Unpacking The Google Content Warehouse API Leak [Evidence-based Insights for SEOs]

The SEO world just got a major wake-up call.

A massive leak of internal Google documentation, dubbed the “Content Warehouse API,” has sent shockwaves through the industry.

This trove of over 2,500 pages provides an unprecedented glimpse into the complex machinery that drives Google Search.

Before we dive in, a crucial disclaimer: The leaked documents are function references, NOT the actual source code of Google's algorithms. While they offer fascinating clues, we can't definitively confirm which signals are actively used in ranking, their relative weights, or how they interact. The insights presented in this blog post are my interpretations and opinions based on the available information, not confirmed facts. Treat them as potential areas of focus, not absolute truths.

That said, the leak offers valuable context and helps us connect the dots between Google's stated best practices, what the SEO industry believes, and the underlying systems that might be enforcing them.

It's a rare opportunity to peer into the black box of search, as even speculative insights can spark valuable SEO experiments.

With that in mind, let's explore the Content Warehouse API leak and what it might mean for SEOs.

Important: Throughout the blog, you'll see references to 'Context from' - these indicate the specific API documentation modules and attributes used to derive the accompanying insights.

Google Systems Breakdown

The leaked documents reveal a fascinating network of interconnected systems that seem to work to power Google Search.

Some of these systems were previously known, and others are news to the community. That said, these systems are responsible for everything from discovering new pages to understanding their content and deciding how they should rank.

Here’s a closer look at some of the most prominent systems discussed in the documentation:

Trawler (Crawling)

Think of Trawler as Google’s web explorer, constantly venturing out to discover and retrieve new information from the vast expanse of the web. Its core purpose is to ensure that Google’s index is constantly updated and reflects the ever-changing landscape of online content.

Key Responsibilities:

  • Fetching and Analyzing Pages: Trawler retrieves pages from the web, analyzes their content type and encoding, checks for redirects, respects robots.txt directives, and records timestamps for freshness analysis.

    • Context from: TrawlerFetchReplyData, TrawlerFetchStatus, TrawlerFetchReplyDataRedirects, TrawlerFetchReplyDataCrawlDates, TrawlerCrawlTimes, TrawlerFetchBodyData
  • Managing Crawl Efficiency: Trawler uses caching to avoid redundant fetches and employs throttling mechanisms to regulate its crawl rate and prevent overloading web servers.

    • Context from: TrawlerFetchReplyData.ThrottleClient, TrawlerHostBucketData, TrawlerHostBucketDataUrlList
  • Ensuring Security: Trawler validates SSL certificates for HTTPS pages to ensure a secure connection and protect user data.

    • Context from: TrawlerSSLCertificateInfo, IndexingBadSSLCertificate
  • Logging Crawl Details: Trawler records detailed information about each crawl, including network data, timestamps, client information, and any policy labels applied to pages (e.g., "spam," "roboted"). This information is used for debugging, performance analysis, and spam detection.

    • Context from: TrawlerTCPIPInfo, TrawlerFetchReplyData, TrawlerClientInfo, TrawlerClientServiceInfo, LogsProtoIndexingCrawlerIdCrawlerIdProto, TrawlerPolicyData, CompositeDocIndexingInfo.urlHistory, CompositeDocIndexingInfo.urlChangerate

Learn more about Google's Trawler system

Alexandria (Indexing)

Once Trawler has completed its exploration, Alexandria (Google’s indexer) steps in to organize and analyze the wealth of discovered information. Think of Alexandria as Google’s grand library, where pages are carefully processed, categorized, and stored in a way that makes them easily searchable.

Key Responsibilities:

  • Data Management and Versioning: Alexandria extracts and stores key document (page) properties (language, title, content length) and manages different versions of data to ensure that Google Search utilizes the most current information.

    • Context from: IndexingDocjoinerDataVersion, DocProperties
  • Content Analysis: Alexandria analyzes anchor text from incoming links, manages alternate URLs for different languages and regions, extracts and analyzes dates within content to determine freshness and timeliness, and reviews numerous other factors.

    • Context from: IndexingDocjoinerAnchorStatistics, IndexingDocjoinerAnchorTrustedInfo, IndexingDocjoinerAnchorSpamInfo, IndexingConverterLocalizedAlternateName, QualityTimebasedSyntacticDate, QualityTimebasedDateUnreliability, QualityTimebasedLastSignificantUpdate,
  • Content Preservation: Alexandria can preserve previously indexed content even if a page is temporarily unavailable or returns an error, preventing valuable information from disappearing from search results.

    • Context from: CompositeDocIndexingInfo.contentProtected
  • Quality Signal Compression: To save space and improve efficiency, Alexandria compresses and stores various page quality signals. These signals are later used by Mustang to evaluate a page’s ranking potential.

    • Context from: CompressedQualitySignals

Learn more about Google's Alexandria system

Mustang (Ranking)

Mustang is the heart of Google’s ranking system. This sophisticated system takes the vast amounts of information gathered and organized by Alexandria and uses it to determine the relevance and authority of pages for specific search queries.

Key Responsibilities:

  • Analyzing Content Signals: Mustang considers a vast array of signals, including spam scores, content freshness, language, mobile-friendliness, topical authority, PageRank, user engagement data (click-through rates), and numerous other factors.

    • Context from: PerDocData, CompressedQualitySignals, QualityNsrNsrData, CompositeDocQualitySignals
  • Generating Search Snippets: Mustang is responsible for creating the snippets that appear in search results, including selecting titles, extracting relevant text passages, and highlighting query terms.

    • Context from: WWWSnippetResponse, QualityPreviewRanklabSnippet, QualityPreviewRanklabTitle
  • Understanding Semantic Meaning: Mustang utilizes machine learning models (RankEmbed) to analyze the meaning and relationships within content and queries, enabling Google to match search intent to relevant pages more effectively.

    • Context from: QualityRankembedMustangMustangRankEmbedInfo

Learn more about Google's Mustang system

SuperRoot (Query Processing)

SuperRoot is the quarterback of Google Search, calling the plays and directing the flow of information to get the best results. It takes user queries as input, then guides them through a sophisticated process of refinement, filtering, blending, and personalization to deliver the most relevant and satisfying results.

Key Responsibilities:

  • Query Interpretation and Refinement: SuperRoot analyzes user queries, clarifies intent, rewrites complex queries, and blends results from different search verticals (images, videos, news, etc.) to create a comprehensive and personalized search experience.

    • Context from: QualityGenieComplexQueriesComplexQueriesOutputRewrite, MustangReposWwwSnippetsSnippetsRanklabFeatures, QualityRichsnippetsAppsProtosLaunchableAppPerDocData, Sitemap, QualitySitemapTarget, QualitySitemapTargetGroup, WWWSnippetResponse, ImageRepositoryVideoProperties
  • Snippet Optimization: SuperRoot may leverage Snippet Brain, a machine learning system, to enhance the quality and relevance of search snippets, potentially overriding default selections.

    • Context from: MustangReposWwwSnippetsSnippetsRanklabFeatures

Learn more about Google's SuperRoot system

Navboost acts as Google’s user behavior analyst, continuously studying users experiences based on Chrome clicksteam data in order to refine and improve its ranking algorithms and the effectiveness of search results.

Key Responsibilities:

  • Clickstream Analysis: Navboost collects and analyzes clickstream data, including clicks, impressions, dwell times, and bounce rates, to understand user preferences and the effectiveness of search results.

    • Context from: QualityNavboostCrapsCrapsData, QualityNavboostCrapsAgingData, QualityNavboostCrapsCrapsDevice
  • Scoring and Signal Integration: Navboost assigns scores to pages and websites based on user engagement data, integrating these signals into various parts of the search ecosystem, including ranking, sitemap generation, and potentially snippet selection.

More Details - Key Signals:

  • Click and Impression Data: Navboost collects a wealth of data about user clicks and impressions. It aggregates this data by country, language, user device, and various other factors, creating a detailed picture of how users engage with different pages and search features.

    • Context from: qualitynavboostcrapscrapsdata
  • Navboost Scores: Based on engagement data, Navboost assigns scores to pages and websites, reflecting click popularity and user satisfaction. These scores seem to influence several Google Search systems such as search ranking and the selection of featured snippets.

    • Context from: QualityNavboostCrapsCrapsData, QualityNavboostCrapsCrapsPatternSignal
  • Craps Click Signals: Navboost goes beyond just counting clicks. It analyzes the quality of clicks to understand whether users found the content valuable.

    • Good Clicks: A good click suggests that a user found the linked page relevant and helpful, spending a reasonable amount of time engaging with the content.

    • Bad Clicks: A bad click typically involves a user quickly returning to the search results (a “bounce”), indicating that the page did not meet their expectations or needs.

    • Last Longest Clicks: Measures the duration of a user’s visit to a page, especially if it was the last page in a search session. Longer dwell times often indicate higher content quality and user satisfaction.

    • Context from: QualityNavboostCrapsCrapsClickSignals

  • Absolute Impressions: Navboost tracks the total count of page views in search results, providing a baseline measure of visibility.

    • Context from: QualityNavboostCrapsCrapsClickSignals.absoluteImpressions
  • Unicorn Clicks: To gain insights into specific user segments or niche behaviors, Navboost identifies clicks from a distinct group of users called “Unicorns.” This could involve users who frequently engage with a particular topic or exhibit unique search patterns.

Learn more about Google's Navboost system

Other Systems

In addition to the primary systems, the Content Warehouse API leak reveals a number of other components and algorithms that play significant roles in how Google assesses and ranks web pages.

Here’s details on select supporting systems and the data points they seem to leverage:

  • Volt: Responsible for evaluating mobile-friendliness, Core Web Vitals (page speed, responsiveness, visual stability), HTTPS security, and interstitial compliance to enhance mobile search rankings and user experience.

    • Context from: IndexingMobileVoltVoltPerDocData, IndexingMobileVoltCoreWebVitals, SmartphonePerDocData, MobilePerDocData, IndexingMobileSpeedPageSpeedFieldData.
  • SpamBrain: Google's AI-powered spam detection system identifies spam by analyzing link networks, content quality, historical spam flags, anchor text, and user engagement at both the site and document (page) levels.

    • Context from: PerDocData.spambrainData, PerDocData.spambrainTotalDocSpamScore, SpamBrainPageClassifierAnnotation.
  • Firefly: Responsible for delivering trustworthy content by analyzing content quality, author expertise, and link authority to ensure high-quality, reliable information.

    • Context from: PerDocData.fireflySiteSignal, QualityCopiaFireflySiteSignal, QualityCopiaFireflySiteInfo.
  • Dups/URL Forwarding System: The system responsible for managing duplicate content and URL redirects, ensuring the correct (canonical) version of a page is indexed and consolidated with all relevant signals.

    • Context from: CompositeDocForwardingDup, TrawlerFetchReplyDataRedirects, IndexingConverterRedirectChain, IndexingConverterRedirectParams.
  • Other Content Models (Chard, Tofu, Keto, BabyPanda): These models use various algorithms and signals to assess content quality, trustworthiness, and user experience at both the document (page) and site level.

    • Context from: qualityNsrPqData.chard, qualityNsrPqData.tofu, qualityNsrPqData.keto, CompressedQualitySignals.babyPandaDemotion.

Insights Based on Leaked Document Attributes

The leaked “Content Warehouse API” documentation provides a treasure trove of information for SEOs. While these documents are function references, not source code, they reveal a vast array of attributes and signals that Google may be using to evaluate web pages. By understanding these potential ranking factors, SEOs can refine their strategies and optimize content for better visibility and performance.

Here’s a breakdown of select noteworthy attributes, grouped by SEO focus area, along with the specific modules or fields referenced in the documentation:

Content Length and Structure

Google analyzes various aspects of content length and structure to assess readability, understand topical focus, and determine relevance to user queries.

Key Attributes & Supporting Evidence:

  • Word-to-Token Ratio: This ratio provides insights into content density and writing style. A higher word-to-token ratio may suggest that content is more concise, uses more meaningful words, and avoids unnecessary filler.

    • Example: A page with 100 words and 150 tokens (including punctuation) has a word-to-token ratio of 0.67. A page with 100 words and 120 tokens has a ratio of 0.83, indicating a higher density of meaningful words.

    • Context from: PerDocData.bodyWordsToTokensRatioBegin, PerDocData.bodyWordsToTokensRatioTotal

  • Hard Token Count in Titles: Google emphasizes meaningful words (hard tokens) in titles to discourage keyword stuffing. Titles with a strong focus on relevant hard tokens are more likely to accurately reflect the page's content.

    • Example: Let's say you have the title: "The Best Chocolate Chip Cookie Recipe Ever."

      • Stop Words: "The," "and," "Ever"

      • Hard Tokens: "Best," "Chocolate," "Chip," "Cookie," "Recipe"

    • Context from: PerDocData.titleHardTokenCountWithoutStopwords, PerDocData.originalTitleHardTokenCount

  • Average Weighted Font Size: Google is likely paying close attention to visual cues, including font sizes. The average weighted font size of terms in a document (page) could provide insights into the visual hierarchy and emphasis within the content, helping Google identify the most prominent and important information.

    • Example: Key terms like "pizza" and "history" might be displayed in a larger font size (or as bolded text) than less important words, signaling their relevance and prominence.

    • Context from: DocProperties.avgTermWeight

  • Page Regions: Clearly defined page regions, created using semantic HTML5 tags and headings, make it easier for Google to understand the structure of a page and identify relevant sections for featured snippets or other rich results.

    • Example: A well-structured blog post might have distinct page regions for the introduction, each main point, and a conclusion, all clearly marked with headings (<h1>, <h2>, etc.).

    • Context from: PerDocData.pageregions

  • Boilerplate Content: Excessive boilerplate content - repetitive or unoriginal text - can detract from user experience and dilute the value of a page's unique information. Google likely penalizes pages with high boilerplate ratios, favoring content that is original and user-focused.

    • Context from: QualityPreviewRanklabSnippet.hasSiteInfo, QualityPreviewRanklabTitle.goldmineHasBoilerplateInTitle
  • On-Page Table of Contents Usage: A well-structured table of contents can enhance navigation and make it easier for users and Google to find specific information within a page. Google often uses table of contents entries to generate direct links to sections within a page.

    • Context from: WWWSnippetResponse.sectionHeadingAnchorName, WWWSnippetResponse.sectionHeadingText
  • Number of Punctuations: While it might seem surprising, Google even analyzes punctuation. This could be a signal of grammatical correctness, writing quality, and overall content polish.

    • Context from: DocProperties.numPunctuations
  • Leading Text: The leadingtext field in the documentation is how Google identifies and extracts introductory text that is highly relevant to a page's main topic in orde to to use within search snippets (i.e., what’s used in SERPs rather than website-defined meta descriptions).

    • Context from: DocProperties.leadingtext

Content Relevancy and Quality

Google’s ultimate goal is to connect users with the most relevant and highest quality content. It uses a variety of sophisticated techniques to assess content and ensure it aligns with search intent.

Key Attributes & Supporting Evidence:

  • Salient Terms: Google performs deep analysis of term importance and relevance to understand the core topics of a document (page) and its suitability for specific search queries. The salientTerm.salience field likely indicates the weight or significance of a term in describing the pages subject matter.

    • Example: In an article analyzing the "Impact of Analytics on SEO," terms like "SEO," "analytics," "keywords," "search engine rankings," and "data-driven decisions" would likely have high salience scores.

    • Context from: qualitySalientTermsSalientTermSet

  • Site Focus Scores: Google looks at a website as a whole to understand relevance. There is a siteFocusScore attribute, which seems to represent how closely a website's content aligns with a specific topic or niche using content embeddings (vectorized/numerical representations of content).

    • Example: A higher site focus score might indicate that a website has a clear topical focus and covers its subject matter in depth.

    • Context from: QualityAuthorityTopicEmbeddingsVersionedItem.siteFocusScore

  • Original Content Score: Uniqueness and originality are highly valued by Google. The OriginalContentScore from Google’s documentation likely measures the originality of a page's text, penalizing pages that are copied or scraped from other sources and rewarding pages with fresh, unique content.

    • Example: A blog post offering a unique statistical analysis of SEO strategies would likely receive a high original content score, whereas a page that merely rehashes common SEO tips from other websites would receive a lower score.

    • Context from: PerDocData.OriginalContentScore

  • Content Attribution Signals: The PerDocData.contentAttributions field hints at Google's growing ability to identify the original source of content and track how it has been reused across the web. This could be used to combat plagiarism, prioritize original reporting, and give greater visibility to authoritative content creators.

    • Example: If a website reposts an SEO expert's article without permission or attribution, Google might be able to identify the original source and prioritize it in search results.

    • Context from: PerDocData.contentAttributions

  • Authenticity Signals: The IndexingDocjoinerDataVersion.predictedAuthenticity field suggests that Google is developing ways to automatically assess the authenticity and trustworthiness of content. This might involve analyzing writing style, source reputation, and potential fact-checking signals to filter out misleading or unreliable information.

    • Example: A website known for spreading rumors and false information might be flagged as having low authenticity, thus immediately negatively impacting a pages ability to rank.

    • Context from: IndexingDocjoinerDataVersion.predictedAuthenticity

  • Featured Image Properties: Google evaluates images associated with a page, not just for their visual appeal, but also for their relevance to the content and their potential to inspire users. The inspiration_score field suggests that visually engaging images might receive a boost in some search scenarios.

    • Example: A striking image of a website achieving a top ranking on Google would likely have a high inspiration score for an SEO success story blog.

    • Context from: imagedata.featuredImageProp

Content Freshness

Timeliness is a crucial factor in search relevance, especially for topics where new information emerges frequently. Google uses various signals to determine the age and freshness of web content.

Key Attributes & Supporting Evidence:

  • Content Freshness Signals: The documentation reveals a number of attributes related to content freshness. These signals likely help Google assess the age and timeliness of content, influencing how prominently a page is featured in search results.

    • Publication Date: Google analyzes dates mentioned within the content, including dates marked up with structured data, to understand when the content was originally published or when specific events or updates occurred.

    • Last Update Date: Google identifies signals that indicate when a page was last significantly updated, such as changes to text, image additions, or other content modifications.

    • Frequency of Updates: Google seems to track how often a page is updated. Pages with frequent, meaningful updates may receive a freshness boost.

    • Domain and Host Age: The age of a website and the specific host can be signals of authority. Older, well-established websites often have a stronger reputation and a larger base of backlinks.

  • Context from: PerDocData.semanticDateInfo, PerDocData.semanticDate, PerDocData.datesInfo, PerDocData.lastSignificantUpdate, PerDocData.freshnessEncodedSignals, PerDocData.freshboxArticleScores, PerDocData.domainAge, PerDocData.hostAge

Entity Mentions in Content

The leaked documentation reveals that Google goes beyond simply identifying entities; it meticulously analyzes how those entities are mentioned within a page's content, anchor text, and surrounding context.

Key Attributes & Supporting Evidence:

  • Mention Context: Google analyzes the textual neighborhood of an entity mention to clarify its meaning and determine its relevance to the overall topic.

    • Example: A mention of "Apple" could refer to the fruit, the company, or a person's name. The surrounding text helps Google understand which meaning is intended.

    • Context from: RepositoryWebrefNgramContext, RepositoryWebrefNgramMention

  • Mention Types and Prominence: Google recognizes that not all mentions are created equal. Mentions in prominent locations (titles, headings, anchor text) carry more weight than mentions within body text.

    • Example: A mention of "SEO" in the title of a page is a stronger signal of topical relevance than a mention of "SEO" in the footer.

    • Context from: RepositoryWebrefEntityAnnotations.topicalityScore, Anchors.Anchor, QualitySalientTermsSalientTerm.signalTerm

  • Mention Confidence: Google assigns confidence scores to entity mentions, reflecting the certainty that a specific phrase truly refers to a particular entity.

    • Context from: RepositoryWebrefEntityAnnotations.confidenceScore, RepositoryWebrefMention.confidenceScore
  • Implicit Mentions: Google can infer entity associations even when an entity is not directly named.

    • Example: A page about "digital marketing strategies" might be implicitly related to "SEO" or "social media marketing" even without explicitly using those terms.

    • Context from: RepositoryWebrefEntityAnnotations.isImplicit, RepositoryWebrefMention.isImplicit

  • Co-occurrence of Mentions: The presence of multiple related entity mentions strengthens Google's understanding of a page's topic.

    • Example: A page mentioning "Elon Musk," "SpaceX," and "Tesla" clearly indicates a focus on Elon Musk and his companies.

    • Context from: RepositoryWebrefWebrefEntities, RepositoryWebrefEntityJoin

Authority and Trust

Beyond content, Google assesses the authority and trustworthiness of websites and individual pages. These signals help determine which sources are most credible and deserving of top rankings.

Key Attributes & Supporting Evidence:

  • PageRank: Still seems to be a core measure of website/page importance. PageRank leverages link analysis to gauge a site's authority.

    • Context from: PerDocData.pagerank0, PerDocData.pagerank1, PerDocData.pagerank2, PerDocData.toolbarPagerank, PerDocData.homepagePagerankNs, research_science_search_source_url_docjoin_info.pagerank
  • Topical Authority and Relevance: Google uses various signals to determine how authoritative a document (page) is within its specific topic. This likely involves analyzing the website's overall reputation, the author's expertise (if known), and the depth and accuracy of the content itself.

    • Example: A website run by a team of experienced SEO professionals, featuring in-depth articles on SEO strategies, techniques, and trends, would be considered highly authoritative on SEO-related topics.

    • Context from: PerDocData.fireflySiteSignal, PerDocData.productSitesInfo, PerDocData.hostNsr, PerDocData.nsrDataProto

  • Site Authority: Google seems to use a “siteAuthority” metric. A higher Site Authority score suggests that Google views the website as a reliable and reputable source of information. This score likely considers a range of factors, including content quality, backlink profile, user engagement signals, and brand reputation.

    • Context from: CompressedQualitySignals.siteAuthority
  • Tundra Clustering: Seems to be a system Google uses to group websites that are topically similar or related to each other at a site-level. It's like creating "neighborhoods" of websites within a particular niche or industry.

    • How it might work: Google could be analyzing various factors to cluster sites, such as:

      • Link relationships: Sites that frequently link to each other or share a similar set of backlinks.

      • Content analysis: Sites that use similar vocabulary, cover related topics, or have a comparable content structure.

      • User behavior: Sites that users tend to visit together or find through similar search queries.

    • Why it matters for SEO: Being clustered with other authoritative sites in your niche can potentially boost your website's topical authority. It suggests to Google that your site is part of a trusted network of sources on a particular topic.

    • Context from: PerDocData.tundraClusterId

  • Official Pages: Are websites or pages that Google deems to be the most authoritative and trustworthy sources of information for a specific entity.

    • How they are identified: Google likely uses a combination of signals to determine official pages, including:

      • Explicit claims: Websites might claim to be the official source for an entity through structured data or clear statements on their website.

      • Link analysis: Official websites often receive a high volume of backlinks from other reputable sources, particularly within their specific industry or niche.

      • User behavior: Users are more likely to search for and visit official websites when looking for information about a particular entity.

    • Why it matters for SEO: Official pages often receive preferential treatment in search results. They are more likely to appear in knowledge panels, featured snippets, and top organic rankings for queries related to their entity.

    • Context from: PerDocData.queriesForWhichOfficial

  • Authority in Research and Academia: Google prioritizes authority signals from academic sources and research databases, suggesting that links and citations from these trusted sources carry significant weight.

    • Context from: research_science_search_source_url_docjoin_info.scholarInfo, research_science_search_source_url_docjoin_info.petacatInfo

Anchor text—the clickable words used in a hyperlink—continues to be a powerful signal for Google, offering valuable clues about the relevance and authority of web pages. The Content Warehouse API leak reveals the depth of analysis Google applies to anchor text, emphasizing both its importance and the need for SEOs to avoid manipulative practices.

Key Attributes & Supporting Evidence:

  • Penguin Algorithm: Google's Penguin algorithm is seemingly still in use - targeting websites with manipulative or spammy link profiles. Sites penalized by Penguin may experience significant ranking drops.

    • Context from: IndexingDocjoinerAnchorStatistics.penguinPenalty, IndexingDocjoinerAnchorStatistics.penguinLastUpdate, IndexingDocjoinerAnchorStatistics.penguinEarlyAnchorProtected, IndexingDocjoinerAnchorStatistics.penguinTooManySources
  • Anchor Text Diversity and Distribution: Google favors a natural and diverse anchor text profile, with variations in wording and links from various domains.

    • Context from: IndexingDocjoinerAnchorStatistics.anchorPhraseCount, IndexingDocjoinerAnchorStatistics.totalDomainPhrasePairsSeenApprox, IndexingDocjoinerAnchorStatistics.totalDomainsAbovePhraseCap
  • Anchor Text Context and Surrounding Text: Google analyzes the text surrounding a link, not just the anchor text itself, to better understand the context and intent of the link.

    • Context From: Anchors.Anchor.fullLeftContext, Anchors.Anchor.fullRightContext, Anchors.Anchor.context, Anchors.Anchor.context2
  • Anchor Text Relevance to Landing Page: Google assesses the relevance of anchor text to the content of the landing page (the page being linked to).

    • Context From: IndexingDocjoinerAnchorStatistics.pageMismatchTaggedAnchors, QualitySalientTermsSalientTermSet
  • Anchor Text from Homepages: Links and anchor text from website homepages are likely given special consideration. A homepage is often seen as the most authoritative page on a site, so links from homepages may carry more weight.

    • Context From: Anchors.AnchorSource.homePageInfo, IndexingDocjoinerAnchorStatistics.minHostHomePageLocalOutdegree, IndexingDocjoinerAnchorStatistics.minDomainHomePageLocalOutdegree
  • Anchor Text Age and History: The age of a link and its anchor text can be a factor in Google's evaluation. However, the documentation didn’t specify how this is being used. It’s possible that anchors (links) that have existed for a longer period are often seen as more trustworthy, while sudden spikes in new links with specific anchor text might be a sign of manipulation.

    • Context From: Anchors.Anchor.creationDate, Anchors.Anchor.firstseenDate, IndexingDocjoinerAnchorStatistics.linkBeforeSitechangeTaggedAnchors, IndexingDocjoinerAnchorStatistics.timestamp

Indexing and Crawl Signals

Google’s ability to crawl and index websites efficiently and accurately is fundamental to its success. The leaked documents provide insights into this critical process.

Key Attributes & Supporting Evidence:

  • URL Canonicalization and Duplication: Google's systems are designed to identify and handle duplicate content, ensuring that only the most authoritative version of a page is indexed.

    • Example: If an e-commerce site has multiple URLs for the same product (e.g., with and without tracking parameters), Google will choose a canonical URL and consolidate signals to it, avoiding duplicate content issues and focusing SEO efforts on a single URL.

    • Context from: CompositeDocForwardingDup, IndexingDupsLocalizedLocalizedCluster

  • Crawl Status and Robots Instructions: Google uses a variety of signals to understand how it should crawl and index a website. These signals include items such as:

    • Crawl Status: This indicates whether a page was successfully crawled, encountered an error, or was blocked by robots directives.

    • Robots.txt Handling: Google respects the instructions in a site's robots.txt file, which can specify which pages or directories are allowed or disallowed for crawling.

    • Context from: CompositeDocIndexingInfo.crawlStatus, CompositeDocIndexingInfo.convertToRobotedReason, IndexingConverterRobotsInfo

  • Changerate Information: Google tracks how frequently a page's content changes to determine how often it should be recrawled.

    • Example: A site with live scores will be crawled more frequently than one with static information about sports history.

    • Context from: CompositeDocIndexingInfo.urlChangerate, CompositeDocIndexingInfo.urlHistory

Specified “Demotions”

The leaked Content Warehouse API documents highlight various demotion mechanisms that Google employs to lower the ranking of pages that violate its quality guidelines or exhibit spammy characteristics. Understanding these demotion signals can be important for SEOs to ensure their websites avoid penalties and maintain a strong search presence.

Key Attributes & Supporting Evidence:

  • Panda Demotion: Targets low-quality pages, often characterized by thin content, duplicate content, excessive advertising, user-generated spam, and other factors that negatively impact user experience.

    • Context from: CompressedQualitySignals.pandaDemotion
  • Baby Panda Demotion: Seems to be a refinement or extension of the original Panda algorithm, potentially focusing on newer forms of low-quality content or specific website characteristics that warrant demotion.

    • Context from: CompressedQualitySignals.babyPandaDemotion, CompressedQualitySignals.babyPandaV2Demotion
  • Nav Demotion: Limited information in docs. This likely targets pages or websites that have poor site structure, broken links, confusing redirects, or other factors that hinder user navigation and create a negative browsing experience.

    • Context from: CompressedQualitySignals.navDemotion
  • Exact Match Domain Demotion: Penalizes websites that rely too heavily on exact match domains (EMDs) - domain names that exactly match a target keyword phrase. This demotion is designed to prevent low-quality websites from gaining an unfair ranking advantage solely based on their domain name.

    • Context from: CompressedQualitySignals.exactMatchDomainDemotion
  • Anchor Mismatch Demotion: Targets pages where the anchor text of incoming links does not accurately reflect the content of the page. This could indicate attempts to manipulate rankings through keyword-rich anchor text that is unrelated to the actual content.

    • Context from: CompressedQualitySignals.anchorMismatchDemotion
  • SERP Demotion: A more general demotion applied to pages that perform poorly in search results, based on aggregate user behavior and feedback. This could include pages with high bounce rates, low dwell times, or negative user interactions (e.g., "pogo-sticking," where users quickly return to the search results).

    • Context from: CompressedQualitySignals.serpDemotion
  • Product Review Demotions: Specifically designed for product review websites and pages, these demotions target low-quality reviews or sites with thin content, lack of expertise, or other factors that diminish the value and trustworthiness of product reviews.

    • Context from: CompressedQualitySignals.productReviewPDemoteSite, CompressedQualitySignals.productReviewPDemotePage

What SEOs Should Be Doing?

The leaked documentation offers a goldmine of insights into Google's search systems, providing a rare glimpse into the factors that influence rankings. SEOs should be leveraging these insights to refine their strategies and stay ahead of the curve.

1. Double Down on Core SEO Best Practices

The leaked documents reinforce the importance of fundamental SEO principles. Google is getting even more sophisticated at evaluating content quality, relevance, authority, technical, and user engagement signals.

Here are some fundamental tactics that are supported by the Google Leak:

Content/On-Page:

  • Prioritize Quality and Originality:

    • Go Beyond Simple Keyword Targeting: Create in-depth, comprehensive content that truly satisfies user needs. This means focusing on E-E-A-T (Experience, Expertise, Authoritativeness, Trustworthiness), especially for YMYL (Your Money or Your Life) topics.

    • Think like a publisher: Invest in creating high-quality, original content that people will want to read, share, and link to.

    • Demonstrate Expertise: Showcase your knowledge and experience through well-researched, insightful, and data-driven content.

    • Focus on User Intent: Understand the search queries that bring users to your pages and tailor your content to directly address their needs and questions.

    • Provide Clear and Actionable Information: Make it easy for users to find the information they need and take action (if applicable). Use clear language, concise instructions, and relevant visuals.

  • Demonstrate Authenticity:

    • Transparent Contact Information: Ensure your website has clear and accessible contact information (address, phone number, email) to build trust and legitimacy.

    • About Us Page: Create a comprehensive “About Us” page that details your company’s mission, values, team, and expertise.

    • Author Bios: For content with bylines, include author biographies that showcase their credentials, experience, and relevant links.

    • Fact-Checking and Verification: Clearly indicate how you fact-check your content and cite reputable sources to support your claims.

  • Content Structure and Readability:

    • Structure for Humans (and Bots): Well-structured content is easier for both users and Google to understand. Use clear headings, subheadings, bullet points, concise paragraphs, and descriptive anchor text to help Google identify salient terms, extract relevant passages for snippets, and understand the overall topic and flow of your content.
  • Content Freshness and Timeliness:

    • Leverage Semantic Date Information: Use clear and consistent date formatting within your content. Leverage structured data (e.g., Article schema) to provide explicit publication and modification dates. Keep content updated regularly, especially for time-sensitive topics.

    • Address Unreliable Date Signals: Ensure that dates mentioned in your content are accurate and consistent with the surrounding context.

  • Content Attribution and Authority:

    • Attribute Sources Meticulously: Citing sources and avoiding plagiarism isn’t just ethical, it’s likely a ranking factor based on the documentation. Google seems to be actively working on identifying original content and how it’s reused.

    • Incorporate On-Page Optimization Insights:

      • Optimize for Passage Ranking: Structure your content with clear subheadings and address specific questions or subtopics concisely within a page.

      • Understand Visual Weight: Pay attention to the visual hierarchy and font sizes of key terms in your content. Prominently displaying important information might signal relevance to Google.

  • Optimize for Entity Mentions:

    • Optimize for Relevant and Contextual Mentions: When you mention entities, make sure they relate to your page's topic and use them in a way that provides clear context to Google.

    • Prioritize Entity Prominence: Feature key entities in your titles, headings, and anchor text.

    • Use Clear and Unambiguous Language: Use specific entity names and terms that Google can easily identify. Avoid vague or overly general language.

  • Avoid Low-Quality Content Traps:

    • Combat "Video LQ" Demotion: If your site features video content, be mindful of signals that might classify it as low-quality. Ensure your videos are relevant, engaging, and hosted on a reputable platform or well-optimized video player.

    • Address Page2Vec "LQ" Signals: Page2Vec is a machine learning model that analyzes content to identify low-quality pages. Focus on creating comprehensive, informative content that avoids thin content or signs of automation.

Technical SEO:

  • URL Management:

    • Canonicalization is Critical: Make sure Google indexes the right version of your pages by using canonical tags.

    • Redirects Need to be Spot On: Use permanent (301) redirects for moved content and temporary (302) redirects when appropriate. Avoid redirect chains and loops.

  • Crawl and Index Control:

    • Robots.txt Needs Constant Attention: Double-check that your robots.txt file isn’t blocking Google from accessing essential pages.

    • Monitor Crawl Errors: Regularly review Google Search Console for crawl errors and indexing issues.

    • Optimize for Crawl Budget:

      • Submit an XML sitemap to Google Search Console.

      • Use robots.txt to block unnecessary or low-value pages from being crawled.

      • Fix broken links and redirect chains to prevent wasted crawl budget.

  • Site Structure and Navigation:

    • Prioritize Internal Linking:

      • Use a logical internal linking structure that helps users and Google navigate your site.

      • Employ relevant anchor text that accurately describes the linked content.

      • Link to important pages from multiple relevant pages on your site.

  • Internationalization and Localization:

    • Use separate URLs with dedicated language subdirectories for translated content.

    • Go beyond simple translation and adapt content to match local cultural nuances and preferences.

  • JavaScript SEO:

    • Ensure your JavaScript content is rendered and accessible to Google.

    • Test your site using Google’s Mobile-Friendly Test, Rich Results Test, and Google Search Console’s URL Inspection to identify rendering issues.

    • Consider dynamic rendering or server-side rendering if needed.

  • Structured Data for Indexability:

    • Go Beyond Rich Snippets: Think of Schema.org structured data as more than just a tool for rich results. It helps the Alexandria system understand your content’s structure and meaning, potentially influencing how your pages are categorized and indexed.

    • Choose Relevant Schema Types: Carefully select schema types that accurately represent your content (Article, Product, Recipe, Event, etc.) to provide clear signals to Google.

    • Keep Schema Up-to-Date: Google is constantly adding support for new schema properties and types. Stay informed about the latest updates and experiment with new implementations to enhance your content’s visibility.

Off-Page SEO:

  • Link Building:

    • Earn Links from Trusted Sources: Per the SEO 101 tips we all know and love, focus on building high-quality content that naturally attracts links from authoritative websites in your niche.

    • Develop a Natural Link Profile: Avoid any link-building tactics that appear manipulative or artificial. Aim for a diverse mix of links from various sources (editorial links, resource pages, guest posts, etc.).

    • Craft Natural and Relevant Surrounding Text: Write clear, informative text around your links, naturally incorporating relevant keywords and phrases that provide context for the linked page.

    • Diversify Your Link Profile Beyond Backlinks: Google's advanced link analysis likely extends beyond traditional backlinks. Explore opportunities to earn mentions and brand associations on authoritative websites.

  • Reputation and Authority:

    • Build Topical Authority in Niche Communities: Actively participate in relevant online communities, forums, and industry publications. Share valuable insights, answer questions, and contribute to discussions to build a reputation as a knowledgeable authority within your niche.

    • Leverage Local SEO Signals (If Applicable): If you have a local business, ensure your business information (NAP) is consistent across online directories (citations). Also, optimize your Google My Business profile and encourage customer reviews.

User Experience (UX):

  • Mobile Optimization:

    • Mobile-First is the Default: Design and optimize your site with a mobile-first approach, as Google predominantly crawls and indexes the mobile version of websites.

    • Understand Mobile Interstitial Policies: Review Google’s guidelines and avoid pop-ups or overlays that block the main content or create a frustrating user experience on mobile devices.

  • Performance and Core Web Vitals:

    • Regularly check the Core Web Vitals report in Google Search Console, focusing on the real-user data (CrUX).

    • Prioritize website improvements based on the metrics that show the greatest need for attention.

  • Holistic UX Considerations:

    • Page Speed Optimization: Aim for fast page loading times across all devices.

    • Mobile Usability: Design for easy navigation, clear typography, and intuitive interactions on mobile.

    • Readability: Use clear and concise language, well-structured content, and appropriate font styles and sizes to enhance readability.

    • Accessibility: Ensure your website is accessible to users with disabilities by following accessibility best practices (WCAG).

2. Formulate Hypotheses for the Future of SEO

The Content Warehouse API leak provides more than just a snapshot of current ranking factors – it offers clues about the direction Google Search is heading.

Here are some hypotheses to consider as you formulate your future SEO strategies:

  • Content Will Be Judged on Nuanced Quality Signals:

    • Fact-Checking and Accuracy: Google's algorithms might be getting significantly better at detecting factual inaccuracies or inconsistencies. Invest in thorough fact-checking, cite reputable sources, and ensure your content aligns with widely accepted knowledge.

    • Sentiment and Tone: While the sentiment snippet module is deprecated, Google likely continues to explore ways to understand sentiment and tone. Strive for a positive and helpful tone, address user concerns empathetically, and avoid overly promotional or controversial language.

    • Readability and Engagement: Readability and engagement metrics are likely becoming more important as Google aims to understand how well users absorb information. Focus on clear, concise writing, well-structured content, and compelling storytelling to keep users engaged.

  • Prepare for a Potential "Source Graph":

    • Google's ability to track content attribution might be a stepping stone to a "Source Graph" - a network that maps the relationships between content creators and how information spreads across the web.

      • Build a Strong Content Reputation: Focus on creating original, high-quality content that others are likely to cite and reference.

      • Link to Authoritative Sources: When citing your sources, prioritize linking to well-respected websites and publications. This can help associate your content with trusted entities.

  • Embrace Entity-First SEO:

    • The Knowledge Graph is becoming increasingly central to how Google understands and organizes information.

      • Structure Content Around Entities: Optimize your content around relevant entities (people, places, things, concepts). Use clear and consistent language to describe entities, and leverage schema.org structured data to connect your content to the Knowledge Graph.

      • Become a Recognized Entity: Aim to become a recognized entity within your niche. Build a strong online presence, earn backlinks from authoritative sources, and encourage mentions and citations.

  • Embrace Emerging Content Formats:

    • Interactive and Immersive Experiences: Google is indexing and understanding interactive content, and likely exploring immersive formats like AR and VR. Explore these technologies to enhance user engagement.

    • Podcasts and Other Audio Content: Google's growing focus on podcasts suggests a future where audio content plays a larger role in search. Optimize your podcasts for discoverability and consider how audio can complement your existing content strategy.

  • Think Beyond Mobile-First to Cross-Device Optimization:

    • As users seamlessly switch between devices (phones, tablets, desktops), Google is likely moving towards a more cross-device understanding of user behavior.

      • Provide a Consistent Experience: Ensure your website offers a seamless and consistent experience across all devices.

      • Analyze Cross-Device Behavior: Use analytics to understand how users interact with your content across different devices and optimize accordingly.

  • Prepare for the Continued Rise of Visual and Multimodal Search:

    • Google is investing heavily in understanding visual content, including images and videos.

      • Optimize Images for Search: Go beyond basic image optimization (alt text, file names) and consider how images can contribute to your overall content strategy.

      • Explore Multimodal Content: Experiment with combining different content formats (text, images, video, audio) to create richer and more engaging experiences.

3. Build Navboost-Inspired Internal Measurement Plan

Navboost is a critical factor in ranking, as referenced in both documentation and DOJ antitrust proceedings. SEOs should develop an internal measurement system aligned with Google's Navboost concepts of "good clicks" and "bad clicks" to analyze user engagement and content effectiveness.

By understanding and emulating how Google might be measuring user satisfaction, you can make data-driven decisions to improve your content and align with Google's quality standards.

Here’s an example of how you can attempt to leverage data to create your own Navboost-like classification system:

Approach Breakdown: Tracking Implementation & Analysis

1: Define System for "Good Click" and “Bad Click” Measurement

  1. Page-Specific Engagement Factors:

    • Scroll Depth: Track scroll depth as a percentage (e.g., 25%, 50%, 75%, 100%) to understand how deeply users are engaging with content.

    • Time on Page: Measure the time users spend on a page, but consider varying thresholds based on content length and type (e.g., longer articles might require a longer minimum time).

    • Internal Clicks: Track clicks on internal links within a page, as this suggests users are exploring related content and engaging further with the website.

    • Bounce Rate: A high bounce rate (users leaving after viewing only one page) can indicate a bad click, but it's important to consider context. A high bounce rate might be normal for certain types of pages.

    • Dwell Time: A very short dwell time (how long a user spends on a page prior to leaving), especially for longer content, often suggests the user didn't find the content engaging or relevant. However, adjust your dwell time thresholds based on content type and length.

    • Conversions (If Applicable): For pages offering downloadable content, forms, and other tracked conversion types, these can be used as a strong engagement signal.

    • Video Engagement (If Applicable): If you have videos embedded on your pages, track video-specific metrics:

      1. Play Rate: The percentage of users who start playing a video.

      2. Average Watch Time: How long, on average, users watch a video.

      3. Completion Rate: The percentage of users who watch a video to the end.

    • Social Shares (If Applicable): Track social sharing actions taken directly from a page. A high number of social shares can indicate that the content is valuable and engaging enough for users to want to share it with their networks.

    • Comments (If Applicable): For pages that allow comments, track the number of comments received. Engaging content often sparks conversations and discussions, which can be a positive signal of user interest.

  2. Website-Level Engagement Factors:

    • Navigation Depth: Track how many pages users visit within a single session. Deeper navigation (visiting multiple pages) suggests greater engagement.

    • Return Visits: Measure the frequency with which users return to the website, as this indicates a positive user experience and valuable content.

    • Exit Pages: Analyze which pages are frequently the last ones viewed in a session. While some exit pages are expected (e.g., a "Thank You" page after a purchase), if key content pages are frequent exit points, it might signal an issue with user engagement or a lack of clear next steps for the user.

  3. Develop a "Good Click" vs “Bad Click” Scoring System:

    • Assign points to each engagement factor based on its perceived value. For example, reaching 75% scroll depth might be worth more points than spending 30 seconds on a page.

    • Establish a point threshold that determines a "good click." For example, if a user accumulates 10 or more points based on their engagement actions, it's categorized as a good click.

2: Data Collection and Analysis

  1. Implement Tracking: Use website analytics tools (e.g., Google Analytics, Adobe Analytics) to collect data on the defined engagement factors.

  2. Segment Data: Segment your data by page type, traffic source, device type, and other relevant dimensions to gain more granular insights.

  3. Calculate "Good Click" and "Bad Click" Rates: Apply the scoring system and thresholds to determine the percentage of good clicks and bad clicks for each page and segment.

  4. Analyze Correlations: Look for correlations between the “good clicks” and “bad clicks” vs organic search keyword rankings.

3: Actionable Insights and Optimization

  1. Identify High-Performing Content: Pages with high good click rates indicate content that is effectively meeting user needs. Analyze these pages to understand what makes them successful and replicate those strategies.

  2. Improve Low-Performing Content: Pages with high bad click rates or low engagement scores need attention. Use the data to diagnose potential issues (e.g., confusing content, slow loading times, poor mobile experience) and implement improvements.

  3. Experiment and Refine: Continuously test different content formats, page layouts, calls to action, and other elements to see how they impact user engagement and optimize your "good click" rate.

Key Considerations

  • Context is Crucial: The ideal "good click" criteria will vary depending on the specific goals of a page and the type of content it offers.

  • Iterative Approach: This measurement system should be treated as an ongoing experiment. Refine your criteria and thresholds based on your analysis and observations.

  • Qualitative Feedback: Supplement quantitative data with qualitative user feedback (e.g., surveys, polls, user testing) to gain a deeper understanding of user experiences.

4. Building Your Own Site Focus Scoring System with AI Embeddings

The leaked "Content Warehouse" documents hint at Google's use of sophisticated topic analysis to assess site focus. While we can't know their exact methods, we can build a system using AI embeddings to gain similar insights for SEO. Embeddings capture the semantic meaning of text, allowing us to compare content on a deeper level.

Here’s how to build a Site Focus Scoring System leveraging AI embeddings:

1: Define Your Target Topics

  • Keyword Research: Identify the core keywords and phrases representing your topics.

  • Competitor Analysis: See what keywords your competitors target and how they organize their content thematically.

  • User Intent: Consider the search queries people use to find information on your topics, and the content types they seek (informational, transactional, navigational).

2: Generate Embeddings for Each Page

  • Content Extraction: Extract the main content from each page of the websites you're analyzing (your own and competitors). Exclude boilerplate content like headers, footers, and sidebars.

  • AI Embedding Model: Use a pre-trained embedding model like BERT, SentenceTransformers, or OpenAI's embedding API to generate a vector representation (embedding) for each page's content. These embeddings capture the semantic meaning of the text.

3: Calculate a Representative Site Embedding

  • Average Embeddings: Average the embeddings of all pages on a website to create a single representative embedding that encapsulates the overall content focus of the site.

4: Measure Similarity to Target Topics

  • Topic Embeddings: Generate embeddings for your predefined target topics using the same AI model.

  • Cosine Similarity: Calculate the cosine similarity between each website's representative embedding and your target topic embeddings. Cosine similarity measures the angle between two vectors, with higher scores (closer to 1) indicating greater similarity.

5: Analyze Site Focus and Outliers

  • Site Focus Score: The average cosine similarity across all target topics represents the website's overall focus score. A higher score indicates a stronger alignment with your target topics.

  • Outlier Detection: Examine individual page embeddings that have low cosine similarity to the site's representative embedding. These outliers might indicate:

    • Content that deviates from the site's core focus: This could be content on unrelated topics, potentially diluting the site's topical authority.

    • Opportunities for content optimization: These pages might benefit from being rewritten or refocused to better align with the site's core themes.

    • Technical SEO issues: Low similarity could point to pages that are not well-integrated into the site's internal linking structure, potentially impacting their discoverability and relevance.

6: Actionable Insights for SEO

Important: Don't jump to conclusions about outliers! Keep in mind that we don’t know exactly how Google may be using their “siteFocusScore” in practice, so be careful about how you implement changes based on this type of system.

  • Refine Content Strategy: Identify content gaps or areas where your website's focus could be strengthened.

  • Optimize Existing Content: Revise outlier pages to better align with target topics or consider removing or consolidating irrelevant content.

  • Improve Internal Linking: Ensure that pages closely related to the core site focus are well-linked internally, boosting their relevance and authority.

Example:

Imagine you're analyzing websites focused on "dog training." You define target topics like "puppy training," "obedience training," and "dog behavior."

  1. After generating embeddings, you find that Website A has a high site focus score, with its content strongly aligning with your target topics.

  2. Website B has a lower score, and its outlier analysis reveals several pages about "cat care."

  3. This suggests Website B is less focused on "dog training," potentially diluting its topical authority.

Conclusion

The Google Content Warehouse API leak is a game-changer for SEOs. While we can’t treat these function references as absolute truths, they offer invaluable clues about Google’s ever-evolving search algorithms.

The key takeaway? Google is obsessed with understanding and rewarding websites that provide high-quality content, and demonstrable authority, and exceptional user experiences.

By embracing the outlined principles and continually testing and refining your SEO strategies, you can navigate the complexities of Google Search and achieve lasting success.

Let the insights from the leaked documents guide your path to better rankings and a stronger online presence.

Jason Melman
Jason Melman

Founder of SEO Workflows and VP of SEO for DEPT. Expert in SEO, with experience leading teams of SEO practitioners and overseeing the SEO strategy for over 100 small to enterprise-sized brands. Secondary areas of expertise beyond SEO include a mix of database engineering and full-stack web development.