
Key takeaways
- A logging error cut reported impressions in the Generative AI performance report for data starting August 13, 2026.
- Google confirmed on its data anomalies page that the issue affects data logging only, not actual Search visibility.
- John Mueller said on Bluesky that Google was working on the fix and would add an annotation inside Search Console to flag the affected dates.
- Search Engine Land reported the data was fixed a few days after the issue was first reported.
Anyone who watched their Generative AI performance report in Search Console dip sharply after August 13 was not looking at a real drop. Google confirmed the numbers themselves were wrong.
What broke
Search Console’s Generative AI performance report, which shows how a site’s pages perform inside AI Overviews and AI Mode, started showing a decrease in impressions for data from August 13, 2026 onward. Google’s data anomalies support page put it plainly: “A logging error caused a decrease in impressions on the Generative AI performance report in Search for data starting on August 13, 2026. This issue affects data logging only and is ongoing.”
Google’s John Mueller added detail on Bluesky: “We’re aware of this issue and working on resolving it. This is just a logging issue and not representative of visibility changes in Search. We’re adding an annotation in Search Console to let folks know about this in the near future.”
Report, not reality
The distinction matters. This was a counting error in how Search Console logged impressions for that report, not a change in how often pages actually surfaced inside AI Overviews or AI Mode. Anyone pulling impression trends for that report during the affected window was working from an undercount, not a signal about declining AI visibility.
Search Engine Land, which covered the bug, later added that Google fixed the data a few days after the issue was reported. Google’s own statement did not include a fix date or a closed end to the affected range, so treat any August 13 onward comparison in that report as needing a recheck against current numbers rather than a fixed answer.
Why we care
If a client or dashboard flagged a sudden AI Overviews or AI Mode impression drop starting mid August 2026, this bug is the first thing to rule out before writing a diagnosis. Pull the Generative AI performance report again now, compare it against what was reported at the time, and watch for the annotation Google said it would add inside Search Console marking the affected range.
The evidence
- Type
- data
- Impact
- medium
- Affects
- Generative AI performance report, Search Console
Sources
- 1.Google Search Console Generative AI Performance Report in Search data bug - Search Engine Land, August 17, 2026Primary
Common questions
Did actual visibility in AI Overviews or AI Mode drop?
No. Google said on its data anomalies page that the issue affects data logging only and is not representative of visibility changes in Search. The report undercounted; the underlying performance did not change.
Which dates are affected?
Data starting August 13, 2026, in the Generative AI performance report for Search. Google did not specify an end date for the affected range in its statement.
Will Search Console flag the affected period?
Google said it would add an annotation inside Search Console to let users know about the issue, though it gave no date for when that annotation would appear.
About the author

Founder, UpgradIQ FZC LLC
Adam Hafez works on technical SEO and search measurement: how pages get crawled, indexed, ranked and now quoted by answer engines. He founded UpgradIQ, which reads Google Search Console and GA4 to tie ranking movement back to the changes that caused it. He publishes what the data supports and states the limits of it.
- Technical SEO
- Search Console and GA4
- Answer engine optimization
- Structured data
The briefing
Only what actually changed in search, delivered in full by RSS, Atom or JSON feed.
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