Apple has moved from investigating to active beta testing. On October 5, WebKit’s John Wilander asked The Trade Desk’s Ian Meyers to test a fresh iOS 27.2 beta. Fifteen minutes later, Meyers said he could see changes in build 24B5099f and that The Trade Desk would report back after testing.
The catch: bug 324771 is still marked NEW, with no assignee. The public record does not say whether Apple lifted, narrowed or left the block on adsrvr.org in place.
Why a delivery domain in a blocklist matters
Safari 27 blocks adsrvr.org, which The Trade Desk uses for core ad requests and delivery, through an 11-line WebKit change that consults an unpublished Apple list of unconditionally blockable domains. The list circulating from Meyers contains nine entries, including uidapi.com, adsrvr.org, rlcdn.com and permutive.com.
The practical difference is simple. Losing an identity endpoint weakens targeting and what a bid is worth. Losing a delivery domain removes the ad request entirely for affected iPhone and iPad visitors. Meyers argues the intent is to hard-block post-cookie identity domains, but that adsrvr.org is “The Trade Desk’s core ad request and delivery domain, not identity.”
A useful test: if blocking a domain kills the ad request, treat it as delivery; if it only makes an impression less relevant, treat it as identity. That tells you how fast to escalate.
The status you should check, not guess
Several questions remain open. It is unclear which of the other eight entries moved in the beta, whether the change reaches production iOS 27.2 and what happens on Mac. Keep the Bugzilla thread as your source of truth rather than Reddit chatter.
What to do now
- Audit your ad server, CDN, sync and identity domains to see if any sit on a private blocklist; test them on the iOS 27.2 beta.
- Separate delivery from identity. If one domain powers both, a blocklist hit does double damage.
- Build first-party measurement and server-side paths so Safari blocks don’t erase performance visibility.
The Trade Desk arrives with its own pressure: it cut around 575 jobs, about 15% of its workforce, on September 4 and lost its S&P 500 seat the same day. That makes the delivery-vs-identity distinction more urgent for buyers and publishers watching iPhone supply.
Source: PPC Land
