Around September 10th, Google made an unannounced update that affected how search results can be requested from various SEO measurement platforms. This change means that platforms such SEMRush, Ahrefs, or Brightlocal may show fewer results than usual, and in many cases, only 10 instead of the standard 50-100.

What we know so far:

Removal of &num=100 Parameter:

One of the major items agencies are reporting is that Google appears to have removed or disabled the use of the &num=100 parameter for SERP (Search Engine Results Page) queries. This parameter used to allow tools to request up to 100 search results in a single query.

Without it, many tracking tools are now only able to request fewer results per query, or they have to split requests across multiple pages (pagination) to get to 100 results. This increases request volume, slows data retrieval, and makes reporting more complex and less reliable.

Drops in Keyword Ranking Visibility / “Ranking Drops” in Tools:

Because of that parameter change, many rank-tracking tools are showing large drops or missing data in terms of keyword positions — especially for keywords for which the site was appearing beyond the top ~10 or 20 results.

Impression Drops in Google Search Console (GSC):

Some sites are also observing drops in “impressions” in GSC around the same period. The theory is that if rank-tracking tools can’t see past a certain number of positions, or if Google is limiting how many results are reported for certain queries (or how they are counted), this could indirectly affect what Google counts/shows in impressions.

What to Expect:

While measurement platforms rush to update the way they request search results from Google, we can expect much instability and decreased results. How well these platforms are able to adjust and get data in the long term is yet to be determined.

What this means:

• Reporting looks different, not your traffic.
  Many sites are seeing impressions drop and average position improve—but that’s because inflated “deep results” data has been cut out.

• Rank trackers are disrupted.
  Tools now need ~10× more requests to fetch the same depth of SERP data. Some are truncating beyond position 20 into “20+” buckets.

• Historical comparisons get tricky.
  Pre-change vs. post-change data won’t line up cleanly.

How to adapt:

• Don’t panic over impression drops—this is a data artifact, not lost traffic.
• Re-establish new reporting baselines (post-Sept 2025).
• Focus on top 10–20 rankings
• Annotate this change in dashboards so stakeholders know why metrics shifted.
• Ask your SEO reporting providers how they’re handling deeper rank data.
• Remember, Google Analytics will still reliably show how many visitors came to your website, where they came from, and what they did when they got there.

The takeaway: This is a measurement change, not a performance change. True SEO success is still about driving real clicks, conversions, and authority—not just chasing deep rankings.