A ranking movement cannot always be explained by a single algorithm update. This record pairs official rollout dates with independent observations, helping you align dates and assess the limits of the evidence before diagnosing a site.
GOOGLE SEARCH / RANKING CHRONICLE
The timeline. The evidence.
Read official rollout dates alongside independent observations.
Google Search Status Dashboard · Content revised
28Updates recorded
16Core updates
12Spam and link spam updates
2026
- Start 09:15 — End 01:00 US/PacificSPAM Rollout complete
September 2026 spam update
Official Google dates · 13d 15h 45m
Limited attribution · Research reviewed
Geology observed a US impression drop beginning September 18, six days before rollout. Its GSC sample does not establish a ranking loss attributable to this update.
Scope, limitations and sources
- Observed scope
- US, UK, India / managed properties / rollout versus prior 14 days and September 11–23 / GSC impressions and clicks
- Limitations
- Not representative. Impressions are not rankings; the automated-search explanation is an author inference.
- Start 09:27 — End 01:49 US/PacificSPAM Rollout complete
August 2026 spam update
Official Google dates · 2d 16h 22m
Observed evidence · Research reviewed
In Previsible’s roughly 25,000 query pairs, 16% of queries initially at positions 7–10 moved to page two, versus 0.4% in the top three.
Scope, limitations and sources
- Observed scope
- US desktop web / client GSC / August 4–17 versus August 22–September 4 / average-position bands
- Limitations
- Selected client sample; before/after comparison does not prove causality or generalize to other markets or devices.
- Start 09:00 — End 10:00 US/PacificSPAM Rollout complete
June 2026 spam update
Official Google dates · 2d 1h 0m
Evidence insufficient · Research reviewed
Official completion is confirmed. This review did not find a usable independent post-rollout ranking study with a clear period, sample and metric.
Scope, limitations and sources
- Observed scope
- Public research and original-measurement searches by update name
- Limitations
- This does not establish no impact or stable rankings. No impact size or affected sector is inferred.
- Start 08:40 — End 05:40 US/PacificCORE Rollout complete
May 2026 core update
Official Google dates · 11d 21h 0m
Observed evidence · Research reviewed
SISTRIX reported little overall change across 451 UK ecommerce domains but a net decline across 77 news domains, showing sector differences.
Scope, limitations and sources
- Observed scope
- UK / SISTRIX visibility / May rollout and follow-up data through June 5
- Limitations
- Visibility is not visits or revenue, and UK samples do not establish outcomes for Korean sites.
- Start 02:00 — End 06:00 US/PacificCORE Rollout complete
March 2026 core update
Official Google dates · 12d 4h 0m
Limited attribution · Research reviewed
SISTRIX’s UK sector analysis observed net visibility gains for news and losses for informational and education sites.
Scope, limitations and sources
- Observed scope
- UK / sector sample of major rising and falling domains / analysis revised April 14
- Limitations
- Domain-table date labels conflict with the rollout period, so individual percentages are excluded. Earlier spam rollout and background changes complicate attribution.
- Start 12:00 — End 07:30 US/PacificSPAM Rollout complete
March 2026 spam update
Official Google dates · 0d 19h 30m
Limited attribution · Research reviewed
SISTRIX closed its standalone analysis because the short rollout, background volatility and subsequent core update prevented useful isolation.
Scope, limitations and sources
- Observed scope
- UK and US / SERP radar / around March 24–25
- Limitations
- The update-specific effect could not be isolated; that does not establish no impact.
2025
- Start 09:25 — End 11:00 US/PacificCORE Rollout complete
December 2025 core update
Official Google dates · 18d 1h 35m
Observed evidence · Research reviewed
SISTRIX UK visibility for thesaurus.com rose from 228.44 to 283.99 (+24.32%), with gains and losses across informational and commerce sites.
Scope, limitations and sources
- Observed scope
- UK / December 8–29 / SISTRIX Visibility Index
- Limitations
- An individual-domain visibility change, not an average ranking shift or a traffic growth rate.
- Start 09:00 — End 00:00 US/PacificSPAM Rollout complete
August 2025 spam update
Official Google dates · 26d 15h 0m
Limited attribution · Research reviewed
SISTRIX observed low overall SERP change and found hacking, migrations and other confounders among major falling domains.
Scope, limitations and sources
- Observed scope
- UK and US / rollout period / SERP radar and domain cases
- Limitations
- The study did not produce an extensive affected-site list or an update-only loss rate.
- Start 07:30 — End 01:00 US/PacificCORE Rollout complete
June 2025 core update
Official Google dates · 16d 17h 30m
Observed evidence · Research reviewed
SISTRIX’s US radar showed greater movement than March, with later waves affecting different domains.
Scope, limitations and sources
- Observed scope
- US and UK / June 30–July 17 / radar and visibility index
- Limitations
- Results vary by market and sector; timing alone does not establish the cause of a site’s decline.
- Start 09:00 — End 05:35 US/PacificCORE Rollout complete
March 2025 core update
Official Google dates · 13d 20h 35m
Observed evidence · Research reviewed
SISTRIX observed changes from March 16 but relatively low aggregate absolute movement, with few major movers among the top 100 visible domains.
Scope, limitations and sources
- Observed scope
- UK and US / March rollout / radar and selected-domain visibility
- Limitations
- Low aggregate movement does not imply small losses for every individual site.
2024
- Start 09:00 — End 11:00 US/PacificSPAM Rollout complete
December 2024 spam update
Official Google dates · 7d 2h 0m
Limited attribution · Research reviewed
Glenn Gabe examined five cases of search visibility losses alongside scaled content and doorway-page patterns.
Scope, limitations and sources
- Observed scope
- Five selected sites / post-rollout case analysis published January 6, 2025
- Limitations
- Selected cases do not establish an overall impact rate or prove that a content format alone violates policy.
- Start 07:30 — End 11:00 US/PacificCORE Rollout complete
December 2024 core update
Official Google dates · 6d 3h 30m
Observed evidence · Research reviewed
SISTRIX observed larger absolute changes than November, including major health-information movements and mixed retail outcomes.
Scope, limitations and sources
- Observed scope
- UK/US radar and UK domain data / December 12–18
- Limitations
- Interpret the core window separately from the subsequent December spam update.
- Start 11:00 — End 00:00 US/PacificCORE Rollout complete
November 2024 core update
Official Google dates · 23d 13h 0m
Limited attribution · Research reviewed
SISTRIX observed an initial wave around November 15 and later movements overlapping separate site-reputation-abuse actions.
Scope, limitations and sources
- Observed scope
- UK and US / November–December 5 / visibility and directory cases
- Limitations
- Do not combine core-update effects with separate enforcement actions.
- Start 07:58 — End 12:00 US/PacificCORE Rollout complete
August 2024 core update
Official Google dates · 19d 4h 2m
Limited attribution · Research reviewed
SISTRIX observed recovery signs for independent sites such as HouseFresh and large domain movements, alongside a separate ranking bug.
Scope, limitations and sources
- Observed scope
- UK / data from August 15–September 4 / visibility
- Limitations
- Recovery signs are not full recovery; separate bug recovery from core-update effects.
- Start 08:12 — End 09:11 US/PacificSPAM Rollout complete
June 2024 spam update
Official Google dates · 7d 0h 59m
Limited attribution · Research reviewed
SISTRIX radar across five countries showed little movement beyond normal levels; many US falling-domain cases involved 404s, migrations or other causes.
Scope, limitations and sources
- Observed scope
- Five-country radar and US domain sample / June 20–28
- Limitations
- Limited aggregate movement does not establish that spam detection had no effect.
- Start 09:03 — End 07:09 US/PacificSPAM Rollout complete
March 2024 spam update
Official Google dates · 14d 21h 6m
Limited attribution · Research reviewed
SISTRIX UK data showed informational-site losses alongside visibility gains for large platforms.
Scope, limitations and sources
- Observed scope
- UK / overlapping March–April rollouts / domain table is an early-April interim observation
- Limitations
- Effects cannot be separated; the table predates core completion and is not a final loss estimate.
- Start 09:02 — End 10:00 US/PacificCORE Rollout complete
March 2024 core update
Official Google dates · 44d 23h 58m
Limited attribution · Research reviewed
SISTRIX UK data showed informational-site losses alongside visibility gains for large platforms.
Scope, limitations and sources
- Observed scope
- UK / overlapping March–April rollouts / domain table is an early-April interim observation
- Limitations
- Effects cannot be separated; the table predates core completion and is not a final loss estimate.
2023
- Start 12:09 — End 08:30 US/PacificCORE Rollout complete
November 2023 core update
Official Google dates · 25d 21h 21m
Limited attribution · Research reviewed
SISTRIX observed visibility gains for Reddit, Quora and forums, with losses in some news and commerce domains.
Scope, limitations and sources
- Observed scope
- UK / primarily interim observations through November 9–20
- Limitations
- Overlap with the reviews update and interim data prevent a final standalone core-effect estimate.
- Start 09:00 — End 08:00 US/PacificCORE Rollout complete
October 2023 core update
Official Google dates · 13d 23h 0m
Limited attribution · Research reviewed
SISTRIX observed most major SERP movements on October 12–18, with both winning and losing domains.
Scope, limitations and sources
- Observed scope
- UK / overlapping October rollouts / SISTRIX visibility
- Limitations
- Core and spam effects cannot be isolated. Official incident dates take precedence over secondary dates.
- Start 09:51 — End 22:15 US/PacificSPAM Rollout complete
October 2023 spam update
Official Google dates · 15d 12h 24m
Limited attribution · Research reviewed
SISTRIX observed most major SERP movements on October 12–18, with both winning and losing domains.
Scope, limitations and sources
- Observed scope
- UK / overlapping October rollouts / SISTRIX visibility
- Limitations
- Core and spam effects cannot be isolated. Official incident dates take precedence over secondary dates.
- Start 10:30 — End 13:03 US/PacificCORE Rollout complete
August 2023 core update
Official Google dates · 16d 2h 33m
Observed evidence · Research reviewed
SISTRIX reported low overall change but substantial individual-domain movements; its 70-domain news sample had little net change.
Scope, limitations and sources
- Observed scope
- UK / August 22–September 8 / visibility
- Limitations
- A small net change does not mean all sites were stable.
- Start 00:00 — End 07:26 US/PacificCORE Rollout complete
March 2023 core update
Official Google dates · 13d 7h 26m
Limited attribution · Research reviewed
SISTRIX interim data showed gains for UK government sites and mixed reference and news movements.
Scope, limitations and sources
- Observed scope
- UK and US examples / primarily March 17–23 interim data
- Limitations
- Observations predate rollout completion and are not final impact estimates.
2022
- Start 00:00 — End 00:00 US/PacificSPAM Rollout complete
December 2022 link spam update
Official Google dates · 29d 0h 0m
Limited attribution · Research reviewed
Linki’s Czech case study reported one tipli.cz query falling from position 5 to 13.
Scope, limitations and sources
- Observed scope
- Single Czech query / Ahrefs ranking comparison / February 2023 retrospective
- Limitations
- Overlap with a helpful-content update prevents causal isolation or a global impact estimate.
- Start 00:00 — End 00:00 US/PacificSPAM Rollout complete
October 2022 spam update
Official Google dates · 2d 0h 0m
Evidence insufficient · Research reviewed
Official completion is confirmed. This review did not find a usable independent post-rollout ranking study with a clear period, sample and metric.
Scope, limitations and sources
- Observed scope
- Public research and original-measurement searches by update name
- Limitations
- This does not establish no impact or stable rankings. No impact size or affected sector is inferred.
- Start 00:00 — End 00:00 US/PacificCORE Rollout complete
September 2022 core update
Official Google dates · 14d 0h 0m
Limited attribution · Research reviewed
SISTRIX observed UK news-domain losses and cross-country domain movements; a reviews update ended on the same day.
Scope, limitations and sources
- Observed scope
- UK, US and cross-country examples / September 12–27 / visibility
- Limitations
- Overlapping reviews and core updates complicate attribution.
- Start 00:00 — End 00:00 US/PacificCORE Rollout complete
May 2022 core update
Official Google dates · 15d 0h 0m
Observed evidence · Research reviewed
SISTRIX observed major movements in reference, automotive and music sites, with losses among many of 30 news sites examined.
Scope, limitations and sources
- Observed scope
- UK / final May 26–June 9 table and sector cases
- Limitations
- Selected visibility samples do not establish global average rankings or traffic changes.
2021
- Start 00:00 — End 00:00 US/PacificCORE Rollout complete
November 2021 core update
Official Google dates · 13d 0h 0m
Limited attribution · Research reviewed
SISTRIX interim data showed dictionary and reference gains and losses for some social and news domains.
Scope, limitations and sources
- Observed scope
- UK / November 17–25 interim visibility data
- Limitations
- The sample predates November 30 completion and is not a final post-rollout estimate.
- Start 00:00 — End 00:00 US/PacificSPAM Rollout complete
November 2021 spam update
Official Google dates · 8d 1h 0m
Evidence insufficient · Research reviewed
Official completion is confirmed. This review did not find a usable independent post-rollout ranking study with a clear period, sample and metric.
Scope, limitations and sources
- Observed scope
- Public research and original-measurement searches by update name
- Limitations
- This does not establish no impact or stable rankings. No impact size or affected sector is inferred.
How to read the impact research#
Rollout completion and research completion are different. We confirm the official end before reviewing observations. Google recommends waiting at least a full week after a core update completes before comparing Search Console performance with a week before rollout. Google’s core update guidance
Keep rankings, visibility and traffic distinct. Individual keyword positions differ from GSC average position. SISTRIX visibility is a tool-specific measure of search presence, not visits or revenue. Lower GSC impressions alone do not establish lower rankings.
Every number needs a scope. Country, device, sample and comparison windows can change the result. Overseas observations do not establish an identical effect in Korean search. Rollout-only data is labeled as interim evidence.
Timing does not prove causality. Core, spam and reviews updates can overlap with bugs, migrations, hacking or seasonality. A coincident loss is a reason to investigate, not proof of a spam violation. Google’s spam update guidance
Coverage and maintenance#
This timeline covers core, spam and link spam updates since 2021 in the supplied official Ranking history. Discover-only changes, standalone reviews and helpful-content updates, and general outages are excluded; overlapping changes may be discussed as confounders.
All rollout times use the source’s US/Pacific timezone with date-specific daylight saving offsets. Historical midnight timestamps are retained as supplied; they do not imply additional minute-level precision.
Every 15 days, we check both official notices and post-rollout impact research. New launches, completion notices, corrections and substantive new research are incorporated. Insufficient evidence does not mean no impact; new usable research can fill those gaps.
Only substantive content changes update lastmod. Korean and English versions are published together; unchanged checks leave the modification date alone. Records are retained even if removed from the source.
Reporting anomalies are tracked separately in the Search Console data issue timeline .
