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Patents Online: Basics for Researchers: Reading a U.S. Patent

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Reading a U.S. Patent

The outline of a patent is similar to a research article (author, title, etc.), it is also different. The first page of a patent contains its basic information including the abstract. References cited act as a bibliography. This is followed by any applicable drawings. The Background and Summary of the Invention in the body of the patent contains a detailed description of the invention. The Claims define its scope. 

Patent Number

Patents are numbered as they are issued. Patents are not included as full-text in traditional literature, so locating the full-text via another website is necessary. See Finding the Full-Text of Patents to locate the full-text of the patent with just the patent number. For most countries, the patent number is in the upper right corner of the patent.

A letter or number that follows a patent number indicates a Kind Code (e.g., publication of an application for a utility patent, “used to distinguish the kind of patent document and the level of publication.”) This is a World Intellectual Property Organization Standard. A table of codes is available via the USPTO website.

Issue Date

In the U.S., the date the patent was issued is in the upper right corner below the number. See line 22 in the left columm to see when the patent was filed. Two years is common for a patent to issue from date of file.

Title, Inventors and Assignee

The title of the patent is at the top of the left column. The inventor(s) follow, and then the assignee or owner if applicable. If both are present, it is assumed that the inventors are employed by the assignee/company.

Abstract and Body

The abstract is the concise summary of the patent. Within the body, the Background and Summary of the Invention contains a detailed description of the invention. The Claims define its scope.

References Cited (U.S. Patent Documents and Other Publications)

The references cited are those patents and or articles etc. listed on the first pages of the patent that are similar or related in some way as prior art. These are most useful for searching related patents, but they can also be a very rich source for traditional literature, articles, etc.

U.S. Classification

Located at line 52, this is the area of focus when doing a comprehensive preliminary patent search for related patents or in this subject area. The USPTO has a system of 470 subject categories to organize patents by how they work. (See 4 following.)

International Classification

Located at Line 51, this is the letter/number combination to use when working to identify similar foreign or international patents. See Searching Patents below.

How to Read a U.S. Patent