Google's patent

On February 26, 2003 an article, written by Stefanie Olsen, appeared on the CNet news site entitled Google lands Web search patent.

In this article Stefani Olsen provides details of Google's search strategies.

Firstly, Stefanie Olsen describes the patent, which Google filed on Jan. 30, 2001, and was granted February 26th 2003, which "governs methodology for parsing through Web documents to deliver Web surfers the most relevant pages for their queries". Olsen tells us that "it deals with 'an improved search engine that refines a document's relevance score based on interconnectivity of the document within a set of relevant documents' (according to a summary of the patent)".

The summary description of the patent is:

Methods and apparatus for using a modified index to provide search results in response to an ambiguous search query


A system allows a user to submit an ambiguous search query and to receive potentially disambiguated search results. In one implementation, a search engine's conventional alphanumeric index is translated into a second index that is ambiguated in the same manner as which the user's input is ambiguated. The user's ambiguous search query is compared to this ambiguated index, and the corresponding documents are provided to the user as search results.

In descibing the patent, Stefanie Olsen writes:

The new patent deals with the process for finding matching documents. Under the methodology, Google turns up an initial set of documents related to the keyword and then ranks each page with a "relevance score." Next, it calculates a "local score value" that quantifies "an amount that the documents are referenced by other documents in the generated set of documents," according to the filing. Finally, the local score values influence the relevance ranking of a page.

According to the patent, "a search engine modifies the relevance rankings for a set of documents based on the interconnectivity of the documents in the set. A document with a high interconnectivity with other documents in the initial set of relevant documents indicates that the document has 'support' in the set, and the document's new ranking will increase. In this manner, the search engine re-ranks the initial set of ranked documents to thereby refine the initial rankings."

Stefanie Olsen informed us also:

The company now has three outstanding patent applications. Two concern methods and technology for providing search results in response to an ambiguous search query. The third deals with methodology and technology for delivering search results that use analysis of Web page usage.

In addition, Google co-founder Larry Page invented a methodology called PageRank, which was patented to the board of trustees of the Leland Stanford Junior University on September 2001. PageRank is one of Google's recipes for calculating the popularity and relevance of Web pages based on the number of other pages linking to it.