In May 2018, Facebook announced that it would be launching a Clear History tool, which would give users the ability to delete data that the platform gathers from third-party websites. Then seen as a damage control move in the wake of last year’s Cambridge Analytica scandal, the tool is finally nearing its release as Facebook continues its bid to prioritize data privacy. In the coming months, Facebook will begin rolling out the Clear History feature to users, which will have a potentially significant impact on advertisers. With less data available for targeting built from the Facebook pixel (e.g. Custom Audiences based on visitors to websites or apps), ad targeting could become a little less precise.
Meanwhile, browser makers are rolling out updates of ITP or “Intelligence Tracking Prevention” technology. As of this week, Safari is now having all tracking cookies expire after 24 hours and, following suit, all third-party cookies in Chrome will be easier to clear without resetting logins. Additionally, Chrome is making alternate tracking methods such as browser fingerprinting infeasible. It isn’t yet completely clear what advertising services’ tracking cookies will be classified as first or third party, but since the Facebook pixel relies on cookies, these updates mean the “look back” windows for attributing conversions and retargeting users may be shrinking.
Why Facebook Marketers Shouldn’t Panic About Clear History and ITP Updates
First, the good news. Facebook has assured us we will not need to worry about any data loss occurring in conversion campaigns as a result of the Clear History tool or related opt-outs. If a user opts out of tracking, that user will not be rejecting their actions being tracked as part of an aggregate—only in association back to their personal account for forward-looking purposes.
Also, the new tools will not impact tracking of “on-Facebook” activity, so interest and demographic targets will be unaffected—as will audiences built on video viewer retargeting and engagement retargeting.
Within the greater ecosystem, Facebook and its advertisers may even benefit from these updates in two major ways. First, when users feel safe, they may use the platforms more. Second, platforms such as Google and Facebook that have login data may be more easily able to adapt to ITP. We know that users tend to stay logged into their accounts, which means there is still a good chance of identifying them and serving them customized content without a cookie.
How to Mitigate the Negative Impact on Ad Targeting Capabilities
Where marketers will see a clear impact is attribution windows, especially click-based conversions. View-based attribution will not be affected for most advertisers because by default they are already confined to a one-day window. Just as with changes to Clear History, ITP’s new expiration dates for cookies won’t impact this short window.
For click-based attribution, on the other hand, the impact will vary greatly since only around 50 to 75 percent of key conversions take place within the first day after a click. Optimistically, Facebook and Google users are almost always logged into their devices, so the potential to join data back to a user’s profile is much greater than for a typical advertising network.
Another change we expect is that Facebook pixel-based targeting will become less valuable as some percentage of people clear their histories or opt out of tracking completely. In the case of retargeting, advertisers can expect their audience pools to shrink. Estimates of the size of reduction are hard to make at this time, but if it is large enough, it may cause marketers to reduce website retargeting budgets.
Another important down-funnel audience, pixel-based lookalikes, may also become less effective since they will use smaller samples to define target users. For most advertisers, this can be mitigated by relying more heavily on lookalikes built from customer lists instead of just pixel events.
Many systems that marketers rely on will be more deeply affected by ITP updates:
- A/B testing methods will lose some of their value, since outcomes will be limited to windows too short to be certain of their predictive power.
- Web analytics tools will become less accurate, because Safari users will be forgotten after one day. User counts will thus be overreported, and returning user counts will be underreported. Similar patterns, though likely less drastic, will occur for Chrome users.
- DMPs will be likely to inflate user counts, and may lead marketers to build audiences based on incorrect size estimates.
- Personalization systems that depend on identifying non-logged-in users will also become less impactful, as the ability to identify users may go down.
Many of the unknowns are important details that we will be watching closely in the coming months. Will Chrome treat DCM’s cookies as first or third party? What about the Facebook pixel? And just how easy will Facebook make it to find the new Clear History tool? How intuitive will it be to use, and how many people will use it? For now, marketers will need to keep an eye on new developments and pivot as needed.