Google started rolling out the September 2026 spam update on September 24, and this one breaks the pattern that made previous spam updates easy to diagnose. Google says the rollout may take up to two weeks to finish — a stark contrast to the previous three spam updates of 2026, which each completed in under three days. The update applies worldwide and in all languages. It is Google's fourth spam update of the year.

Google has not said what this update targets.

When Search Engine Roundtable's Barry Schwartz asked whether the two-week estimate was a typo, given how fast recent spam updates finished, Google's John Mueller replied on Bluesky that the rollout is "likely to take longer than some of the previous ones." That is a confirmed Google statement: the length is intentional, not a mistake.

Ranking volatility started before the announcement

Search Engine Roundtable reported ranking volatility starting around September 23 — the day before Google's announcement. That timing matters for attribution. Rankings were already moving before Google confirmed anything, and a two-week rollout will overlap with whatever else shifts in search during that period.

The practical consequence: the tight diagnostic window marketers relied on for the previous three spam updates is gone. Instead of comparing rankings across a two-to-three-day flip, anyone investigating a drop now faces up to two weeks of gradually shifting results, layered on top of normal volatility.

Until Google marks the rollout complete on the Search Status Dashboard, treat the entire period as a watch window rather than a measurement point.

The site reputation abuse question

This is the first spam update since Google changed its site reputation abuse policy on August 28. Google has not linked the two, and no confirmed statement suggests the update enforces that policy change. Any connection between the August 28 policy revision and this update remains speculation until Google says otherwise.

For sites that do see changes, Google's spam update documentation recommends reviewing its spam policies. Google adds that making changes may help if its automated systems learn, over a period of months, that the site complies. Recovery, in other words, is not immediate even after fixes.

How to separate spam-update impact from other causes

A longer rollout makes attribution harder, but a structured check can still narrow down what happened. The goal is to establish when visibility changed, who else moved, and where.

Establish the timing. Daily position tracking of target keywords gives a dated record. Compare rankings from before September 23 with the days after September 24 — and keep comparing through the rest of the rollout, not just the first few days. A drop that begins mid-rollout is harder to pin down than one that starts with a clear before-and-after break.

Check whether competitors moved too. Competitor visibility data over the same period answers the most basic attribution question. If an entire competitive set moved together, the change probably reflects the update or another broad system shift rather than a site-specific problem. If only one site moved while rivals held steady, the cause likely sits on that site's own pages.

Look outside Google. Tracking citations across ChatGPT, Google AI Mode, Gemini, and Perplexity in a single dashboard provides a control group. If Google rankings dropped but citations in ChatGPT and Perplexity held steady, the cause is probably specific to Google — consistent with a Google-side update. If visibility fell across every surface at once, look instead at something site-level, such as content or technical changes.

Measure overall SERP volatility. Daily SERP movement tracked by category shows whether volatility is hitting search results broadly or concentrated in specific verticals. Category-level spikes during the rollout window help distinguish an update effect from isolated ranking noise.

What to monitor

The rollout should run through roughly October 8 if Google's two-week estimate holds — and Mueller's comment suggests it could run longer. Watch the Search Status Dashboard for the official completion marker, track category-level volatility through Semrush Sensor as the update progresses, and re-check competitor movement before attributing any drop to this update.