ChatGPT appears to have stopped tagging the links it sends, so since about 9 October its visitors are landing in analytics as "direct".

Schwartz relays Cedric Huesler of Adobe, who reports that GPT-6 opens links with `noopener` and `noreferrer` and no longer adds `utm_source=chatgpt.com`, so the visit is filed as direct. Huesler compared about 500 pages that got at least 5% of visits from ChatGPT, 9 to 13 October against the week before: ChatGPT visits fell by about 31,000 a day and direct visits rose by about 26,000 a day on the same pages. Sébastien Billard separately reports a sharp drop in ChatGPT traffic since 9 October. OpenAI has made no statement, and Schwartz says it is unclear whether the change is intentional. This is practitioner data, not a confirmed OpenAI change.

A beta "Topics Portfolio" tab in the AI Performance report groups the questions where a site is cited into themes, shows roughly how many citations and sites each theme has, and lists "Top Opportunity Queries" where other sites are cited and yours is not. No click data. Microsoft writes "Topics with insufficient site presence or insufficient ecosystem activity are not shown" and "Treat the numbers as directional signals for planning, not as a precise ledger." The post does not name Copilot as the surface measured.

No change. ChatGPT's newest note is still 9 October. Perplexity's changelog has the same October entries and nothing on Sonar. Anthropic's table still shows `claude-sonnet-4-5-20250929` retiring 30 November and `claude-haiku-4-5-20251001` Active with "Not sooner than October 15, 2026", which is tomorrow. The engine's `main` is still `06233ce` with `gpt-5.1` in `src/adapters.ts` and `claude-haiku-4-5` in `src/extract.ts` (checked today).

New since Monday: the source itself. Method: 27.5 million result pages for 660,000+ keywords, 49 countries, desktop and phones. A page counts as poisoned when fewer than half of the keyword's usual top-10 sites appear and they come back later. Baseline 20 August to 9 September. Poisoned pages rose from 0.17% to 8.0% since 13 September, peaking at 27.0% on 29 September and running 5 to 11% a day since 1 October. AI Overviews appeared on 34.9% of poisoned pages against 54.2% normally, and kept their usual sources 42.3% of the time against 68.8%. Nozzle: "Nothing on the page gives it away." and "Comparing against yesterday alone is fragile, because yesterday may have been poisoned too." No Google statement. One vendor's data and definition.

617,985 citations, seven engines, five industries (finance, retail, education, technology, sports brands), US only, 1 to 30 September, 100 buyer questions a day per engine, 295 of 400 containing "best" or "top". Listicles were 66.6% of cited pages. Brands published 38.9% of cited pages and paid or affiliate publishers 36.6%. In Google AI Overviews and AI Mode, forums and video were roughly a quarter of citations, under 3% elsewhere. Otterly: "Publishing your own listicle works, and a third of the market already does it." Limits: vendor data, one month, no service businesses, and Otterly has a paid-placement partner.