The Digital Marketing Search Reset: How Google’s Quiet Technical Change Shook SEO Data—And How Hong Kong Businesses Can Adapt to GEO & AI

The Seismic Shift in Digital Marketing Search

For years, Search Engine Optimisation (SEO) professionals have relied on structured, comprehensive data to measure performance. However, in September 2025, the foundation of this measurement was significantly undermined when Google quietly deprecated the &num=100 parameter. This small, technical tweak has triggered widespread disruption across the digital marketing search ecosystem, leading to sudden drops in reported impressions and keyword visibility across major rank tracking tools and even Google Search Console (GSC). If your organic traffic appears to be “disappearing,” or your SEO dashboards are “acting up lately,” you are not alone. This change is fundamentally reshaping how performance is measured, demanding that SEOs transition from focusing purely on “rankability” to optimising for “retrievability” within the new, AI-driven search landscape.

The Technical Shockwave: Understanding the num=100 Removal

Historically, appending &num=100 to a Google search URL allowed users and—crucially—SEO tools and scraping bots to retrieve up to 100 organic search results on a single Search Engine Results Page (SERP). This functionality was vital for comprehensive rank tracking, allowing tools to efficiently check site rankings far beyond the first page.

However, Google’s removal of this long-standing feature means the search giant now limits the retrievable results, often capping SERP visibility from an analytics perspective to the top 20, or sometimes even fewer results.

The data fallout has been immediate and dramatic, providing stark numbers that illustrate the severity of the shift:

• Impressions Decline: An analysis of 319 properties found that 87.7% of sites experienced a decline in impressions reported in Google Search Console.
• Keyword Visibility Loss: A staggering 77% of sites lost keyword visibility after the removal.
• Unique Ranking Terms: 77.6% of sites lost unique ranking terms.

This removal has been observed to particularly impact short-tail and mid-tail keywords, while fewer queries now show on page 3 or beyond.

The Costly Aftermath: Broken Tools and Financial Repercussions

The &num=100 parameter was the cornerstone of efficiency for rank-tracking software. Without it, the mechanics of data gathering have fundamentally changed, resulting in a 10x increase in crawl load for tool vendors.

Before the change, the calculation for data retrieval looked like this: 1 request = 100 results. Now, to obtain the same 100 results, it requires 10 requests. This shift has profound financial consequences, as tool providers face significantly increased infrastructure costs. Companies like AccuRanker have already adapted by changing their default tracking depth, often only tracking the top 20 results, citing that retrieving more results significantly increases costs. These rising operational burdens are likely to be passed on to customers through subscription price hikes.

GSC Data Distortion: The Great Decoupling Unravelled

Beyond third-party tools, the change immediately impacted first-party data within Google Search Console (GSC). Many website owners noted a significant decline in desktop impressions accompanied by a sharp increase in average position around mid-September.

The leading theory posits that the drop exposes the degree to which impressions were being generated by analytical bots. When a rank-tracking bot loaded a page of 100 results using the parameter, a site ranking at position #99 would register an impression in GSC, even if a human user never scrolled that far. With the parameter gone, these bots can no longer generate impressions for positions 11-100 on a single page load.

While this means reports may look “weaker,” it suggests that the GSC data is now actually more accurate, reflecting actual user views without the distortion caused by the influx of scraper impressions. This new evidence suggests that the previous trend known as “The Great Decoupling”—where GSC impressions rose without matching clicks—may have been heavily “polluted” by bot activity.

Google’s Strategy: Streamlining Data and Combating Competition

Google has confirmed that the use of this URL parameter is not something they formally support, clarifying that this does not appear to be a bug but an intentional change. While Google did not explicitly state the reasons, SEO experts point to several likely motivations:

1. Limiting Scraping: Making automated data extraction more difficult and costly for third parties.
2. Protecting Infrastructure: Reducing server strain from heavy, large-scale requests.
3. Combating AI Competition: Some experts believe this is a defensive move against competing Large Language Models (LLMs) like OpenAI’s products, which scrape Google’s index to ground their results. As one analyst suggested, “the index is the prize,” and Google is working to protect its valuable data asset.

The Future of SEO and Digital Marketing Search: Pivot to Relevance and GEO

In this new search landscape, where visibility is capped and traditional ranking data is less reliable, the strategic focus for digital marketing search must change. SEO is not broken, but it is fundamentally different. We must adapt accordingly.

The priority shifts from chasing precision on page 4 rankings to optimising for relevance and Generative Engine Optimisation (GEO).

The core message remains: Visibility is capped, but relevance is not. By writing with intent, optimising for retrievability, and measuring what truly matters, businesses in the competitive Hong Kong market can stay agile as the search ecosystem continues to evolve.