunch of the docs yesterday, but have had no real time to read or digest them.
For recap users everything I pulled (and stuff other people have pulled) are available at Archive.org.
The initial complaint was filed under seal at the request of Google. The redacted complaint doesn’t tell us a lot, but it’s available for people to read if they’re interested.
The doc everyone is talking about is Google’s Motion to Dismiss. Everyone is up in arms about Google saying, in that filing, “a person has no legitimate expectation of privacy in information he voluntarily turns over to third parties.” (page 28, line 9). What no one seems to have mentioned is that this is actually a quote from a case that Google is referencing. The whole paragraph may lead one to a different conclusion.

Read More