In May 2018 Mark Zuckerberg promised the launch of Facebook Clear History: “A simple control to clear your browsing history on Facebook – what you’ve clicked on, websites you’ve visited, and so on.”

Facebook CFO David Wehner on Tuesday – speaking the Morgan Stanley Technology, Media & Telecom Conference 2019 in San Francisco – said Facebook will finally launch the feature later this year.

The commercial impact could be notable for Facebook’s advertiser base of over seven million companies, if consumers adopt it widely.

Facebook Clear History: Ad Targeting to be Affected

While it may be relished by users, for whom clearing their history is currently a laborious, painstaking task, Wehner said the feature will hit Facebook’s ability to use data collected by third parties to target ads.

As CNBC reports: “[clear history is] going to give us some headwinds in terms of being able to target as effectively as before,” Wehner said.

It remains to be seen quite how significant the impact could be. It seems unlikely to dent Facebook’s relentless ad growth: Q4 mobile ad revenue alone was $15.5 billion (up 36 percent year-on-year).

Read this: GDPR “Saved” Email Marketing (But Cookie Opt-Outs Surged)

Advertisers often work with third-party marketing services such as Axiom, Datalogic or Epsilon to find the right customer.

These companies use a variety of data sources such as credit card information, consumer behaviour and more to provide information that can be integrated with Facebook to target adverts at a user.

Facebook Clear History will be a comprehensive cookie-wipe that could impact the ability of these tools to work together, from what Zuckerberg’s post suggests, although full details remain thin on the ground.

As he described it: “Once we roll out this update, you’ll be able to see information about the apps and websites you’ve interacted with, and you’ll be able to clear this information from your account. You’ll even be able to turn off having this information stored with your account.”

The decision comes after Facebook on October 24 last year introduced “first-party” cookies that allow it to track users even if someone is accessing a website via a browser that blocks third-party cookies.

As Facebook put it at the time: “We are offering a first-party cookie option for the Facebook pixel to help businesses continue understanding site activity and ad attribution across browsers. This change is in line with updates made by other online platforms, as the use of first-party cookies for ads and analytics is becoming the preferred approach by some browsers.”

The extent to which Clear History offsets any gains resulting from this move will depend, of course, now just how many users feel the need to regularly clear their Facebook history…

Shane Phair, Chief Marketing Office of Campaign Monitor told Computer Business Review in an emailed statement: “Regardless of channel, customers should never have to worry about their personal information being misused by marketers.”

“The implementation of policies and tools such as GDPR, cookie opt-outs, and now the Facebook Clear History Tool are all steps forward to help users regain and maintain control of their shared data. These changes will inevitably force companies to change their promotional strategies and tactics. The email marketing industry was one of the first to do so and as a result, we’ve seen a positive impact on subscriber engagement, customer trust and the overall quality of marketing efforts.”