{"id":438,"date":"2026-09-10T11:05:52","date_gmt":"2026-09-10T09:05:52","guid":{"rendered":"https:\/\/www.lukaswojcik.com\/?p=438"},"modified":"2026-09-10T11:05:52","modified_gmt":"2026-09-10T09:05:52","slug":"the-post-cookie-era-inside-topics-api-and-protected-audience-in-google","status":"publish","type":"post","link":"https:\/\/www.lukaswojcik.com\/blog\/en\/data-privacy\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\/","title":{"rendered":"The Post-Cookie Era: Inside Topics API and Protected Audience in Google Privacy Sandbox"},"content":{"rendered":"\r\n<p class=\"wp-block-paragraph\">The deprecation of third-party cookies across modern web browsers fundamentally restructures how digital advertising, remarketing, and audience analytics operate. Without shared deterministic identifiers stored in third-party HTTP contexts, cross-site tracking via central ad servers is no longer viable. In its place, the Google Privacy Sandbox introduces a paradigm where the individual web browser assumes responsibility for interest categorization and auction orchestration through APIs such as the Topics API and the Protected Audience API.<\/p>\r\n\r\n\r\n\r\n<h2 class=\"wp-block-heading\">1. The Architectural Shift Away from Third-Party Cookies<\/h2>\r\n\r\n\r\n\r\n<p class=\"wp-block-paragraph\">In traditional advertising pipelines, third-party cookies allowed ad networks to track browsing histories across unrelated domains, building centralized behavioral profiles on external servers. The Privacy Sandbox flips this data architecture from a server-side tracking model to an on-device computation model. Raw browsing history remains exclusively within the local browser storage, while standardized APIs expose only privacy-preserving, aggregate, or noise-injected signals to authorized ad tech platforms.<\/p>\r\n\r\n\r\n\r\n<figure class=\"lw-diagram\">\n<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.lukaswojcik.com\/blog\/wp-content\/uploads\/diagrams\/privacy-sandbox-topics-protected-audience-en.png\" width=\"1120\" height=\"580\" alt=\"Privacy Sandbox flow with Topics API classification per epoch and the on-device Protected Audience auction ending in a fenced frame\">\n<figcaption>Both mechanisms move what used to happen on ad servers into the browser: the interest classification runs per weekly epoch on the device, and the auction is decided locally before the winning ad is sealed into a fenced frame.<\/figcaption>\n<\/figure>\r\n\r\n\r\n\r\n<h2 class=\"wp-block-heading\">2. Topics API: Coarse-Grained On-Device Interest Profiling<\/h2>\r\n\r\n\r\n\r\n<p class=\"wp-block-paragraph\">The Topics API replaces granular behavioral tracking by assigning coarse-grained interest categories directly within the browser based on recent navigation patterns:<\/p>\r\n\r\n\r\n\r\n<ul class=\"wp-block-list\">\r\n<li><strong>Local Epoch Classification:<\/strong> During weekly epochs, the browser analyzes visited hostnames and maps them to a human-curated taxonomy of interest categories (e.g., &#8220;Autos &amp; Vehicles&#8221;, &#8220;Consumer Electronics&#8221;).<\/li>\r\n<li><strong>Restricted Signal Exposure:<\/strong> When an ad tag queries the Topics API via JavaScript (using <code>document.browsingTopics()<\/code>), the browser returns up to three topics\u2014one from each of the preceding three weekly epochs.<\/li>\r\n<li><strong>Noise Injection &amp; Privacy Budgets:<\/strong> To prevent fingerprinting, a random topic from the taxonomy is returned in 5% of API evaluations, ensuring deterministic re-identification of individuals across origins remains mathematically infeasible.<\/li>\r\n<\/ul>\r\n\r\n\r\n\r\n<h2 class=\"wp-block-heading\">3. Protected Audience API: On-Device Ad Auctions for Retargeting<\/h2>\r\n\r\n\r\n\r\n<p class=\"wp-block-paragraph\">Formerly known as FLEDGE, the Protected Audience API enables custom audience retargeting without sharing site-visitation history with third parties. The entire bidding and auction logic executes within isolated browser environments:<\/p>\r\n\r\n\r\n\r\n<h3 class=\"wp-block-heading\">Interest Group Management<\/h3>\r\n\r\n\r\n\r\n<p class=\"wp-block-paragraph\">When a visitor interacts with specific products or conversion funnels, a website tag instructs the browser to join an Interest Group (using <code>navigator.joinAdInterestGroup()<\/code>). The browser stores the group name, owner domain, and bidding script URLs locally.<\/p>\r\n\r\n\r\n\r\n<h3 class=\"wp-block-heading\">In-Browser Auction Orchestration<\/h3>\r\n\r\n\r\n\r\n<ul class=\"wp-block-list\">\r\n<li><strong>Isolated Bidding Worklets:<\/strong> On a publisher site, the browser executes bidding scripts inside isolated JavaScript worklets without network access, evaluating ad relevance without leaking user state.<\/li>\r\n<li><strong>Fenced Frames Rendering:<\/strong> The winning advertisement is rendered inside a secure <code>&lt;fencedframe&gt;<\/code> HTML element. This restricted container isolates the displayed ad creative from the surrounding page, preventing DOM inspection or third-party tracking pixel injection.<\/li>\r\n<\/ul>\r\n\r\n\r\n\r\n<h2 class=\"wp-block-heading\">4. Implications for Website Tagging and Analytics Architecture<\/h2>\r\n\r\n\r\n\r\n<p class=\"wp-block-paragraph\">Adapting website tagging to the post-cookie era requires significant adjustments to tag management implementations:<\/p>\r\n\r\n\r\n\r\n<ul class=\"wp-block-list\">\r\n<li><strong>First-Party Data Prioritization:<\/strong> Tagging infrastructures must focus on robust first-party context collection and server-to-server data flows (e.g., via Server-Side Google Tag Manager) rather than relying on external browser pixels.<\/li>\r\n<li><strong>Permissions Policy Headers:<\/strong> Publishers must explicitly control which embedded third-party scripts can invoke Privacy Sandbox APIs by declaring structured HTTP response headers (such as <code>Permissions-Policy: browsing-topics=(self), run-ad-auction=(self)<\/code>).<\/li>\r\n<li><strong>Asynchronous Attribution Reporting:<\/strong> Conversion tracking shifts to the Attribution Reporting API, where measurement reports are encrypted, delayed, and processed through secure Trusted Execution Environments (TEEs) before being delivered to analytics endpoints.<\/li>\r\n<\/ul>\r\n\n\n<div class=\"lw-quellen\">\n<h2>Sources<\/h2>\n<ul>\n<li><a href=\"https:\/\/privacysandbox.google.com\/private-advertising\/topics\" target=\"_blank\" rel=\"noopener noreferrer\">Topics API<\/a><\/li>\n<li><a href=\"https:\/\/privacysandbox.google.com\/private-advertising\/protected-audience\" target=\"_blank\" rel=\"noopener noreferrer\">Protected Audience API<\/a><\/li>\n<\/ul>\n<\/div>","protected":false},"excerpt":{"rendered":"<p>A technical overview of how Google Privacy Sandbox replaces third-party cookies, shifting ad auctions and interest profiling directly into the browser.<\/p>\n","protected":false},"author":1,"featured_media":13998,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[18],"tags":[91276,91279,91386,91285,91516],"class_list":["post-438","post","type-post","status-publish","format-standard","hentry","category-data-privacy","tag-cookies","tag-prywatnosc-danych-pl","tag-marketing-cyfrowy-pl","tag-first-party-data","tag-tracking"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.1 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>The Post-Cookie Era: Inside Topics API and Protected Audience in Google Privacy Sandbox - Lukas Wojcik - Blog<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.lukaswojcik.com\/blog\/en\/data-privacy\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"The Post-Cookie Era: Inside Topics API and Protected Audience in Google Privacy Sandbox - Lukas Wojcik - Blog\" \/>\n<meta property=\"og:description\" content=\"A technical overview of how Google Privacy Sandbox replaces third-party cookies, shifting ad auctions and interest profiling directly into the browser.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.lukaswojcik.com\/blog\/en\/data-privacy\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\/\" \/>\n<meta property=\"og:site_name\" content=\"Lukas Wojcik - Blog\" \/>\n<meta property=\"article:published_time\" content=\"2026-09-10T09:05:52+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.lukaswojcik.com\/blog\/wp-content\/uploads\/2026\/09\/hero-438-post-cookie-era-topics-api-protected-g.png\" \/>\n\t<meta property=\"og:image:width\" content=\"1200\" \/>\n\t<meta property=\"og:image:height\" content=\"630\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/png\" \/>\n<meta name=\"author\" content=\"luky\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"luky\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"3 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/en\\\/data-privacy\\\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/en\\\/data-privacy\\\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\\\/\"},\"author\":{\"name\":\"luky\",\"@id\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/#\\\/schema\\\/person\\\/895f7604f9b6b71aad9bba33af28d0f9\"},\"headline\":\"The Post-Cookie Era: Inside Topics API and Protected Audience in Google Privacy Sandbox\",\"datePublished\":\"2026-09-10T09:05:52+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/en\\\/data-privacy\\\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\\\/\"},\"wordCount\":562,\"commentCount\":0,\"publisher\":{\"@id\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/#\\\/schema\\\/person\\\/895f7604f9b6b71aad9bba33af28d0f9\"},\"image\":{\"@id\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/en\\\/data-privacy\\\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/wp-content\\\/uploads\\\/2026\\\/09\\\/hero-438-post-cookie-era-topics-api-protected-g.png\",\"keywords\":[\"Cookies\",\"Data Privacy\",\"Digital Marketing\",\"First-Party Data\",\"Tracking\"],\"articleSection\":[\"Data Privacy\"],\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/en\\\/data-privacy\\\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\\\/#respond\"]}]},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/en\\\/data-privacy\\\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\\\/\",\"url\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/en\\\/data-privacy\\\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\\\/\",\"name\":\"The Post-Cookie Era: Inside Topics API and Protected Audience in Google Privacy Sandbox - Lukas Wojcik - Blog\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/en\\\/data-privacy\\\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\\\/#primaryimage\"},\"image\":{\"@id\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/en\\\/data-privacy\\\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/wp-content\\\/uploads\\\/2026\\\/09\\\/hero-438-post-cookie-era-topics-api-protected-g.png\",\"datePublished\":\"2026-09-10T09:05:52+00:00\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/en\\\/data-privacy\\\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\\\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/en\\\/data-privacy\\\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\\\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/en\\\/data-privacy\\\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\\\/#primaryimage\",\"url\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/wp-content\\\/uploads\\\/2026\\\/09\\\/hero-438-post-cookie-era-topics-api-protected-g.png\",\"contentUrl\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/wp-content\\\/uploads\\\/2026\\\/09\\\/hero-438-post-cookie-era-topics-api-protected-g.png\",\"width\":1200,\"height\":630,\"caption\":\"The Post-Cookie Era: Inside Topics API and Protected Audience in Google Privacy Sandbox\"},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/en\\\/data-privacy\\\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"The Post-Cookie Era: Inside Topics API and Protected Audience in Google Privacy Sandbox\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/#website\",\"url\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/\",\"name\":\"Lukas Wojcik - Blog\",\"description\":\"\",\"publisher\":{\"@id\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/#\\\/schema\\\/person\\\/895f7604f9b6b71aad9bba33af28d0f9\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":[\"Person\",\"Organization\"],\"@id\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/#\\\/schema\\\/person\\\/895f7604f9b6b71aad9bba33af28d0f9\",\"name\":\"luky\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/wp-content\\\/uploads\\\/2026\\\/07\\\/lw-x2.jpg\",\"url\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/wp-content\\\/uploads\\\/2026\\\/07\\\/lw-x2.jpg\",\"contentUrl\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/wp-content\\\/uploads\\\/2026\\\/07\\\/lw-x2.jpg\",\"width\":424,\"height\":636,\"caption\":\"luky\"},\"logo\":{\"@id\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/wp-content\\\/uploads\\\/2026\\\/07\\\/lw-x2.jpg\"},\"sameAs\":[\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\"],\"url\":\"https:\\\/\\\/www.lukaswojcik.com\\\/blog\\\/author\\\/luky\\\/\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"The Post-Cookie Era: Inside Topics API and Protected Audience in Google Privacy Sandbox - Lukas Wojcik - Blog","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.lukaswojcik.com\/blog\/en\/data-privacy\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\/","og_locale":"en_US","og_type":"article","og_title":"The Post-Cookie Era: Inside Topics API and Protected Audience in Google Privacy Sandbox - Lukas Wojcik - Blog","og_description":"A technical overview of how Google Privacy Sandbox replaces third-party cookies, shifting ad auctions and interest profiling directly into the browser.","og_url":"https:\/\/www.lukaswojcik.com\/blog\/en\/data-privacy\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\/","og_site_name":"Lukas Wojcik - Blog","article_published_time":"2026-09-10T09:05:52+00:00","og_image":[{"width":1200,"height":630,"url":"https:\/\/www.lukaswojcik.com\/blog\/wp-content\/uploads\/2026\/09\/hero-438-post-cookie-era-topics-api-protected-g.png","type":"image\/png"}],"author":"luky","twitter_card":"summary_large_image","twitter_misc":{"Written by":"luky","Est. reading time":"3 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/www.lukaswojcik.com\/blog\/en\/data-privacy\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\/#article","isPartOf":{"@id":"https:\/\/www.lukaswojcik.com\/blog\/en\/data-privacy\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\/"},"author":{"name":"luky","@id":"https:\/\/www.lukaswojcik.com\/blog\/#\/schema\/person\/895f7604f9b6b71aad9bba33af28d0f9"},"headline":"The Post-Cookie Era: Inside Topics API and Protected Audience in Google Privacy Sandbox","datePublished":"2026-09-10T09:05:52+00:00","mainEntityOfPage":{"@id":"https:\/\/www.lukaswojcik.com\/blog\/en\/data-privacy\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\/"},"wordCount":562,"commentCount":0,"publisher":{"@id":"https:\/\/www.lukaswojcik.com\/blog\/#\/schema\/person\/895f7604f9b6b71aad9bba33af28d0f9"},"image":{"@id":"https:\/\/www.lukaswojcik.com\/blog\/en\/data-privacy\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\/#primaryimage"},"thumbnailUrl":"https:\/\/www.lukaswojcik.com\/blog\/wp-content\/uploads\/2026\/09\/hero-438-post-cookie-era-topics-api-protected-g.png","keywords":["Cookies","Data Privacy","Digital Marketing","First-Party Data","Tracking"],"articleSection":["Data Privacy"],"inLanguage":"en-US","potentialAction":[{"@type":"CommentAction","name":"Comment","target":["https:\/\/www.lukaswojcik.com\/blog\/en\/data-privacy\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\/#respond"]}]},{"@type":"WebPage","@id":"https:\/\/www.lukaswojcik.com\/blog\/en\/data-privacy\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\/","url":"https:\/\/www.lukaswojcik.com\/blog\/en\/data-privacy\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\/","name":"The Post-Cookie Era: Inside Topics API and Protected Audience in Google Privacy Sandbox - Lukas Wojcik - Blog","isPartOf":{"@id":"https:\/\/www.lukaswojcik.com\/blog\/#website"},"primaryImageOfPage":{"@id":"https:\/\/www.lukaswojcik.com\/blog\/en\/data-privacy\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\/#primaryimage"},"image":{"@id":"https:\/\/www.lukaswojcik.com\/blog\/en\/data-privacy\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\/#primaryimage"},"thumbnailUrl":"https:\/\/www.lukaswojcik.com\/blog\/wp-content\/uploads\/2026\/09\/hero-438-post-cookie-era-topics-api-protected-g.png","datePublished":"2026-09-10T09:05:52+00:00","breadcrumb":{"@id":"https:\/\/www.lukaswojcik.com\/blog\/en\/data-privacy\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.lukaswojcik.com\/blog\/en\/data-privacy\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\/"]}]},{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.lukaswojcik.com\/blog\/en\/data-privacy\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\/#primaryimage","url":"https:\/\/www.lukaswojcik.com\/blog\/wp-content\/uploads\/2026\/09\/hero-438-post-cookie-era-topics-api-protected-g.png","contentUrl":"https:\/\/www.lukaswojcik.com\/blog\/wp-content\/uploads\/2026\/09\/hero-438-post-cookie-era-topics-api-protected-g.png","width":1200,"height":630,"caption":"The Post-Cookie Era: Inside Topics API and Protected Audience in Google Privacy Sandbox"},{"@type":"BreadcrumbList","@id":"https:\/\/www.lukaswojcik.com\/blog\/en\/data-privacy\/the-post-cookie-era-inside-topics-api-and-protected-audience-in-google\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.lukaswojcik.com\/blog\/"},{"@type":"ListItem","position":2,"name":"The Post-Cookie Era: Inside Topics API and Protected Audience in Google Privacy Sandbox"}]},{"@type":"WebSite","@id":"https:\/\/www.lukaswojcik.com\/blog\/#website","url":"https:\/\/www.lukaswojcik.com\/blog\/","name":"Lukas Wojcik - Blog","description":"","publisher":{"@id":"https:\/\/www.lukaswojcik.com\/blog\/#\/schema\/person\/895f7604f9b6b71aad9bba33af28d0f9"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.lukaswojcik.com\/blog\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":["Person","Organization"],"@id":"https:\/\/www.lukaswojcik.com\/blog\/#\/schema\/person\/895f7604f9b6b71aad9bba33af28d0f9","name":"luky","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.lukaswojcik.com\/blog\/wp-content\/uploads\/2026\/07\/lw-x2.jpg","url":"https:\/\/www.lukaswojcik.com\/blog\/wp-content\/uploads\/2026\/07\/lw-x2.jpg","contentUrl":"https:\/\/www.lukaswojcik.com\/blog\/wp-content\/uploads\/2026\/07\/lw-x2.jpg","width":424,"height":636,"caption":"luky"},"logo":{"@id":"https:\/\/www.lukaswojcik.com\/blog\/wp-content\/uploads\/2026\/07\/lw-x2.jpg"},"sameAs":["https:\/\/www.lukaswojcik.com\/blog"],"url":"https:\/\/www.lukaswojcik.com\/blog\/author\/luky\/"}]}},"_links":{"self":[{"href":"https:\/\/www.lukaswojcik.com\/blog\/wp-json\/wp\/v2\/posts\/438","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.lukaswojcik.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.lukaswojcik.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.lukaswojcik.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.lukaswojcik.com\/blog\/wp-json\/wp\/v2\/comments?post=438"}],"version-history":[{"count":4,"href":"https:\/\/www.lukaswojcik.com\/blog\/wp-json\/wp\/v2\/posts\/438\/revisions"}],"predecessor-version":[{"id":17920,"href":"https:\/\/www.lukaswojcik.com\/blog\/wp-json\/wp\/v2\/posts\/438\/revisions\/17920"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.lukaswojcik.com\/blog\/wp-json\/wp\/v2\/media\/13998"}],"wp:attachment":[{"href":"https:\/\/www.lukaswojcik.com\/blog\/wp-json\/wp\/v2\/media?parent=438"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.lukaswojcik.com\/blog\/wp-json\/wp\/v2\/categories?post=438"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.lukaswojcik.com\/blog\/wp-json\/wp\/v2\/tags?post=438"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}