ChatGPT's clicks now arrive as direct traffic

On Monday we wrote that rank trackers were being fed altered results that look normal. This week the same thing happened one step later, in analytics. The visits are real, the report looks normal, and a growing share of the people who came from ChatGPT are filed under a different name.

ChatGPT's links lost their label

In June OpenAI began adding utm_source=chatgpt.com to links in ChatGPT answers, which let analytics tools count AI referral traffic directly. On 14 October Search Engine Roundtable reported that the tag had started to disappear with GPT-6, which reached ChatGPT on 7–8 October. Cedric Huesler of Adobe found that the links also open without a referrer, so there is nothing left to say where the visit came from.

Huesler's numbers show where the visitors went. On about 500 pages where ChatGPT had driven at least 5% of visits, 9–13 October against the week before: ChatGPT visits fell by about 31,000 a day, and direct visits to the same pages rose by about 26,000. Direct traffic rose on two of every three pages that lost ChatGPT traffic. Search traffic on those pages fell 7%, in line with everything else.

Profound, which collects ChatGPT answers, published a timeline the same day. It ties the change to Intelligent UI, the visual answer format that came with GPT-6.

Profound did not state its sample size, and OpenAI has not commented. Neither source can say whether the change was intended. It runs the other way from Google, which on 1 October was seen adding UTM parameters to links from Gemini.

This is also why referral traffic was never a complete measure of AI visibility. A brand can be named in an answer without a click, and now a click can arrive without a name. What an answer says about you is measured in the answer, not in your analytics.

The full data on poisoned SERPs

Monday's issue quoted Nozzle's headline figure through Search Engine Roundtable. The report itself, dated 10 October, is more precise. Nozzle judged 17.8 million Google results pages collected from 13 September to 9 October across 49 countries, and found 8.0% of them altered, against a baseline of 0.17% from 20 August to 9 September. Its requests started failing on 13 September; the first altered pages appeared on 20 September; the peak came on 29 September at 27.0%. Since 1 October the daily share has ranged from 4.2% to 11.4%.

The altered pages are recognisable only against the keyword's own history. In a normal result, 88.5% of the sites from the previous check are still there; in an altered one, 20.7%. The page features change too.

The first row matters for anyone counting AI Overviews from scraped results: a tracker that took altered pages at face value would have seen AI Overviews appear less often during the peak. Most altered results are short-lived: 80% lasted one check, 15% two in a row, 5% three or more. Google has still not commented.

Bing shows which AI topics you are missing from

On 13 October Microsoft added Topics Portfolio, in beta, to the AI Performance section of Bing Webmaster Tools. It groups the queries a site is cited for in Copilot and Bing's AI answers into topics, and estimates for each topic its size across all sites, the number of sites cited and the number of queries. Below it, a list of opportunity queries shows where other sites are cited and yours is not.

It is the first report from a search engine that puts a site's AI citations beside the whole topic, competitors included. Microsoft is careful about the numbers.

Topics are generated by AI, so a query may land under a label you would not choose, and branded searches can appear as opportunities: Microsoft's own example shows a competitor's brand under "Running Shoes". Small sites may see little or nothing.

ChatGPT cites the original, not the retelling

On 12 October Search Engine Journal reported Ahrefs data on the domains ChatGPT cites most in the US, comparing 2.4 million answers from March with 3.8 million from September. PubMed rose from 64th place to 4th. WebMD fell from 18th to 79th. Britannica, Investopedia and the New York Post left the top 200. Government health and research sites, regulators such as the FDA and product testers such as RTINGS climbed.

Ahrefs' reading is that ChatGPT "seems to be prioritizing original sources over sites that summarize them". Only 14.4% of free, logged-out responses ran a web search at all, and those averaged about 1.6 background queries. Ahrefs warns that this is one model in one period and that a citation rank is not traffic.

For citation share, the lesson is uncomfortable for anyone whose content restates other people's facts: the page that published the number first now wins the citation, in Ahrefs' data, more often than the page that explained it best.

Gemini 4 Argon reaches AI Mode

On 13 October Google began rolling out Gemini 4 Argon in AI Mode for Google AI Pro and Ultra subscribers, who choose it from the "+" menu in the search box. Robby Stein, Google's VP of Product for Search, wrote that it is "rolling out globally in Search" and "brings big improvements to tackling nuanced, multi-step tasks in AI Mode". Free users keep the default model. Google named no languages.

On 14 October Search Engine Roundtable showed Google testing the AI Mode sidebar, with chat history and a new-chat button, on the ordinary results page. Barry Schwartz could not reproduce it, so it is a test for now. Together the two point the same way: AI Mode is becoming the place where paying users get the best model, and the ordinary results page is being fitted with its controls.

Also this week

• PDFs rank like pages. On Search Off the Record, Martin Splitt said Google converts PDFs to HTML before indexing them, so their links count as links, and John Mueller said they "can also appear in AI overviews, AI mode". A PDF whose text cannot be selected and copied cannot rank on that text.
• A migration can come undone after four months. Asked about a site whose new domain lost visibility back to the old one months after a move, Mueller said that "sometimes things just take a particularly long time to be fully processed" and recommended a change of address for both the www and non-www versions.
• ChatGPT ads get human account managers. On 14 October an advertiser posted an OpenAI email introducing a "ChatGPT Ads Account Manager" with biweekly check-ins.

Sources

Every claim above is dated and linked. Where a number comes from a measurement rather than an announcement, whoever measured it is named.

• OpenAI Drops UTM Parameters From ChatGPT Results (GPT-6) — Search Engine Roundtable, on Cedric Huesler's data, 14 October 2026
• ChatGPT's missing UTM tags: what our research shows — Profound, 14 October 2026
• Google Gemini Adds UTM Parameters For Referral Attribution — Search Engine Journal, 1 October 2026
• Poisoned Google SERPs — Nozzle, 10 October 2026
• Analysis: Google Is Poisoning Search Results For Rank Trackers — Search Engine Journal, 14 October 2026
• Topics Portfolio (beta) in AI Performance — Bing Webmaster Blog, 13 October 2026
• Bing Webmaster Tools Sorts AI Search Queries Into Topics — Search Engine Journal, 13 October 2026
• ChatGPT's Most-Cited Sites Tilt Toward Primary Sources, Data Shows — Search Engine Journal, 12 October 2026
• Query fan-out in ChatGPT: research — Ahrefs
• Introducing Gemini 4 Argon — Google, 13 October 2026
• Google Adds Gemini 4 Argon To AI Mode For Pro & Ultra Subscribers — Search Engine Journal, 13 October 2026
• Google Tests AI Mode Left Sidebar On Main Google Search Results Page — Search Engine Roundtable, 14 October 2026
• Google Explains How They Rank PDFs And What It Means For SEO/GEO — Search Engine Journal, 14 October 2026
• Google Says Why Site Migrations Can Exceed 4 Months — Search Engine Journal, 13 October 2026
• OpenAI ChatGPT Ads Account Manager Representatives — Search Engine Roundtable, 14 October 2026