This new feature is a setting for Apple’s mail app that will be added in iOS 15, iPadOS 15, MacOS Monterery, and watchOS 8. Apple has not yet revealed too much detail about its inner workings. But industry experts believe that the approach will be similar, if not identical, to what Google already does with Gmail. All images within an email are automatically downloaded by Google’s proxy servers. When recipients open their emails in Gmail, the images they see are coming from Google’s proxy servers, not from the original source.

This prefetching feature only applies to users who read their emails in the Apple mail app regardless of who their mailbox provider is (e.g. iCloud, Gmail, Yahoo, etc.). However, email apps other than the Apple mail app (e.g. Gmail email app on iPhone) are unaffected.

The immediate impact of the Mail Privacy Protection feature is that every email sent to recipients who use the Apple mail app to read their emails will appear as “opened” regardless of whether or not the email was actually read by the recipient. In addition, the IP address associated with that open event will be the location of Apple’s proxy servers, and not of the recipient who read the email. The exact user agent returned by the proxy servers when fetching the images is still unknown until further testing can be conducted.

Email open rates are expected to increase substantially. The pre-fetching of all images within an email (including the open tracking pixel) means that every email will be registered as “opened” no matter what.

Click-to-Open rates are expected to decrease substantially. The number of actual clicks divided by a higher number of opens depresses the numerical value of the fraction.

Percentages of desktop vs. mobile opens will shift substantially. Email service providers rely on the user agent that is sent from the email client when asking for the email’s images. The user agent returned by Apple’s proxy servers will not accurately convey whether the recipient read the email on a Macbook Pro versus an iPhone.

The number of emails sent in a campaign will substantially shift. If the campaign is targeted to contacts who have opened recently, then the number of emails sent will dramatically increase compared to previous emails. If the campaign is using a suppression segment based on contact who have opened recently, then the number of emails sent will dramatically decrease compared to previous emails.

Geo-targeting segment rules will have to be re-evaluated. Currently Maropost stores the IP addresses of contacts when they open an email. When targeting contacts in a certain geographical region, email marketers should be aware that some contacts will not receive the intended campaigns, while others who shouldn’t receive the email will. It is uncertain yet as to what range of IP addresses Apple’s proxy servers will be using when pre-fetching email images.

A|B Test Campaigns will need to be adjusted. It is possible that A|B Campaigns using email open rates will result in the wrong winning test group. If Apple mail app contacts are homogeneously distributed between each of the test groups, then there will be no material change. However, if one of the test groups has a higher distribution of Apple mail contacts, then the open rate will be artificially higher for that test group.

In similar (though reverse) manner, A|B Campaigns using click-to-open reates to decide the winner may likewise result in the wrong test group being named the winner. In this case, a test group with a higher distribution of Apple mail app contacts will result in a lower click-to-open rate causing it to NOT be selected as the winner, when in fact given real opens, it might have been.

Automated Journey Campaigns will need to be re-examined. Automated campaigns that use a filter based on whether or not a contact has opened a prior email may end up directing a contact down the wrong branch of the flow. The end result will be contacts receiving the wrong emails, too many emails, or no emails at all.
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Send-Time Optimization and Timezone Optimization campaigns will become less reliable. Send-time optimization is based on when the contact reads the email. Timezone optimization is based on the source IP address of the contact’s computer (or mobile device) that was used to read the email. The purpose of Mail Privacy Protection is to obfuscate from the email service provider’s platform when and where the contact was when reading the email.

It can be argued that it's making GDPR and eprivacy compliance more difficult. "Under eprivacy and GDPR there is a requirement for data controllers to be able to demonstrate that consent or permission is still active and the data can still be used for that purpose. That's significantly more difficult if the sender cannot implement a data lifecycle based on engagement," says Dennis Dayman, Chief Privacy Officer at Maropost.

Now more than ever is the time to start thinking about measuring success for marketing campaigns based on sales/conversion rates, rather than clicks and opens. The point of email marketing is to motivate the recipients to respond to your email's call to action, not just get them to open it.

This is also a good thing for marketers who are integrating their eCommerce platforms with their marketing automation platforms. You'll want to get a good set of baseline metrics today that can be used for performance tracking once opens are a thing of the past. In the future, instead of open rates, you can try combining conditions like recency of sign up, purchase, on-site behavior, and email conversions (i.e. e-commerce).

The Mail Privacy Protection feature also opens the door for a compelling value proposition for inbox placement reporting tools like Validity's Everest, Maropost's InboxAware, and others. As email open rates become less and less reliable as indicators of the health, senders can still triangulate reader engagement by plenty of metrics that are still available to them, including the views their stories get on the web, the overall growth of their mailing list, and — most meaningful of all — the growth of their revenue. This does mean that monitoring inbox placement and blocklist monitoring will become an even more crucial metric to track because assuming your emails have landed in the inbox based on opens will no longer be reliable.