Guide to finding patents, based on the collections of the State Library of Victoria

US patents 1790 onwards

Finding United States patents

Are you searching for a patent registered in the United States ?

Do you know?

  • number of patent
  • date of patent
  • name of inventor
  • nature of invention

If you know these details contact staff  who can order the relevant patent from our offsite store. You can view or copy the patent in the Library. When ordering this item, the Library staff will need to include the patent number and the date (it is optional to include patent title and patentee's name).

If you do not have these details you will need to search the relevant indexes (see US Patent Indexes box on this page). Indexes are held onsite and offsite. Contact staff to order offsite indexes. To initially refine your search, refer to the Finding patents page in this guide.

US patents and patent journals

Types of US patents

Utility Patent or Patents for Invention
Design Patent
Plant Patent
Reissue Patent
Defensive Publication
Statutory Invention Registration (SIR)

Full descriptions of each type of US Patent as published by the USPTO

US patents - SLV print holdings

•          Printed Patents - Not held

•          Microfilm - United States Patents - 1920 to 1996 - YA 608UN3P - held offsite at Ballarat Store


US Patent Journals - SLV print holdings

•          Official Gazette of the United States Patent Office - 1872 to 1901 + 1923 to 1985 - YA 608 UN3G - contains Names of applicants and brief abstracts

US patent journals - online editions

•          Official Gazette of the United States Patent Office, 1899-2002 (Hathi Trust Digital Library) - contains Names of applicants and brief abstracts

US patent indexes

Name & subject indexes - print

•          Index of patents issued from the United States Patent (and Trademark) Office - 1927 to 1973 + 1974 to 1986 - YA 698 UN3IP - includes name Indexes & Subject Indexes - (title varies)

•          Official Gazette of the United States Patent Office - 1872 to 1901 + 1923 to 1985 - YA 608 UN3G - (title varies) - includes Name Indexes & Subject Indexes

•          Annual report of Commissioner of Patents - 1843 to 1965 (incomplete) - YA 608 UN3A - title varies - includes Name and Subject (title keyword) Indexes

Name & subject indexes - online

•          Indexes from the 'Annual report of Commissioner of Patents' and the 'Index of patents issued from the United States Patent Office' - 1842 to 1958 (incomplete) - (Hathi Trust Digital Library) - includes Name and Subject (title keyword) Indexes

Subject indexes - print

•          Subject-matter index of patents for inventions issued by the United States Patent Office from 1790 to 1873, inclusive (1976) - 3 volumes - R 608 UN3S

Frequency hopping technology invention by Hedy LaMarr, actress/inventor.

Hedy LaMarr (1914-2000), actrress and inventor, in 1944. Photo: By Employee(s) of MGM (source) [Public domain], via Wikimedia Commons.

The famous American actress of the 1940s, Hedy LaMarr, was also an inventor, although she had no formal training or technical qualifications. 

During World War II  she came up with  the concept of frequency hopping as a solution to the problem of the enemy jamming radio signals used in the remote control of  torpedoes.

The patent was registered by the United States Patent Office on August 11, 1942 under LaMarr's real name, Hedy Kiesler Markey. United States patent number 2,292,387. 

The concept was rejected by the US Navy, but after the war the patent  was rediscovered and the technology  was used in communications technology during the Cuban Missile Crisis of  1962.  It is used in wireless technology today.

The patent is on  the US patents website under the title  Secret Communication System. Hedy LaMarr  registered the patent under the name Hedy Kiesler Markey with her colleague Geoge Antheil. 

There is information about the invention in a blog LaMarr's daughter wrote:  A Movie Star, Some Player Pianos, and Torpedoes

Online resources

Searching for U.S. patents online. 

Search for United States patents on the website of the USPTO (United States Patent and Trademark Office) 

Pre-1976 patent searches are limited to patent numbers and classification codes. 

Database searches: 

1790 to 1975 - Images of patent applications with specifications and diagrams. Searchable only by Issue Date, Patent Number, and Current US Classification

Example:  Patent number 1935 from January 20, 1841. Lifeboat. Inventor: S.C. Batchelor.

From 1976 onwards, you can search using  Quick search, Advanced search and patent number.

2001 onwards: Search the full text and image database. 

Google Patents.

Search for patents from 1790 onwards. 

Use the Advanced Search option  Search by keyword, date, inventor. Google Patents has invention descriptions and digitised diagrams.

Free patent search tool: PDF files of US patents 

Search by US patent number. It displays the full text and diagrams of all US patents.  

Examples: Nikola Tesla patent "Apparatus for transmitting electrical energy." Application filed January 18, 1902. Renewed May 4, 1907. Patented December 1, 1914. Patent number 1119732.

Alan A. Ford patent number 5,123,471, June 23, 1992. Adjustable vertical vane hanger. 


US patent numbers

Date and Number table of US patents

US Patents from 1790 to 1836 were issued by name and date, bur no number was allocated. The current system of numbering US patents began on 13 July 1836.

Famous American inventors

The patent numbers of inventions of famous American inventors may be listed on the Internet. Try a Google search using terms such as the name of the inventor and the word patents. 

For example, the titles and patent numbers for many of Nikola Tesla's inventions are listed on Wikipedia  The site also includes the patent numbers for his patent applications lodged in Britain, Canada, France and Spain. 

The American patents have the patent number and a direct link to the  Google Patents web page featuring the patent.

Nikola Tesla

Nikola Tesla  (1856-1943) was  the inventor of the first machine to effectively use Alternating Current (AC) electricity, the system of electricity used widely in machines today. 

Tesla also developed wireless telegraphy (ahead of Guglielmo Marconi), fluorescent lights, a remote control boat, and much more.

You can find digitised images of  many of Tesla's inventions on the Google Patents website