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Research Guides

Searching for Patents by Keyword(s)

WARNING!

  • No controlled vocabulary in patents

  • Patents have the aspects of both a technical and a legal document

USPTO Patent Public Search

  • Ability to search full-text with keywords from 1970 to the present
  • OCR scanned pre-1970

Databases

Patent Search Databases (open access):

  • United States Patent & Trademark Office (USPTO)

    • Patent Public Search (PPUB)
      • US-PGPUB (U.S. pre-grant applications March 2001-present)
      • USPAT (Full-text U.S. patents 1970-present, classification and patent number searching 1790-present)
      • USOCR (OCR scanned pre-1970 U.S. patents)
    • USPTO Search for Patents Portal (Starting point for all types of searches, USPTO search systems and databases)
       

  • Google Patents
    Indexes full-text patent documents from the US, European Patent Office, Canada, China, Germany, and WIPO.

  • Patent Lens

  • European Patent Office (EPO):  Espacenet
    Covers millions of patent documents from more than 90+ countries including the United States. Database of the European Patent Office (EPO)

Database with Patent Content (UW Subscription):

Additional USPTO Resources & Databases

Patent Center
The U.S. Patent & Trademark Office Patent Center system is a tool for electronic filing and management of patent applications. Public users, applicants, and patent owners can track status, maintenance fees, and file history information for United States patents. PDF images of some documents included. Online ordering of patent documents is available.

Search Published Sequences:  Publication Site for Issued and Published Sequences (PSIPS). Issued and published sequences, tables and other mega items.

Patent Assignment Search:  Ownership information/Changes in ownership.

Main Patent Portal @ USPTO

Official Gazette for Patents (OG)

 

Outline: Searching for Patents by Subject

  • As far back in time as necessary

    • Cannot re-patent an identical invention

  • CPC Classifications (Schemes/Schedules & Classification Symbols) / US Classifications and Subclassifications (USPC)

    • Also known as classes and subclasses in USPC (some continue to use this terminology in CPC)

    • CPC = Cooperative Patent Classification / USPC = US Patent Classification

  • Brainstorm terms - consider synonyms.  Use these terms to locate CPC schemes and classification symbols.  Use these terms to locate USPC classes and subclasses if needed.

  • Multi-Step U.S. Patent Search Strategy
    PatFT, AppFT, PubEAST and PubWEST were retired on September 30, 2022. The new Patent Public Search (PPUB) is now available via the USPTO website.  Please note, some of the USPTO search guides, including the "Seven Step Strategy" still refer to PatFT, AppFT, and the other databases.  Use Patent Public Search.

  • Browse CPC Classifications (USPTO) / CPC Search and Browse by CPC Section (EPO)

  • Search classification schemes by keywords or look up particular CPC symbols on the USPTO Classification Resources page.

  • USPTO Patent Public Search:  search by classification (CPC symbols and USPC classifications) 1790 - present

    • CPC used for new Utility patent documents (2015-).  USPC still used to classify Design and Plant patent documents.

  • Examples of other search types:  Inventor (Patentee), Assignee (Owner), Issue Date, Attorney

  • Interpret results via patent titles, abstracts, full-text (process of elimination)

  • In a patentability search, people are hoping NOT to find something.  Searching for the absence of something?

    Resources:

UW Engineering Library Patent Searching Guide

Search for patents - USPTO portal

Multi-Step U.S. Patent Search Strategy - Conducting a preliminary patent search (USPTO Detailed Handout - Long version)

USPTO Online Tutorial - includes Patent Public Search (38 minutes): "How to Conduct a Preliminary U.S. Patent Search: A Step by Step Strategy " 

USPTO Patent Public Search (PPUB):

Patent Classification Page (USPTO)

Index to the United States Patent Classification (USPC)

Cooperative Patent Classification (CPC)

New patent classification system replaced US patent classification. On January 1, 2013, the USPTO transitioned from using the United States Patent Classification (USPC) system to the Cooperative Patent Classification (CPC) system. The CPC has been adopted by many countries.

"The Cooperative Patent Classification (CPC) effort is a joint partnership between the United States Patent and Trademark Office (USPTO) and the European Patent Office (EPO) where the Offices have agreed to harmonize their existing classification systems (European Classification (ECLA) and United States Patent Classification (USPC) respectively) and migrate towards a common classification scheme."

USPTO and EPO informational site: CPC - Cooperative Patent Classification