Apple’s recent policy of requiring apps to ask for permission before tracking user behavior was introduced in April. The policy allowed most users to avoid being tracked, which meant that advertisers had less insight into how to reach their target audiences. For example, a men’s underwear brand would have no idea whether its ads were reaching men or women. In turn, advertisers cut spending on some of the world’s largest social media platforms and redirected their budgets to users of Android devices and to Apple’s own ad business. 

The almost $10 billion loss translates into 12% of third- and fourth-quarter revenue for top social media companies, ad tech company Lotame told the FT. Facebook’s large size led to the most total revenue loss.

But it was smartphone-focused platform Snap that was impacted the most by Apple’s change, losing 13.2% of the revenue it would have collected otherwise. Earlier this year, Snap shares dropped after the company said it wouldn’t be able to estimate the impact of Apple’s new rules. Last month, Snap’s stock dropped again—22%—just after it reported revenue that fell short of analyst forecasts.

In the hours after that earnings report, spooked investors sent shares in all online ad-based companies plummeting. The selloff wiped $142 billion from the market values of those companies, though many of their shares have since rebounded somewhat.

In any case, services like Facebook may have to come up with entirely new business strategies as a result of Apple’s change, especially as advertisers find effective, cheaper alternatives like TikTok, experts told the FT. Meanwhile, companies like Google parent Alphabet and Twitter were less affected by the decision because their ads do not depend as heavily on tracking mobile habits.  

Mark Zuckerberg openly criticized Apple’s new ad-tracking policy in a third-quarter earnings call last week, saying that Apple’s changes negatively impact not only Facebook but also “millions of small businesses in what is already a difficult time for them in the economy.”

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