AI SEO and Google Core Updates
Google core updates change how pages rank in Search, and AI Overviews and AI Mode draw on pages Google can index and show. But citations and rankings overlap only partly: 37.9% of AI Overview URLs ranked in the top 10 in Ahrefs' March 2026 study. No public study isolates core updates from AI citation changes, so treat any claim as unproven. 38
- Core updates are broad changes to Google's systems, run several times a year, and Google promises no recovery.
- AI Overview citations overlap with top-10 results far less than in 2025, so rank and citation can diverge.
- AI citations also churn on their own: the median page loses half its share in 11 days.
- We found no public study that measures core updates against AI citations. Treat claims as hypotheses.
- Resilience comes from useful, original pages and mentions elsewhere, not from reacting to each update.
How do Google core updates affect AI search visibility?
The effect is real in places and unmeasured in others. Google says pages must be indexed and eligible to show in Search to appear as links in AI Overviews or AI Mode, with no extra technical requirements. 8 A core update that moves your rankings can therefore change what Google's own AI features can draw on. That is our inference, not a Google statement.
Outside Google, the link is weaker. Other assistants run their own searches (Copilot draws on Bing), and the studies below show their citations often come from pages that do not rank for the prompt. We found no public study that tests a core update against AI citation changes, so we cannot give you a number.
What is a Google core update, and how often do they happen?
A core update is a broad change to Google's ranking systems. Google says they happen several times a year, are meant to improve helpful and reliable results overall, and do not target specific sites. 1
Google's status dashboard lists five core updates between March 2025 and May 2026. Each rolled out for about 12 to 18 days. 2 Google also says there is no guarantee that changes you make will lead to a noticeable improvement. 1
Do your Google rankings still predict your AI citations?
Only partly, and less than before. Ahrefs found that 37.9% of AI Overview URLs also ranked in the top 10 in its March 2026 study of 863,000 SERPs. The figure was about 76% in July 2025. 3 Ahrefs suggests the system now leans on related searches it runs behind the scenes.
Other assistants overlap less. In 15,000 long-tail prompts, a simple average of about 12% of cited links across four assistants sat in Google's top 10, with Perplexity highest at 28.6%. 4 For AI Mode, Semrush found about 54% domain overlap and 35% URL overlap with the top 10. 5
So a ranking drop does not automatically mean lost citations, and a ranking win does not secure them.
| Engine | Overlap with Google top 10 | Study |
|---|---|---|
| Google AI Overviews | 37.9% of cited URLs (about 76% in July 2025) | Ahrefs, March 2026, 4M URLs 3 |
| Google AI Mode | About 35% of URLs, 54% of domains | Semrush, July 2025, 5,000 keywords 5 |
| Perplexity | 28.6% of cited URLs | Ahrefs, July 2025 data, 15,000 long-tail prompts 4 |
| ChatGPT, Gemini, Copilot | About 6% to 9% of cited URLs | Ahrefs, same study 4 |
Could AI citations change without any core update?
Yes, and constantly. In data to January 2025, Authoritas tracked 2,104 keywords that showed an AI Overview. Its volatility score for AI Overview citations was higher than for organic rankings, and it said about 70% of cited pages could change over two to three months. 6 Changes in citations were nearly unrelated to changes in organic results, with a correlation of 0.09. 6
Profound looked at 883,000 pages across seven engines for a year. The median page lost half its citation share within 11 days of peaking. 7 Both studies come from vendors of monitoring tools, and both measure citation share, not traffic or sales.
The lesson is that a dip in AI citations during an update window may not be the update. Check the baseline noise first.
What should you do when a core update rolls out?
Wait, measure, then act on evidence. Google advises waiting at least a full week after an update finishes, then comparing the week after with the week before the rollout began. It also says to avoid quick fixes and to treat deleting content as a last resort. 1
Add AI visibility to the same routine. Pages shown in AI Overviews and AI Mode count in the normal Search Console Performance report under Web. 8 Google's generative AI performance report adds impressions for those features by page, country and device, though it shows no clicks. 10
- Before: record your top 20 pages, their Search Console clicks, and your ten tracked AI prompts.
- During: note start and end dates from the Search Status Dashboard. Change nothing big.
- After: wait one full week, then compare the week after against the week before the start.
- Split the result: Web search, AI features impressions, and tracked AI citations.
- Act only on large, sustained drops, and fix helpfulness, not tricks.
What makes a site resilient to updates and AI shifts?
Original, useful pages and a real reputation hold up best. Google's AI guide says to write non-commodity content, meaning material that readers find helpful and reliable and cannot get from a thousand identical pages. 9
Ahrefs' study of 75,000 brands found branded web mentions and YouTube mentions correlated most strongly with AI visibility, though it reports correlation only. Mentions on other sites spread your risk beyond Google's rankings. See brand mentions versus backlinks.
Refresh important pages on a schedule, using our guide to refreshing old content for AI. Rahil Jain runs Chalk Labs' AI SEO programme, whose performance tracking covers rankings, impressions and AI-citation presence side by side, so one dip is not mistaken for the other.
What don't we know yet?
We do not know whether a given core update changes AI citations directly, because we found no public study that tests it. The overlap numbers describe a snapshot, not a cause.
We also do not know how stable the 38% overlap is. It fell sharply in eight months. 3 Re-check the studies before you rely on them, and read AI SEO versus traditional SEO for how the two fit together.
Frequently asked questions
Does a Google core update change what ChatGPT cites?
We found no evidence either way. ChatGPT uses its own retrieval, and Ahrefs found only about 6% to 9% of ChatGPT, Gemini and Copilot citations sat in Google's top 10. 4 A core update may have little direct effect there, but nobody has published a test.
Will recovering from a core update restore my AI Overview citations?
How long should I wait before reacting to a core update?
Where can I see AI Overview performance in Search Console?
Should I rewrite my pages after every update?
No. Google says to avoid quick fixes and focus on sustainable improvements, with deleting content a last resort. 1 Rewriting on a schedule for accuracy and usefulness is sensible. Rewriting in a panic after each update is not.
Sources
- Google Search's core updates and your website · Google Search CentralOpened October 20, 2026. Supports: Core updates are broad changes several times a year; do not target specific sites; wait at least a full week after completion and compare week after with week before; avoid quick fixes; deleting content a last resort; no guarantee changes will lead to improvement. Page last updated 2025-12-10.
- Google Search Status Dashboard: ranking updates history · GoogleOpened October 20, 2026. Supports: Core updates: March 2025 (13 Mar, 13 days 21 hours), June 2025 (30 Jun, 16 days 18 hours), December 2025 (11 Dec, 18 days 2 hours), March 2026 (27 Mar, 12 days 4 hours), May 2026 (21 May, 11 days 21 hours).
- How Many AI Overview Citations Come From the Top 10? (March 2026 update) · AhrefsOpened October 20, 2026. Supports: 863K keyword SERPs and 4M AI Overview URLs; 37.9% of cited URLs also in the top 10; about 76% in July 2025; Ahrefs suggests AI Overviews rely more on fan-out query results. Published 2 March 2026.
- AI search overlap with Google results · AhrefsOpened October 20, 2026. Supports: 15,000 long-tail prompts; Perplexity 28.6% in Google top 10; ChatGPT, Gemini and Copilot between 6.1% and 8.6%; average about 12%. Data collected July 2025; published 11 August 2025.
- How Google's AI Mode Compares to Traditional Search and Other LLMs · SemrushOpened October 20, 2026. Supports: 5,000 keywords; AI Mode cited sources had about 54% domain overlap and 35% URL overlap with Google's top 10. Published 21 July 2025.
- SERP organic and AI Overview volatility research · AuthoritasOpened October 20, 2026. Supports: 2,104 keywords with AI Overviews out of 11,203; AI Overview citation volatility 0.68 and 0.73 versus organic 0.49 and 0.55; about 70% of AI Overview pages could change over 2 to 3 months; correlation 0.09 with organic changes. Vendor study, US desktop, data to January 2025. Published 19 February 2025.
- The half-life of an AI citation is 11 days · ProfoundOpened October 20, 2026. Supports: 883,000 pages across seven answer engines, September 2025 to September 2026; median half-life 11 days; measures Profound's own citation share, not traffic; vendor study. Published 30 September 2026.
- AI features and your website · Google Search CentralOpened October 20, 2026. Supports: Pages must be indexed and eligible to show with a snippet to appear as links in AI Overviews and AI Mode; no additional requirements; query fan-out; AI feature traffic is counted in the Performance report under Web. Page last updated 2025-12-10.
- Optimizing your website for generative AI features on Google Search · Google Search CentralOpened October 20, 2026. Supports: Write non-commodity content that readers find helpful and reliable. Page last updated 2026-07-10.
- Generative AI performance report in Search Console · Google Search Console HelpOpened October 20, 2026. Supports: Report shows impressions only for AI Overviews and AI Mode, by page, country, device and date; may not appear for sites with too few impressions.