Apple has reopened its long-running fight with ad tech — and this time publishers are already feeling the revenue hit. After the latest iPhone software update, Safari began cutting off network access to identity resolution vendors, the companies that stitch together email addresses, phone numbers, IP addresses and browsing history to track people across sites and devices.
What Apple actually blocked
The update initially stopped The Trade Desk’s ads from loading in Safari. Soon the industry realized ID5, LiveRamp, Permutive, Audigent and UID 2.0 were blocked too. The Trade Desk got a reprieve; the identity vendors did not. Apple stayed quiet through Advertising Week New York, then confirmed in an Oct. 19 blog post that Safari now blocks identity resolution companies from network access.
The publisher damage, in numbers
Aditude data shows how exposed publishers are to WebKit, the browser engine that powers Safari and every browser on iPhones and iPads:
- 30% of ad impressions and 28.5% of ad revenue flow through WebKit.
- Only 3.8% of impressions and 3.3% of Prebid revenue have moved to WebKit so far, but adoption grew by half in a week and new iPhones over the holidays will push it higher.
- iOS bid rates fell 14% between Sept. 15 and Oct. 8, and are since down about 8%.
- Mac bid rates are off about 25% with no sign of recovery.
The result is lower yield: eCPMs are down 4% on iOS and 11% on Macs, while revenue per ad opportunity has fallen 6% and 20% respectively.
Life after the ID
Apple has every incentive to press on: blocking trackers fits the privacy brand it has spent years building. That means marketers and publishers need to get comfortable with contextual and aggregate signals rather than knowing exactly who is behind the screen. OpenX’s U.S. platform data shows the shift is already underway. In 2022, 78% of targeted ad money went to third-party audience data; by 2025 that share was around 40%, with contextual targeting on CTV picking up much of the slack.
Permutive, one of the blocked vendors, frames the debate differently. Its analysis of more than 10 publishers and 569 million winning bids in August found that inventory without IDs sells at an average 42% discount to Chrome. But IDs only cover about 30% of the bid stream, leaving most publisher audiences unsold. Across more than 80 publishers over 12 months, using publishers’ own data lifted CPMs by 76% on direct-sold deals and 32% on private marketplace deals.
Apple’s ads business keeps climbing
The timing is awkward for Apple because its own ad business is growing quietly. eMarketer expects Apple to bring in $9.05 billion in U.S. ad revenue in 2026, rising 15.6% to $10.46 billion in 2027 and 13.8% to $11.9 billion in 2028. Globally, the forecast climbs from $14.48 billion in 2026 to $18.03 billion in 2028. Ads sit inside services, which now contribute 43% of Apple’s gross profit, up from 24% in 2018, according to Enders Analysis.
What marketing teams should do now
For our readers, the near-term playbook is clear. Audit how much of your site or client revenue depends on Safari and WebKit. Rebalance targeting toward contextual signals on CTV and content categories. And treat first-party publisher data as a premium asset in direct and private marketplace deals, where Permutive’s numbers suggest it can meaningfully lift CPMs. The vendors Apple blocked may not come back, and the brands that adapt first will be the ones still reaching Safari readers without paying a penalty.
Source: Digiday
