Apple Explains Safari Ban on Companies Converting Emails into Tracking Identities

About a month after cutting off service to user tracking companies in the Safari browser, Apple engineers explained in a blog post published on Monday, October 19, how these companies operate: when a user types their email address on a website, a company working with that site can receive the address and convert it into an identifier that allows advertisers to recognize the same person across different sites without using cookies. LiveRamp, ID5, UID 2.0 (owned by The Trade Desk), Permutive, and Audigent were among the first companies Safari cut ties with when the OS update launched in September, according to Digiday.

Apple said that email addresses have replaced cookies as the anchor for tracking, and that logging out of a site or unsubscribing from a newsletter does not stop it, because the third party retains the tracking code and the email address. With every new login or form submission, the third party adds a detail to what it has gathered, building a profile for each person known in the industry as 'identity graph'. Because Safari strips the target company's full web address, modifying the request-building method does not allow bypassing the block.

Apple did not name any company or explain how a company is added to or removed from its list. It stated that businesses that personalize content for their own customers are not targeted by the ban, whereas third-party companies matching data across sites are targeted. The Trade Desk's ad server was mistakenly blocked alongside UID 2.0 in the early days of the update, but was later reactivated, according to a person familiar with the matter.

The block comes as Apple's advertising business pushes into Maps; Apple has 86 open roles tagged Apple Ads, according to Digiday. The blog post recalls that Safari began removing cookies years ago, and that App Tracking Transparency led many iPhone users to reject tracking, with Meta estimating the cost of that at around $10 billion for 2022. According to Branch data cited by the Financial Times, Apple's share of the iPhone app install ad market rose from 17% to 58% over the same period. Apple declined to comment on hiring and referred to its blog post.

What do these terms mean?

Identity resolution: The process of linking data from different sources to recognize the same person across multiple sites and devices.

Cookies: Small files stored by the browser to remember the user and track their activity across sites.

App Tracking Transparency: A policy from Apple requiring apps to ask for user permission before tracking them across apps and websites owned by other companies.

Identity graphing: A profile in which a third party collects details about a person from every login or form, building a picture of them.