Earlier this year, Apple announced a sizeable change to how its Safari browser manages site cookies. An update to the previous Intelligent Tracking Prevention (ITP) 2.0, ITP 2.1 is already having an impact on the ability of advertisers to track performance across Apple devices.

Background to Intelligent Tracking Prevention

In June 2018, Apple announced ITP 2.0 for its Safari web browser (used by iPhones, iPads and Macs). It blocked 3rd Party cookies, which prevented advertisers from tracking conversions, remarketing and distinguishing between new and returning website users.

By not being able to attribute conversions, advertisers had no visibility on the effectiveness of their activity on Safari, the World’s second most popular web browser.

The good news is that the three biggest ad platforms - Google, Bing and Facebook - quickly came up with solutions to continue tracking conversions and remarket to Safari visitors. The solutions shifted the cookies that they had previously used from 3rd party cookies, to 1st party cookies (client-side), that were unaffected by ITP 2.0.

What’s Intelligent Tracking Prevention 2.1?

Fast forward to February 2019 and Apple has announced ITP 2.1. While it introduced a number of updates, the most important change is that all persistent, client-side (1st Party) cookies can now only be stored for a maximum of 7 days.

Apple have said that the reason for the change was to address privacy, security and performance concerns. In simple terms, it reduces the ability of advertisers to establish user identity across sites.

The update is already live on Macs, and iPhone and iPads will follow suit when the latest iOS update is released (believed to be before the end of March 2019). You can read the full technical specifications of ITP 2.1 here...

How Does It Affect You?

The seven-day cap on first party cookies will have the greatest impact on websites with long conversion paths. For instance, travel websites and those with big ticket, high involvement purchases will be worst off.

These websites are likely to see an increase in ‘Direct’ conversions and a decline in all other attributed conversions. Additionally, remarketing lists will be limited to a 7-day period and there will be a decline in ‘Returning Users’ within GA.

It’s key to remember that only users with a Safari browser will be impacted; although this is likely to be a significant amount of your traffic. You can easily see what volume of your visitors this will be, by looking at the ‘Browser’ report in Google Analytics (Audience > Technology > Browser & OS).

We looked at a cross section of our clients and found that the percentage of sessions on Safari ranged from 30-55%.

Will There Be a Fix?

Google, Bing and Facebook have yet to announce a fix for ITP 2.1, but the likely move will be to utilise local storage rather than cookies. This could mean that, once again, there will be little or no real impact for clients. However, as Apple were so quick to eliminate the 1st party loophole, it’s safe to assume that, at some stage, they will do the same with any fix that the major ad platforms roll out.