Did you know Google has a technology called FastSearch? No, not the one from the early 2000s, but its own Google FastSearch. Google said FastSearch is faster than Google Search, its main search results technology.
FastSearch is used by Gemini for grounding purposes, to validate the Gemini responses. It is faster than Google Search because it retrieves fewer documents than normal Google Search. Yes, this can result in lower quality than Google Search's fully ranked web results but it is good enough for grounding.
This was spotted by Marie Haynes who posted about this on X after reviewing the Judge's decision on the remedy rulings for Google's monopoly case.
The document says:
To ground its Gemini models, Google uses a proprietary technology called FastSearch. FastSearch is based on RankEmbed signals — a set of search ranking signals-and generates abbreviated, ranked web results that a model can use to produce a grounded response. FastSearch delivers results more quickly than Search because it retrieves fewer documents, but the resulting quality is lower than Search's fully ranked web results.Google does not make FastSearch directly available to third parties through an API. Rather, the technology is integrated into a Google Cloud offering called Vertex AI, which is available to third parties to ground on Google Search results or other data sources. Vertex customers do not, however, receive the FastSearch-ranked web results themselves, only the information from those results. Google limits Vertex in this manner to protect its intellectual property.
This is on page 35 of the ruling PDF:
Here is Marie's post:
— Marie Haynes (@Marie_Haynes) September 3, 2025
Forum discussion at X.
