Intelligent Tracking Prevention: when Apple sets out on a new Safari in the digital advertising wilderness

Data Architecture 8 December 2017

It’s September 12, 2017, the day of the annual Apple keynote. This year, Apple announced the release of its new Operating Systems (High Sierra for Mac, iOS 11 for mobile), which include the usual range of flashy new features. But one newcomer in particular, called Intelligent Tracking Prevention, is turning out to be a true revolution for user data.

This new function, integrated into the native Safari web browser, hunts out cookies by deleting data after a defined amount of time has elapsed: 24 hours for data collected for advertising purposes, and 30 days for data collected for site operation.

Apple has decided to entirely rethink its browser’s cookie management system

When a new user lands on a page, the website’s publisher and its partners distribute a cookie that allows the user to be recognised in the future. Intelligent Tracking Prevention gives advertisers just 24 hours to use the data for advertising means ( display advertising  retargeting campaigns, for example). Once this time is up, Safari breaks the cookie down into two separate files, separating data used for marketing and data that helps the site to work properly. The advertising data file is then deleted from the browser.

The “remaining” cookie, which contains first-party data, is preserved for 29 more days before being deleted in due course if the user does not return to the site within the defined period.


Whether for Mac, iPad, iPhone, or PC, 14% of users prefer Safari*, which means that this shot will be heard all around the digital world.

First, by site publishers. This measure taken by Apple will have consequences on how publishers’ sites operate, as it will mean automatic sign-outs, emptied shopping carts, and deleted wishlists for any users that do not revisit a given site within 30 days. Publishers should also anticipate an impact on webanalytics, particularly audience and engagement indicators, as any Safari users that revisit a given site after the 30-day window will be recorded as new visitors.

For advertisers and advertising players, there will be an immediate consequence on ad campaign measurement. Google has already mentioned the impact on the accuracy of conversion measurement for search campaigns, for example, and has suggested that its clients monitor conversion evolution in the coming weeks. This change also places considerable limitations on retargeting possibilities.

It should be noted that most media tools ( ad server, DMP, attribution, DSP, bid manager, etc.) will be affected, as many of them rely on third-party cookies. There are multiple consequences:

  • In terms of data collection, consequences will be significant particularly concerning conversion attribution and the depth of collected data history for marketing initiatives. This means that all impressions/clicks that occur over 24 hours before the conversion will no longer be taken into consideration in the marketing conversion path, which in turn means that analyses will be less detailed and the attribution will only be based on the past 24 hours. This approach is weaker and oversimplified for products like those in the automotive or e-tourism industry which have longer buying cycles.
    The most impacted channel will certainly be display, which often arrives long before conversions, and generally relies on post impression(post-view) attribution models.
  • In terms of activation, the same applies. Activation (e.g. retargeting via banners) should occur in the day following the initial point of contact between brand and user, which will make the work of some audiences impossible in the long-term. Collecting signals (ad- or site-centric) using a DMP has a 13-month lifespan on other browsers, compared to Safari’s new 24-hour lifespan!
    To preserve their data assets, onboarding CRM players should reconsider the ways they match CRM IDs (usually e-mail address) withcookies, for instance by increasing how often identification and matching occurs within ID matching tables.

Reasonable media consequences considering Safari market shares, but a big impact for digital advertising players

The media impact will be undeniable, but not unbearable in light of Safari’s global market share. However, this will limit knowledge about Safari users who generally have strong buying potential. In terms of the market, this will hurt small players to the benefit of walled gardens that operate in logged spheres such as Facebook or Google. One way of getting around this problem would be to develop logged spheres or combine IDs/cookies that are multi-brand and/or multi-technology to avoid losing data.

This new measure is being loudly criticised by digital advertising players (including the IAB and the ANA) who wrote an open letter accusing the Cupertino company of “overrid[ing] and replac[ing] existing user-controlled cookie preferences with Apple’s own set of opaque and arbitrary standards for cookie handling.” Apple shows no signs of giving in, however, as it dismissed industry complaints and doubled down on its position. Remember that Apple closed its mobile ad network iAd in late 2016, to concentrate its efforts on optimising the user experience (with a focus on privacy).

Now, all web players, site publishers, and advertising solutions must find a way to limit the impact of Intelligent Tracking Prevention on their business.

In the short term, they can use the browser’s free local back up option (or web storage) to preserve first- and third-party data after each visit. All they need to do when the next visit occurs is rebuild the cookies with this data to re-use them. Though an ideal first step, this solution requires a big technical change which could impact both the user experience (slower loading times) and data collection.

A more sustainable solution must be found for the long-term, a goal that professional advertising associations have set for themselves by launching a working group to redefine advertising “Identity Standards”, to find a solution and ensure that data collected online can be used regardless of user browser.

*Browser market share by continent for desktop and smartphone (source)

  • Safari on smartphone: 18%
  • Safari on tablet: 60%
  • Safari on desktop: 5%
  • Safari on all devices: 14%
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