PatentBrief

How Websites Get Ranked by Who Links to Them

This patent describes a computer method for scoring web pages or other linked documents based on the importance of the pages that link to them, helping search engines find better results.

Granted 2001activeExpired 2018Owned by Leland Stanford Junior UniversityInvented by Lawrence Page

Original patent title: “Method for node ranking in a linked database

What this patent covers

The actual claim

The patent describes a computer method for scoring documents in a linked database, such as the World Wide Web. It starts by "obtaining a plurality of documents" (Claim 1). Then, it "assigns a score to each of the linked documents based on scores of the one or more linking documents" (Claim 1). This means if an important page links to your page, your page gets a higher score. The method can use various "weighting factors" for these linking documents, such as the number of links they have (Claim 2), how likely they are to be accessed (Claim 3), or even user preferences (Claim 7). Finally, it involves "processing the linked documents according to their scores" (Claim 1), which could mean ordering them in search results. For example, if a popular news site links to a small blog, the blog's score would increase because of the news site's high score.

What this patent does NOT cover

The boundaries

  • Does not cover ranking documents solely based on their content keywords without considering incoming links.
  • Does not cover ranking systems that only count the number of incoming links without considering the quality or score of those linking documents.
  • Does not cover ranking documents where the score is determined only by user clicks on the document itself, rather than the linking documents.
  • Does not cover ranking systems that manually assign scores to documents without a computer-implemented method.

These exclusions are unique to PatentBrief — derived from the actual claim language, not patent-office boilerplate.

What made this novel

The truly novel idea was to treat links as "votes" of importance, where a link from a more important page counts more than a link from a less important page. This recursive definition of importance, combined with the "random surfer" model (Claim 10's "random traversal"), allowed for an objective and scalable way to rank the vast and ever-changing web.

Method for node ranking in a l…(Primary claim)softwaretelecommunicationsai mlecommerce

Schematic visualization of the patent's claim structure. Hand-drawn diagrams in progress for each landmark patent.

Where you've seen this

Real-world examples

01

Google Search (PageRank algorithm)

02

Academic citation indexing (e.g., impact factor calculations)

03

Social network influence scoring

04

Web crawling and indexing systems

Why it matters

The bigger picture

This patent is foundational to how modern search engines, particularly Google, determine the relevance and authority of web pages. The core idea, known as PageRank, was developed by Larry Page and Sergey Brin at Stanford. It dramatically improved search results by moving beyond simple keyword matching to evaluate the entire link structure of the web. This method helped Google become the dominant search engine by providing more useful and relevant results.

Filed

January 9, 1998

Granted

September 4, 2001

Claim 1 — Plain English

What this patent covers

The patent describes a computer method for scoring documents in a linked database, such as the World Wide Web. It starts by "obtaining a plurality of documents" (Claim 1). Then, it "assigns a score to each of the linked documents based on scores of the one or more linking documents" (Claim 1). This means if an important page links to your page, your page gets a higher score. The method can use various "weighting factors" for these linking documents, such as the number of links they have (Claim 2), how likely they are to be accessed (Claim 3), or even user preferences (Claim 7). Finally, it involves "processing the linked documents according to their scores" (Claim 1), which could mean ordering them in search results. For example, if a popular news site links to a small blog, the blog's score would increase because of the news site's high score.

The clever bit

The truly novel idea was to treat links as "votes" of importance, where a link from a more important page counts more than a link from a less important page. This recursive definition of importance, combined with the "random surfer" model (Claim 10's "random traversal"), allowed for an objective and scalable way to rank the vast and ever-changing web.

What it does not cover

  • Does not cover ranking documents solely based on their content keywords without considering incoming links.
  • Does not cover ranking systems that only count the number of incoming links without considering the quality or score of those linking documents.
  • Does not cover ranking documents where the score is determined only by user clicks on the document itself, rather than the linking documents.
  • Does not cover ranking systems that manually assign scores to documents without a computer-implemented method.

Patent Journey

From filing to expiry

Patent Filed

1998

Patent Granted

2001 · 4yr after filing

Highly Cited

817 patents cite this

Patent Expired

2018

PatentBrief Score

Impact Score

60/ 100

Strong

Citation count

40/40

Highly cited

Claim breadth

20/20

Very broad protection

Recency

0/20

Older than 20 years

Assignee scale

0/20

Independent or smaller assignee

PatentBrief Impact Score — based on citation count, claim breadth, recency, and assignee scale. Not a legal assessment.

The original legal language

Original claims

35 claims as filed with the patent office.

Citations

Patent lineage

Cites earlier patents

7

earlier patents this invention cites as foundations

View prior art →

Cited by later patents

817

later patents that build on this invention

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Last reviewed: May 25, 2026 · PatentBrief is not a law firm and this is not legal advice.