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Appendix C — Change ledger & citation map

The Technical SEO Reference · generated from ../research/citations/ · all fetch dates 2026-08-04

C.1 The 2024–2026 change ledger

The dated feature/policy/doc changes are distributed through the chapters and merged in Appendix B (deprecations) and each chapter's sources. The marquee changes that reshaped doctrine in this window:

Date Change Ch
Dec 2024 Crawling December series: WRS 30-day cache, resource crawl-budget billing, CDN crawl mechanics, faceted-navigation doc 6, 4, 10
Jan 2025 Breadcrumbs off mobile SERPs 10
Feb 2025 CrUX: LCP subparts, RTT; ECT retired 15
Mar–Jun 2025 Structured-data phase-outs announced (Jun 12 'Simplifying the search results page': seven types) 12
Sept 2025 SD mass doc removal 12
Nov 2025 Crawling docs migrate to /crawling/; CrUX Dashboard deprecated; practice-problems notice; Dataset clarification; GBP Q&A retired 2–5, 15, 12
Dec 2025 JS clarifications: noindex-skips-rendering, JS canonicals, non-200 render skips 6
Feb 2026 2MB Googlebot fetch limit documented; IP-range JSONs relocated 2, 5
Mar 2026 'Inside Googlebot' disclosures; preferred-image mechanism; Google-Agent; robots-meta outside-head note 2, 6, 14, 5, 7
Apr 2026 Chrome 147 HTTPS-by-default (ESB users) 17
May 2026 FAQ rich results effective end (May 7); Web Bot Auth experiment 12, 5
Jun 2026 FAQ docs removed (Jun 15); GSC gen-AI reports + toggle (Jun 3); site-move all-variants CoA rule (Jun 17) 12, 16, playbook
Jul 2026 Platform properties (Jul 7/29); canonicalization re-evaluation changelog (Jul 10); GeminiNotebook rename (Jul 14); review-snippet incentivized-review rule (Jul 24) 19, 8, 5, 12
Oct 2026 (scheduled) Chrome 154: HTTPS-by-default for all 17

C.2 URL-migration table

See Appendix B §B.4 — maintained there to keep one home.

C.3 Citation index

Every source cited in Chs 2–21, with the page's own last-updated stamp where shown. Re-verify at any press/audit pass — help-center pages expose no revision dates and can drift silently.

Source Page last-updated Cited in
Content Independence Day (Cloudflare, Jul 1, 2025) 2025-07-01 Ch 05
Introducing pay per crawl (Cloudflare, Jul 1, 2025) 2025-07-01 Ch 05
Perplexity is using stealth, undeclared crawlers to evade website no-crawl direc 2026-07-15 (modified; originally 2025-08-04) Ch 05
Forget IPs: using cryptography to verify bot and agent traffic 2026-07-15 Ch 05
New opportunities, control and insights for website owners (blog.google, Jun 3, 2026-06-03 Ch 05, Ch 07
HTTPS by default (Oct 28, 2025 — Chrome/Google security blog; security.googleblo 2025-10-28 Ch 17
CCBot - Common Crawl Ch 05
RFC 9309: Robots Exclusion Protocol (REP) — IETF Proposed Standard, September 20 Published: September 2022 Ch 03
Amazonbot Ch 05
CrUX overview 2024-02-08 Ch 15
CrUX API 2025-02-11 Ch 15
CrUX on BigQuery 2025-02-11 Ch 15
CrUX methodology 2024-06-20 Ch 15
CrUX dimensions 2025-02-11 Ch 15
CrUX metrics November 18, 2025 (footer 2025-11-28) Ch 15
CrUX release notes 2026-07-14 Ch 15
Reduce the impact of third-party code (Lighthouse) 2019-05-02 Ch 15
Does not have a tag (Lighthouse) 2024-05-27 Ch 15
Prerender pages in Chrome (Speculation Rules API) 2026-01-23 Ch 15
Meta web crawlers Ch 05
Things to know about Google's web crawling 2026-03-03 UTC Ch 02, Ch 04
Crawling docs changelog Ch 02, Ch 05
Optimize your crawl budget 2026-07-22 UTC Ch 02, Ch 04, Ch 10
Google's common crawlers 2026-07-14 Ch 05, Ch 14
Google's special-case crawlers 2026-02-11 Ch 03, Ch 05
Google's user-triggered fetchers 2026-07-16 Ch 03, Ch 05
Overview of Google crawlers and fetchers (user agents) 2026-06-12 UTC Ch 02, Ch 03, Ch 04, Ch 05
Reduce Google crawl rate 2025-12-18 UTC Ch 02, Ch 04, Ch 16
Verify requests from Google crawlers and fetchers 2026-03-20 Ch 05
Authenticate requests with Web Bot Auth (experimental) 2026-05-04 Ch 05
[Managing crawling of faceted navigation URLs Google Crawling docs (moved from ](https://developers.google.com/crawling/docs/faceted-navigation) 2025-12-18
Myths and facts about crawling 2025-12-18 UTC Ch 02, Ch 03
How to write and submit a robots.txt file 2025-11-21 Ch 03
How Google interprets the robots.txt specification 2026-07-08 Ch 03, Ch 04, Ch 05
Submit an updated robots.txt file 2025-11-21 Ch 03
List of useful robots.txt rules 2026-06-12 Ch 03
Debug DNS and network errors 2025-12-18 UTC Ch 02, Ch 04
How HTTP status codes affect Google's crawlers 2026-02-04 UTC Ch 02, Ch 04, Ch 07, Ch 16
[Indexing API Quickstart Google for Developers](https://developers.google.com/search/apis/indexing-api/v3/quickstart) 2026-07-16 UTC
To infinity and beyond? No! (Google Search Central Blog) 2008-08-05 (post date) Ch 04
[Handling legitimate cross-domain content duplication Google Search Central Blo](https://developers.google.com/search/blog/2009/12/handling-legitimate-cross-domain)
To slash or not to slash (Google Search Central Blog, Apr 21, 2010 — still live) 2010-04-21 Ch 10
HTTPS as a ranking signal (blog, Aug 2014 — historical) August 2014 Ch 15, Ch 17
Google's handling of new top level domains — Google Search Central Blog (John Mu Ch 11
Deprecating our AJAX crawling scheme 2015-10-14 Ch 06
Indexing HTTPS pages by default (Dec 2015) Ch 17
[Consolidating your website traffic on canonical URLs Google Search Central Blo](https://developers.google.com/search/blog/2019/02/consolidating-your-website-traffic-on)
[Bye Bye Preferred Domain setting Google Search Central Blog (Jun 18, 2019)](https://developers.google.com/search/blog/2019/06/bye-bye-preferred-domain-setting)
A note on unsupported rules in robots.txt (Google Search Central Blog, July 2019 Ch 03
New robots tag: indexifembedded (Google Search Central Blog) 2022-01-21 Ch 07
[Spring cleaning: the URL Parameters tool Google Search Central Blog (Mar 28, 2](https://developers.google.com/search/blog/2022/03/url-parameters-tool-deprecated)
The role of page experience in creating helpful content (blog, April 19, 2023) April 19, 2023 (with Nov 8, 2023 and Jan 31, 2024 update notes) Ch 15
[Sitemaps ping endpoint is going away Google Search Central Blog (Gary Illyes, ](https://developers.google.com/search/blog/2023/06/sitemaps-lastmod-ping) Posted Monday, June 26, 2023; banner: "The sitemaps ping endpoint deprecation is complete."
Mobile-first indexing has landed - thanks for all your support (blog, Oct 31, 20 October 31, 2023 Ch 15
Upcoming deprecation of Crawl Rate Limiter Tool in Search Console posted 2023-11-24 Ch 02, Ch 16
Mobile-indexing-vLast-final-final.doc (blog, June 3, 2024) June 3, 2024 Ch 15
[Farewell, Sitelinks Search Box Google Search Central Blog](https://developers.google.com/search/blog/2024/10/sitelinks-search-box) 2024-10
Crawling December: HTTP caching (Gary Illyes) posted 2024-12-09 Ch 02
Crawling December: CDNs and crawling (Martin Splitt & Gary Illyes) posted 2024-12-24 Ch 02, Ch 04, Ch 16
Crawling December: Faceted navigation (Google Search Central Blog, Gary Illyes, 2024-12-17 Ch 10
Crawling December: The how and why of Googlebot crawling posted 2024-12-03, in-post update 2024-12-06 Ch 02, Ch 04, Ch 06
Simplifying the visible URL element on mobile search results (Google Search Cent 2025-01-23 Ch 10
Inside Googlebot: demystifying crawling, fetching, and the bytes we process 2026-03-31 Ch 06
New Location for the Google Crawlers' IP Range Files (Search Central Blog, Mar 3 2026-03-31 Ch 05
Platform properties roll out globally, plus a new social and video performance g Ch 14
AI features and your website 2025-12-10 Ch 05, Ch 07, Ch 12
Intrusive dialogs and interstitials 2025-12-10 Ch 15
Core Web Vitals (Search Central) 2025-12-10 Ch 15
Enable Web Stories on Google 2026-07-01 UTC Ch 14
Define a Favicon to Show in Search Results 2026-02-04 UTC Ch 14
Google Discover and Your Website 2026-03-09 UTC Ch 14
Google Image SEO Best Practices 2026-03-02 UTC Ch 14
Understanding page experience in Google Search results 2025-12-10 Ch 15, Ch 17
Publication dates (byline dates) 2025-12-10 Ch 13
A guide to Google Search ranking systems 2025-12-10 Ch 15
Site names 2025-12-10 Ch 13
Sitelinks 2025-12-10 Ch 13
Snippets and meta descriptions 2026-04-20 Ch 13
[Schema Markup Testing Tool Google Search Central](https://developers.google.com/search/docs/appearance/structured-data)
[Book Actions Structured Data Google Search Central](https://developers.google.com/search/docs/appearance/structured-data/book) 2025-12-10
Breadcrumb (BreadcrumbList) structured data 2025-12-10 Ch 10
[Structured data carousels (beta) Google Search Central](https://developers.google.com/search/docs/appearance/structured-data/carousels-beta) 2026-01-21
[Fact Check (ClaimReview) Structured Data Google Search Central](https://developers.google.com/search/docs/appearance/structured-data/factcheck) 2025-12-10
Generate structured data with JavaScript 2025-12-10 Ch 06, Ch 12
Image Metadata in Google Images (Licensable) 2025-12-10 UTC Ch 14
[Intro to How Structured Data Markup Works Google Search Central](https://developers.google.com/search/docs/appearance/structured-data/intro-structured-data) 2025-12-10
[Local Business (LocalBusiness) Structured Data Google Search Central](https://developers.google.com/search/docs/appearance/structured-data/local-business) 2025-12-10
Merchant listing structured data — Google Search Central Ch 11
[Organization (Organization) Structured Data Google Search Central](https://developers.google.com/search/docs/appearance/structured-data/organization) 2026-04-15
[General Structured Data Guidelines Google Search Central](https://developers.google.com/search/docs/appearance/structured-data/sd-policies) 2026-07-10
Structured Data Markup that Google Search Supports (search gallery) 2026-06-15 Ch 12
Video (VideoObject, Clip, BroadcastEvent, SeekToAction) Structured Data 2026-02-13 UTC Ch 14
Title links 2025-12-10 Ch 13
Translated results in Google Search — Google Search Central Last updated 2025-12-10 UTC Ch 11
Video SEO Best Practices 2025-12-18 UTC Ch 14
[Redirects and Google Search Google Search Central](https://developers.google.com/search/docs/crawling-indexing/301-redirects) 2026-04-14
Block Search indexing with noindex 2025-12-10 Ch 07
[What is URL canonicalization Google Search Central](https://developers.google.com/search/docs/crawling-indexing/canonicalization) 2026-07-10
[Fix canonicalization issues Google Search Central](https://developers.google.com/search/docs/crawling-indexing/canonicalization-troubleshooting) 2026-07-10
[How to specify a canonical with rel="canonical" and other methods Google Searc](https://developers.google.com/search/docs/crawling-indexing/consolidate-duplicate-urls) 2026-07-10
Control what you share with Google 2025-12-10 Ch 07
Googlebot 2026-02-03 UTC Ch 02, Ch 06
File types indexable by Google (301 target of support.google.com/webmasters/answ 2026-02-03 UTC Ch 02
Dynamic rendering as a workaround 2025-12-10 Ch 06
Fix search-related JavaScript problems 2025-12-18 Ch 06
Understand the JavaScript SEO basics 2026-03-04 Ch 06, Ch 07
Fix lazy-loaded content 2025-12-10 Ch 06, Ch 10, Ch 14
Large site owner's guide to managing your crawl budget 2026-07-22 Ch 03, Ch 09, Ch 16
SEO best practices for links 2025-12-10 Ch 06, Ch 10
Mobile site and mobile-first indexing best practices 2025-12-10 Ch 15
Temporarily pause or disable a website Last updated 2025-12-10 UTC. Ch 16
Prevent Images on Your Page from Appearing in Search Results (moved from /search 2025-12-10 UTC Ch 14
Remove a page hosted on your site from Google 2025-12-10 Ch 07
Robots meta tag, data-nosnippet, and X-Robots-Tag specifications 2026-03-24 Ch 06, Ch 07, Ch 14
Introduction to robots.txt 2025-12-10 Ch 03, Ch 07
Old robots.txt spec URL (redirect check only) Ch 03
SEO Guidelines for Explicit Content (SafeSearch) 2025-12-10 UTC Ch 14
Changing your hosting (site move with no URL changes) Last updated 2025-12-10 UTC. Ch 16
Site moves with URL changes 2026-06-17 UTC Ch 02, Ch 16, Ch 17
[Build and submit a sitemap Google Search Central](https://developers.google.com/search/docs/crawling-indexing/sitemaps/build-sitemap) 2026-07-08 UTC
[Combining sitemap extensions Google Search Central](https://developers.google.com/search/docs/crawling-indexing/sitemaps/combine-sitemap-extensions) 2025-12-10 UTC
[Image sitemaps Google Search Central](https://developers.google.com/search/docs/crawling-indexing/sitemaps/image-sitemaps) 2025-12-10 UTC
[Manage your sitemaps with a sitemap index file Google Search Central](https://developers.google.com/search/docs/crawling-indexing/sitemaps/large-sitemaps) 2025-12-10 UTC
[News sitemaps Google Search Central](https://developers.google.com/search/docs/crawling-indexing/sitemaps/news-sitemap) 2025-12-10 UTC
[What is a sitemap? Google Search Central](https://developers.google.com/search/docs/crawling-indexing/sitemaps/overview) 2025-12-10 UTC
[Video sitemaps and alternatives Google Search Central](https://developers.google.com/search/docs/crawling-indexing/sitemaps/video-sitemaps) 2026-05-20 UTC
Troubleshoot Google Search crawling errors 2025-12-18 UTC Ch 02
[URL structure best practices for Google Google Search Central](https://developers.google.com/search/docs/crawling-indexing/url-structure) 2025-12-10
Verify requests from Google crawlers and fetchers 2026-03-20 UTC Ch 17
Minimize A/B testing impact in Google Search Last updated 2025-12-10 UTC. Ch 16
Spam policies for Google web search 2026-05-15 UTC Ch 04, Ch 08, Ch 16, Ch 17
AI optimization: how to optimize for Google Search's generative AI features 2026-07-10 Ch 05, Ch 12
In-depth guide to how Google Search works 2025-12-18 UTC Ch 02
Search Engine Optimization (SEO) Starter Guide 2025-12-10 Ch 10
Malware and unwanted software 2025-12-10 UTC Ch 17
Preventing malware infection 2025-12-10 UTC Ch 17
Google Safe Browsing Repeat Offenders Policy 2025-12-10 UTC Ch 17
Social engineering (phishing and deceptive sites) 2025-12-10 UTC Ch 17
Designing a URL structure for ecommerce websites 2025-12-10 Ch 10
Help Google understand your ecommerce website structure 2025-12-10 Ch 10
Pagination, incremental page loading, and Search 2025-12-10 Ch 06, Ch 10
Overview of international and multilingual site topics — Google Search Central Ch 11
How Google crawls locale-adaptive pages — Google Search Central Last updated 2025-12-10 UTC Ch 11
[Localized versions of your pages Google Search Central](https://developers.google.com/search/docs/specialty/international/localized-versions) 2025-12-22
Managing multi-regional and multilingual sites — Google Search Central Last updated 2025-12-10 UTC Ch 11
Google Search Central documentation updates (Dec 18, 2025 entry) Ch 02, Ch 03, Ch 05, Ch 07, Ch 08, Ch 09, Ch 10, Ch 11, Ch 12, Ch 14, Ch 15, Ch 16
About PageSpeed Insights 2024-10-21 Ch 15
Google Public DNS — Frequently Asked Questions (DNSSEC section) (no date shown) Ch 04
OpenAI bots (platform.openai.com/docs/bots 301s here) Ch 05
Perplexity crawlers (PerplexityBot, Perplexity-User) Ch 05
Google robots.txt parser and matcher library (open source) Ch 03
HSTS Preload List Submission (Chrome-run) Ch 17
The /llms.txt file proposal 2024-09-03 Ch 05
The Open Graph Protocol (STANDARD — originally created at Facebook) Ch 14
Google Safe Browsing Ch 17
Search Off the Record — SEO summer: index waves, sandboxes, and more! (official 2020-08-25 Ch 06
About Applebot - Apple Support Ch 05
Does Anthropic crawl data from the web, and how can site owners block the crawle 2026-04-07 Ch 05
Report Content for Legal Reasons Ch 07
Announcements - Publisher Center Help "An update on publication pages" published April 25, 2024 (updated December 18, 2024) Ch 09
Google News transitions to automatically-generated publication pages - Publisher Published February 10, 2025; Updated March 20, 2025 Ch 09
Help Google News discover your web crawled content - Publisher Center Help Ch 09
Avoid article duplication in Google News - Publisher Center Help Ch 08
News content across Google - Publisher Center Help Ch 09
Appear on other News surfaces - Publisher Center Help Ch 09
HTTPS report - Search Console Help Ch 17
The International Targeting report is deprecated — Search Console Help Ch 11
Search generative AI control - Search Console Help Ch 05, Ch 07
Add a website property to Search Console (property types) (support.google.com shows no revision date) Ch 04
robots.txt report - Search Console Help Ch 03
Page indexing report - Search Console Help Ch 03, Ch 07, Ch 08
Rich Results Test (Search Console Help) Ch 12
Sitemaps report - Search Console Help Ch 09
Rich result status reports (Search Console Help) Ch 12
URL Inspection tool (Search Console Help) Ch 06, Ch 07, Ch 08, Ch 17
Security issues report - Search Console Help Ch 17
Manual Actions report (Search Console Help) Ch 12, Ch 17
Core Web Vitals report (Search Console Help) Ch 15
Change of Address tool - Search Console Help Ch 16
Video Indexing Report - Search Console Help Ch 14
Crawl Stats report - Search Console Help Ch 02, Ch 03, Ch 04
Removals and SafeSearch reports tool - Search Console Help Ch 07, Ch 14
"This site may be hacked" message - Google Search Help Ch 17
"This site may harm your computer" notification - Google Search Help Ch 17
Refresh outdated content - Google Search Help Ch 07
Search Off the Record — 9th episode, official Google transcript PDF (via goo.gle Ch 08
How Google handles JavaScript throughout the indexing process (MERJ/Vercel) posted 2024-07-31 Ch 02, Ch 06
Clean and maintain your site 2015-01-01 UTC Ch 17
Cumulative Layout Shift (CLS) 2023-04-12 Ch 15
Enable HTTPS on your servers 2015-03-27 UTC Ch 17
First Input Delay (FID) 2024-10-06 Ch 15
Fix the cloaked keywords and links hack 2015-01-01 UTC Ch 17
Fix the gibberish hack 2015-01-01 UTC Ch 17
Fix the Japanese keyword hack 2015-01-01 UTC Ch 17
Fixing mixed content 2019-09-07 UTC Ch 17
Help, I think I've been hacked 2015-01-01 UTC Ch 17
Hacked with malware 2015-01-01 UTC Ch 17
How do I know if my site was hacked? 2015-01-01 UTC Ch 17
Identify the vulnerability 2015-01-01 UTC Ch 17
Interaction to Next Paint (INP) September 2, 2025 Ch 15
Why lab and field data can be different (and what to do about it) 2022-07-18 Ch 15
Largest Contentful Paint (LCP) September 4, 2025 Ch 15
Optimize Cumulative Layout Shift 2025-02-07 Ch 15
Optimize Interaction to Next Paint 2025-09-02 Ch 15
Optimize Largest Contentful Paint March 31, 2025 Ch 15
Optimize long tasks December 19, 2024 Ch 15
Quarantine your site 2015-01-01 UTC Ch 17
Rendering on the web 2026-01-05 Ch 06
Request a review (hacked sites) 2015-01-01 UTC Ch 17
Top ways websites get hacked by spammers 2015-01-01 UTC Ch 17
Time to First Byte (TTFB) November 18, 2025 (page footer: 2025-11-28) Ch 15
Web Vitals October 31, 2024 Ch 15
What is mixed content? 2019-09-07 UTC Ch 17
Retired Google sitemaps ping endpoint (live response test) Ch 09
[FAQ IndexNow.org](https://www.indexnow.org/faq)
What Is Edge SEO & Why You Should Adopt It (Search Engine Journal, Dan Taylor) — 2018-12-19 (publication date) Ch 04
Google 404 vs 410 status codes (Mueller office-hours transcription, May 2018; re Ch 02
Google's Gary Illyes On AI, Site Migrations, & 'SEO Is Dead' Claims (Search Engi Ch 16
Google On How They Treat Subdomains vs Subdirectories In 2016 (Search Engine Rou 2016-08-04 (article date) Ch 04
sitemaps.org — Sitemaps XML protocol (v0.9) Last Updated: Monday, November 21, 2016 Ch 09
Taming AI content crawlers (The Register, Jul 30, 2024, Thomas Claburn) — carrie 2024-07-30 Ch 05
How to make your content shine on Google Search (Chrome Dev Summit 2019) — Split 2019-11-13 Ch 06
English Google Webmaster Central office-hours hangout (2017; Mueller on long-ter Ch 07
English Google Webmaster Central office-hours hangout (May 2018; Mueller on 410 Ch 07

224 unique sources. Chapters 18–21 cite additionally from live fetches recorded in their Sources sections (manual-actions help, spam policies, property types, bulk export, API limits, debugging-traffic-drops, prerender-pages, display-layer docs).