Many ChatGPT links lost their UTM tag, utm_source=chatgpt.com, after OpenAI’s October 7 release of GPT-6 and Intelligent UI, and two vendors explain it differently. Adobe’s Cedric Huesler says GPT-6 opens links without a tag or a referrer, and Adobe’s index of tracked ChatGPT visits fell 67% in a week. Profound says the loss sits in answers rendered with Intelligent UI: on October 14, about two thirds of the cited answers it collected still had at least one tagged link.
Adobe: GPT-6 Opens Links Without Tag or Referrer
Search Engine Roundtable quoted Huesler’s LinkedIn post on October 14. He writes that GPT-6 “opens links with window.open(url, "_blank", "noopener,noreferrer") and drops ?utm_source=chatgpt.com.”
Adobe’s chart tracks ChatGPT visits across thousands of sites, indexed so that September 28 to October 7 equals 100. The index peaked at 110 around October 6 and stood at 36 on October 13, which Adobe labels “−67% vs a week earlier”.
On about 500 pages where ChatGPT drove at least 5% of visits, Huesler compared daily visits for October 9 to 13 with the week before:
- ChatGPT: 31k fewer visits per day.
- Direct: 26k more visits per day.
- Search: down 7%, which Huesler calls “the same as everywhere else”.
Adobe’s chart caption says “most”, not all, of what ChatGPT lost shows up as direct on the same pages. Direct rose on 261 of the 387 pages that lost ChatGPT visits, against 49% of pages the week before. On mobile, the share of Direct visitors on ChatGPT-heavy pages who were new to the site rose from 36% to 44%. For ChatGPT visitors, that share is 55%.
Huesler’s caveats: only a few days of sampled data, and a signal visible only on pages where ChatGPT was a large share of traffic. He says it might be a bug.
Profound: The Loss Follows Intelligent UI
Profound’s post, by Josh Blyskal on October 14, measures a different thing: answers it collected, not visits. On October 8, about 98% of collected answers with citations had at least one tagged source link. That fell to 75% on October 9 and 66% by October 14.
Intelligent UI went from 2% of collected answers on October 8 to 26% the next day and about 35% on October 14. Profound’s scatter plot puts the slope near −0.94: about one point less tagging per point of Intelligent UI share.
Profound’s assessment is that the referral decline “is due to this change in how ChatGPT renders links.” In follow-up checks, Profound found links shown after opening an extra product or information panel that still carried tags, while a link displayed directly in an answer could lack one. Attribution can depend on which link a person clicks.
The 66% is a share of cited answers, not of links or of clicks.
Why is ChatGPT traffic showing up as Direct?
Adobe’s Cedric Huesler says GPT-6 links open without a UTM tag or a referrer, so analytics has nothing to attribute and files the visit as direct. Google Analytics describes Direct as users arriving “via a saved link or by entering your URL”. Profound attributes the missing tags to Intelligent UI rendering instead, and we found no OpenAI statement confirming either.
One Release, Two Readings
OpenAI’s release notes list GPT-6 and Intelligent UI in one entry dated October 7. The entry says the rollout starts that day for Plus, Pro, Business and Enterprise and expands to Free and Go from the next day. The entry says nothing about links, UTM parameters, referrers or publishers. Both features shipped together, so the date cannot separate the two explanations.
The units differ (visits vs answers), so Adobe’s and Profound’s numbers cannot be compared directly. Adobe describes how GPT-6 opens links; Profound describes a partial loss that depends on the answer format and on the link clicked.
OpenAI’s Publishers and Developers FAQ said “ChatGPT automatically includes the UTM parameter utm_source=chatgpt.com in referral URLs”, according to a Wayback capture from October 4. On October 15, the FAQ’s original URL redirects to an article on the retirement of the Atlas browser, which does not mention UTM parameters. We cannot say when the redirect began or whether it relates to the tag change.
What to Do in Reports Now
Annotate the break first: Adobe’s chart dates the GPT-6 rollout October 8 to 10, and Profound says around October 9.
- Report ChatGPT and Direct together, as Huesler advises.
- Watch Direct on deep pages that ChatGPT used to send traffic to.
- Profound notes that restoring the tags would improve future reporting but would not automatically recover the missing history.
Links you publish yourself keep whatever tags you put on them, and a UTM builder keeps those tags consistent. For how GA4 buckets AI referrals when a referrer does arrive, see our note on the GA4 AI Assistant default channel.
