The AI Visibility Brief: June 29 - July 5, 2026

THIS WEEK

• A randomized experiment finds Google's AI summaries cut clicks to websites by about 40%
• Cloudflare will block AI crawlers by default on new ad-supported websites
• A 379,000-citation study finds Claude leans on companies' own websites and cites Reddit zero times
• Google's AI answers are spreading fastest on purchase-research searches and cluster on the most expensive keywords

01

A randomized experiment finds Google's AI summaries cut clicks to websites by about 40%

Researchers at the Indian School of Business and Carnegie Mellon built a browser extension that randomly hid Google's AI Overviews (the AI-written summary at the top of search results) for some people and left them on for others, then followed 1,065 US Chrome users through 68,089 real searches. They describe it as the first randomized test of the feature. When the summary appeared, clicks out to websites fell 39.8%, from 0.62 clicks per search to 0.37, and the share of searches ending with no click at all rose from 54% to 73%. People who did not see the summary clicked through to more websites, and they spent as much time reading those websites as any other visitor. Both groups came away equally satisfied with their searches. The panel was desktop Chrome users only, so mobile behavior is untested.

We think this matters because a website can keep its rankings and still lose traffic. When the AI summary appears, people get their answer from it and never click the results underneath, so a traffic drop can happen without anything on the website changing.

Businesses should act on this by working to get quoted inside the summary itself, since those links are the only ones many searchers still click. Getting quoted starts with pages that answer the exact questions customers ask, plainly and near the top of the page.

02

Cloudflare will block AI crawlers by default on new ad-supported websites

Cloudflare, which sits in front of more than 20% of the web, announced three changes on July 1. Every customer, including free plans, now gets separate switches for Search, Agent, and Training crawlers (the bots that read pages for search results, for AI tools acting on a user's behalf, and for model training). From September 15, new domains joining Cloudflare will have Training and Agent bots blocked by default on pages that show ads. And Cloudflare is moving from charging AI companies to crawl toward paying publishers when their content gets cited, starting with partners Ceramic.ai and You.com. Google, Apple, and Microsoft run crawlers that mix search with AI work, so a website that blocks Training shuts those crawlers out entirely and can drop out of the pool of websites Google's AI answers and ChatGPT's web search draw from. The new defaults are enforced on Cloudflare's own network, so they do not depend on any crawler choosing to cooperate.

We think this matters because many businesses will get these blocks by default, without anyone at the company choosing them. A website AI cannot read cannot be cited in AI answers, so a hosting setting now quietly affects how a brand shows up in them.

Businesses should act on this by checking whether their website runs through Cloudflare and, if it does, reviewing the new AI crawler switches before the September 15 defaults land. A wrongly set switch can take a website out of the sources AI answers cite.

03

A 379,000-citation study finds Claude leans on companies' own websites and cites Reddit zero times

Otterly, which sells AI search tracking and added Claude coverage in June, analyzed 379,321 citations Claude produced across 16,406 domains in a month of software and technology prompts. Company and product websites took 64% of the total, more than four times the share of news and media at about 15%. Social media was under 1%, and Reddit did not appear once. Only 13% of the domains Claude cited overlapped with the ones ChatGPT draws on. The data covers tech questions only and was gathered before Claude Sonnet 5 became the default model on June 30, so the mix may move.

We think this matters because Claude gives a company's own website the weight other tools give Reddit and community threads. The work that earns a brand mentions in ChatGPT does close to nothing here, so which tools a brand's buyers use should decide where the effort goes.

Businesses should act on this by writing their product and comparison pages as clear, factual reference material, since a company's own website is the main route into Claude's answers, and checking Claude separately from the tools they already watch.

04

Google's AI answers are spreading fastest on purchase-research searches and cluster on the most expensive keywords

Semrush, which sells search and AI visibility software, tracked more than 600,000 US desktop keywords across 10 industries from November 2025 through April 2026. The fastest growth was on purchase-research searches, the 'best X vs Y' comparisons people run before buying: the share of those searches showing a Google AI Overview grew 71% in six months. Searches made at the moment of buying barely changed. The AI summaries also land hardest on the keywords advertisers pay the most for. In jobs and education, searches with an AI Overview cost advertisers $5.02 per click on average, against $1.51 for searches without one. Keyword volumes and ad costs are Semrush's estimates, not Google's reported numbers.

We think this matters because AI answers are showing up exactly where buyers compare options before they spend. A business can rank first and run the top ad on a search, and the AI summary still sits above both and frames the choice.

Businesses should act on this by earning a place in the independent reviews and comparison roundups these summaries quote. The AI builds its shortlist from the websites that already compare options in a category, and a brand absent from those pages is easy to leave off it.

Thanks for reading this week’s newsletter.
Sincerely,
Brett