How Safari’s Intelligent Tracking Prevention (ITP 2.1) Will Affect Web Analytics

Of all the silicon tech companies, Apple is distinguishing itself on Privacy. With Tim Cook stating that Privacy Matters, and the latest update of Safari's Intelligent Tracking Prevention helping them further the cause, marketers should be aware of the implications this new release will have on web analytics. (See Apple’s Privacy commercial here: https://youtu.be/A_6uV9A12ok) In the spirit of privacy, Apple introduced Intelligent Tracking Prevention (ITP) in 2017 as a means of preventing sites to track Safari users cross domain visits via third-party cookies for longer than a 30-day window.   This principally was aimed at AdTech companies who were creating “cookie pools” based on the user’s visitor journey across the web. Google responded with code created to circumvent this 1st version of ITP as it would affect conversion reporting for its AdWords campaigns; users of Google’s Tag Manager were encouraged to create a Tag using this available variable.  Subsequent versions of ITP have since been released, with ITP2.1 now being the latest version.

What is changing:

ITP2.1 has further expanded upon previous versions and now changes how 1st party cookies will be treated. Previously, any persistent client-side cookie had a 30 day expiration, and now they will expire after just 7 days

What this affects:

Not only will this be a challenge for publishers and tech vendors, but since Google Analytics uses a 1st party cookie which is set via javascript on the user’s initial visit, it will also affect advertisers and marketers when reviewing various metrics on site performance and user behavior. Web marketers will often look at month over month comparison for their website visitors to determine new versus returning visitors. Now with ITP 2.1, if a visitor first visits a site on day 1 and then returns to the site the following week on day 8 or later, they will be classified as a new visitor versus a returning visitor. Similarly, if the visitor has come to the site from a campaign and waits until day 8 or later to return for a conversion, the campaign may not receive the attribution it deserves. The Google Analytics reports that could be affected are the Behavior reports:

• New vs Returning and Frequency & Recency
• Cross-Device
• Device Overlap and Device Paths
• Conversions
• Multi-Channel Funnels

Why this change was made:

Early versions of ITP affected 3rd party cookies, such as those used by AdTech companies to build cookie pools based on cross-domain tracking; however, 1st party cookies were left alone.  Apple discovered that some AdTech vendors (such as Facebook) started repurposing the 1st party cookie to help with their own cross-domain tracking intentions. Apple’s intention in expanding the scope of their ITP is directed towards user privacy and to limit the risk inherent when secure cookie protocols are not being used. Sites which require users to log in and set a unique User Id will generally not be affected, at least with respect to monthly new / return user analysis.

When does this change go into effect:

This will be implemented with the IOS 12.2 update which Apple has started pushing via its auto-update feature.

How to judge potential impact:

A good starting point is to determine what overall percentage of your website visitors are using Safari. Next, look at your Frequency & Recency report to see what percentage of these Safari visitors are returning after 7 days. As an example in reviewing one of Primacy's clients' reports, we see that their Safari visitors represent slightly over 43% of their sessions yet only 9% of these visitors return to this site 8 days or later; just 4% in the window of 8 – 30 days. So while this client has significant Safari visitor share, the majority of these visits are still occurring within the 7 day cookie window.

What else to expect:

Firefox is reportedly also going to be implementing its own version of ITP 2.1 which will supplement the private browsing feature it already has.