--- title: Blocking Identity Resolution Infrastructure | daily.dev description: Apple and WebKit are blocking network access to third-party identity resolution infrastructure in iOS, iPadOS, macOS, and visionOS 27, countering a post-cookie... canonical: https://daily.dev/posts/blocking-identity-resolution-infrastructure-wz9ikv2fb twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Blocking Identity Resolution Infrastructure | daily.dev og:description: Apple and WebKit are blocking network access to third-party identity resolution infrastructure in iOS, iPadOS, macOS, and visionOS 27, countering a post-cookie... og:url: https://daily.dev/posts/blocking-identity-resolution-infrastructure-wz9ikv2fb og:image: https://api.daily.dev/og/posts/WZ9IKV2Fb.png og:image:alt: Blocking Identity Resolution Infrastructure og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Blocking Identity Resolution Infrastructure **[WebKit](https://daily.dev/sources/webkit)** · 4 min read · 1 upvotes · 0 comments ## Summary Apple and WebKit are blocking network access to third-party identity resolution infrastructure in iOS, iPadOS, macOS, and visionOS 27, countering a post-cookie tracking technique where invisible third parties capture email addresses during login or newsletter signup, link them to a permanent tracking ID, and use that ID to build cross-site, cross-device identity graphs. The blocking happens at the domain level so trackers cannot circumvent it by altering request structure. Apple also points to its Hide My Email feature, available to iCloud+ subscribers, as additional protection since randomized per-site email addresses defeat email-based identity resolution. Apple frames this as a continuation of its long-standing tracking prevention work, distinguishing legitimate first-party personalization from third-party clearinghouse tracking. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What is identity resolution and how does it track users without cookies? Identity resolution is a post-cookie tracking method where third parties invisibly collect a user's email address during login or newsletter signup, send it to their servers, and create a permanent tracking ID linked to that email. The ID is stored on the website and reused across sites and devices to build an identity graph for profiling and ad targeting, even after logout or unsubscribing. _daily.dev surfaces privacy engineering updates for developers tracking how browsers counter identity resolution._ ### How does Safari block identity resolution tracking in iOS, iPadOS, macOS, and visionOS 27? Safari and WebKit block network access to known identity resolution infrastructure at the domain level, preventing these third parties from ever receiving a user's email address. Because blocking happens at the domain level rather than by inspecting request structure, trackers cannot bypass it simply by reformatting network requests. _Developers building ad-tech or login flows can follow browser tracking changes like this on daily.dev._ ### What is Apple's Hide My Email feature and how does it prevent tracking? Hide My Email is an iCloud+ subscriber feature that generates unique, randomized email addresses for each website while still forwarding messages to the user's real inbox. Because each site receives a different address, it defeats email-based identity resolution and cross-site tracking that relies on a shared, persistent email identifier. _daily.dev helps privacy-minded developers stay current on anti-tracking features like Hide My Email._ ## Similar posts on daily.dev - [Apple plans to change its Hide My Email privacy feature that could make it less effective](https://daily.dev/posts/apple-plans-to-change-its-hide-my-email-privacy-feature-that-could-make-it-less-effective-d4e2q67et) · TechCrunch · 0 upvotes · 0 comments - [Apple’s New iPhone Update Is Restricting Internet Freedom in the UK — Big Brother Watch](https://daily.dev/posts/apple-s-new-iphone-update-is-restricting-internet-freedom-in-the-uk-big-brother-watch-ilxopcotb) · Hacker News · 0 upvotes · 0 comments - [Apple rescues Hide My Email feature from the privacy scrap heap](https://daily.dev/posts/apple-rescues-hide-my-email-feature-from-the-privacy-scrap-heap-djrfuf3ha) · TechCrunch · 0 upvotes · 0 comments --- Tags: [#privacy](https://daily.dev/tags/privacy), [#safari](https://daily.dev/tags/safari) [View this post on daily.dev](https://daily.dev/posts/blocking-identity-resolution-infrastructure-wz9ikv2fb) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Blocking Identity Resolution Infrastructure","url":"https://daily.dev/posts/blocking-identity-resolution-infrastructure-wz9ikv2fb","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/blocking-identity-resolution-infrastructure-wz9ikv2fb"},"datePublished":"2026-10-19T17:52:16.359Z","dateModified":"2026-10-19T17:52:38.676Z","description":"Apple and WebKit are blocking network access to third-party identity resolution infrastructure in iOS, iPadOS, macOS, and visionOS 27, countering a post-cookie...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/c931e2df0ce9c131d78e79ae496d99c8?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/c931e2df0ce9c131d78e79ae496d99c8?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"WebKit","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"WebKit","logo":"https://media.daily.dev/image/upload/t_logo,f_auto/v1/logos/webkit","url":"https://daily.dev/sources/webkit"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/blocking-identity-resolution-infrastructure-wz9ikv2fb","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":1},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"privacy,safari","timeRequired":"PT4M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"WebKit","item":"https://daily.dev/sources/webkit"},{"@type":"ListItem","position":3,"name":"Blocking Identity Resolution Infrastructure"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/blocking-identity-resolution-infrastructure-wz9ikv2fb#faq","mainEntity":[{"@type":"Question","name":"What is identity resolution and how does it track users without cookies?","acceptedAnswer":{"@type":"Answer","text":"Identity resolution is a post-cookie tracking method where third parties invisibly collect a user's email address during login or newsletter signup, send it to their servers, and create a permanent tracking ID linked to that email. 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