Skip to Main Content

Patents and Trademarks

Patent & Trademark basic information, databases, links for legal and status information

Database search tips



Patent Classification:  

Searching patents by classification codes is very important. There is no standard terminology to describe patents, because words change as technology changes. Subject classification helps group related technologies under one class or subclass code. To search for subject classes, the European Patent Office has a  Cooperative Patent Classification (CPC)  search page that looks for words in patents, and ranks the most likely 8 -10 CPC subclasses that those patents are under. To search for CPC definitions ONLY, use site search box:  "cpc scheme" [word/s]

Quick searches:

Google Patents

  •  Familiar Google search; defaults to relevance ranking, phrases in quotes; VERY fast
  • Granted patents and pre-grant applications in one search; 120+ million records (worldwide)
  • Classification links to European Patent Office Cooperative Classification (CPC)  index search
  • The only current FREE search for pre 1970 text - but its OCR has errors 
  • Download CSV results to Excel
  • Use for field, Boolean, proximity search
  • See "About Google Patents" for detailed instructions, coverage, documentation, etc


  • Proprietary search engine - no way to know exactly what their algorithms look for
  • Google is under no obligation to provide a free search

  • One of the largest international databases: “over 110 million patents from 90 offices worldwide" as of April 2020
  • Includes most US patents (about 1/6 of the world’s total)
  • Search by titles back to 1920 for major offices
  • Search by International Patent Classification (IPC) and Cooperative Patent Classification (CPC) back to the 1800s (1836 for US)
  • Display defaults to 25/page; “compact” shows 50 Patent nos./titles; click “load more results for export”
  • Set full record display for up to 3 frames - title list, image, choice of bib record/claims/abstract, etc.
  • Export includes numbers, titles, applicants (assignees), IPC and CPC classifications
  • Up to 500 pages; sort up to 500 records (see “limitations” in Help index)
  • Proximity search of EPO and WIPO patents: mouse prox/distance<3 trap


  • PDF navigation can be a bit slow and cumbersome
  • No full text search except EPO and WIPO databases

  • Google-like simple search; advanced search; “Field Combination” shows 45 fields
  • Rapidly growing database: 97 million records as of July 2021
  • Proximity search: “electric car”~10 or electric NEAR car (same as “electric car”~5)
  • Includes US patents back to 1836 – many searchable titles
  • “Cross Lingual Expansion” search adds hundreds of words in other languages to your search
  • Chemical search includes InChI Keys and structure search/display (with free account)
  • Create account to download up to 10,000 records, save customized configuration and queries

·         Best to compare results in Google Patents and Espacenet - all 3 have different ways of entering records (one of the very largest databases – “121* million patent documents” as of April 2020)

  • Graphs to help visualize output, and make selections of data
  • Search all offices, or choose from list
  • Register a free account to save collections, up to 100,000 documents


  • Many fewer search fields: Inventors, Owners (US), Title, Abstract, Claims, Applicants, Non Patent Citations, Publication and Filing Number and date
  • Seems to have limited word/name search before about 1900; SOME US titles back to @ 1836

  • Can find US granted patents and pre-grant publications in one fast search
  • Advanced Search can also include EPO and PCT patents, Japan patent abstracts and Non-Patent Lit
  • Same field search as patft and, and usually faster
  • Allows proximity search: aclm/”biomass gasification”~5
  • Free account lets you download up to 1000 records per search and export to Excel


  • search words and names only back to about 1970s
  • PDFs can be tricky to load and navigate and

  • Detailed field search:  claims, address broken down by city and state, primary and secondary examiner… (See full chart in Advanced Search)
  • Quick navigation within VERY large lists of results -even in the 100s of thousands ("Jump to" distant record numbers)
  • Compact display of 50 titles/page
  • US Patent Classification search back to 1790; CPC being added and already covers many 1800s patents


  • separate search for granted patents and pre-grant published applications
  • slow navigation from list to full text and back
  • sometimes USPTO server is very slow even for searches
  • Use right mouse button to open image in new window – only way to return to list quickly
  • No proximity search – can only do phrases in quotes or Boolean AND, OR, and NOT

For more sites: click “Other International Pat/TM databases” in this guide

Legal and status information:

·        Public PAIR:

  • Since about 2003, “Image File Wrapper” has record of all legal proceedings
  • “Image File Wrapper” and “Transaction History” often have different information
  • “Non-Patent Literature” usually is journal or conference article; VERY seldom is online

Global Dossier (USPTO search site - Espacenet links from its patent records seem to work better as of 12/2017)

·        Current owners:

.   But owners are NOT required to report changes to USPTO

  • results link to Global Dossier, patent family and INPADOC status
  • Mainly legal status, but sometimes includes change of owner information

Bulk Downloads: