Patent Search Tutorial - 2019

This tutorial will help you to understand patents and the process of searching for patents. In order to ensure that your search will return the best results, this tutorial reviews a number of different techniques.

Throughout this tutorial there will be short videos demonstrating how to use the United States Patent and Trademark website. You may also want to supplement this information with books related to searching for patents or contacting the Patent and Trademark Resource Center librarian, John Meier, or your local Penn State library.

Patent and Trademark Resource Center Logo.

Penn State University Libraries maintain Patent and Trademark Resource Center (PTRC) in the Physical and Mathematical Sciences (PAMS) Library. As an official depository of the United States Patent and Trademark Office (USPTO), we have a formal agreement to provide assistance to the public in the use of patent and trademark resources provided by the PTO. Librarians and library staff are familiar with search resources and can show you how to use computerized databases, collections, and other resources for searching.

What is a Patent?

A patent is an official document securing to an inventor for a term of years the exclusive right to make, use, or sell an invention. The U.S. Patent and Trademark Office grants, on behalf of the Federal government, utility patents, design patents and plant patents. No other agency or jurisdiction can grant patents in the United States.

A patent is similar to a real estate title in two ways. First, it confers ownership of the invention. Second, it describes the invention in very precise terms. These terms are referred to as "claims".

The exclusive right of a patent is the right to stop others from making, using or selling your invention, but a patent does not give you the right to make, use or sell your invention.

Illuminated Football

Illuminated Football (US Patent 5,490,047)

What Can Be Patented?

Since patents are official documents issued by the Federal government, certain criteria must be met when officials are establishing whether a product or invention is suitable for patentability. Federal law has established three specific criteria used by the Patent and Trademark Office to determine whether an invention, as described in the patent application, is patentable. In addition to the subject matter criteria, in other words, the description of the invention, formal elements of the application must also be in good order. An incomplete application will not yield very good results.

Because the patent document is an official record that provides detailed information about specific inventions, inventors are required to make a full disclosure of the invention so that someone who is skilled in the technological area of the invention can reproduce the invention by using the information contained in the patent.

The three criteria include:

  • Utility: Does the subject matter have a useful purpose? This includes "operativeness;" in other words, a machine that will not operate to perform the intended purpose would not be called useful, and therefore would not be granted a patent.
  • Novelty:The invention must be new.
  • Non-Obvious: Non-obvious requires that the difference between "existing art" and the invention be significant enough to warrant a patent.

Types of Patents

There are three different types of patents for which an inventor may apply:

Utility Patent example picture.

Utility Patent is issued for a new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof.

My Little Poney Design Patent example image.

Design patents are issued to any person who has invented any new and non-obvious ornamental design for an article of manufacture.

Image of apples as an example of a plant patent.

As its name implies, a plant patent is issued to anyone who has invented or discovered and asexually reproduced any distinct and new variety of plant

Parts of a Patent

Patents are somewhat complex documents that detail different pieces of vital information. Patent documents have a consistent structure that makes it easy to read with practice.

Images reviewing the various parts of a patent document.

Before You Search

Why conduct a patent search? People search patents for many reasons, most often because they have an invention they hope to patent. A search will determine whether an invention has patenting potential. Others search patents to find alternative approaches and suggestions to help resolve technological problems. Studies have shown that 80% of all patents hold information that is not published anywhere else in the world. By tapping into this tremendous resource, the searcher avoids "reinventing the wheel."

Patents can also provide information that will help someone fabricating a repair part, or may clarify the resources required to make an unfamiliar product work. Searchers also use patents for their historical usefulness and information, such as tracing the development of firearms, reviewing the inventive work of a particular inventor or company, or finding patents issued to an ancestor.

Although no one is required to conduct a patent search, many inventors prefer to do a preliminary search before they apply for a patent because a search may yield information that could affect the patenting potential of their invention. A search may not only help inventors decide whether to pursue a patent but also whether to modify their efforts to improve the probability of getting a patent.

Why Preliminary Searching?

Patent searching is a challenging task many searchers choose to do in order to decide on a course of action that will ultimately determine their legal rights. Conducting the searches is challenging precisely because the process involves multiple steps using resources with which many searchers are not familiar. By comparison, patent experts spend many hours in training and many hours searching inventions in their daily work.

For example, patent examiners at the United States Patent & Trademark Office (USPTO) spend about twelve hours investigating each patent application to determine whether the invention it describes is patentable. During that time, the examiner consults an average of thirty-eight databases containing patent and non-patent literature to determine whether the invention has ever before been described. Although a novice searcher may miss important patent information when searching, the best defense against these mistakes is practice, patience and the development of one's search skills.

Patents Search Plan

Making a Plan

You, the inventor or researcher, will be responsible for conducting your own search. The success of your search will depend heavily on your familiarity with the technological subject area of the invention. We recommend that you take the three preliminary steps below to insure the best and most complete search as possible.

Working Description

Prepare a working description of your invention for your own reference. This is for you to use while conducting your search. Librarians and staff will not need to see this information. You may wish to include your drawings to illustrate the invention and any data you may have gathered testing your invention.

As you write your description, include the following information:

  • Purpose: What does the invention do?
  • Application: What is it used for?
  • Structure: What is the invention made of and what are its parts?
  • Function: How does it work?
  • Consumers: Who might benefit from using it?

Non-Patent Information Sources

Investigate non-patent information sources relating to your invention to (1) develop a familiarity with other existing things that may have an impact on your ability to get a patent, and (2) become aware of the variety of words and phrases used to describe similar items and technology. Searching general sources may yield information useful in a number of ways to your specific patent search. Check with your local library about the availability of sources such as these:

  • General encyclopedias.
  • Technical or scientific encyclopedias.
  • Magazine and journal articles (often available on-line from the Penn State University Libraries).
  • Technical reports and working papers.
  • Trade catalogs where you might find similar items for sale.
  • Thomas Register.
  • Internet (try several search engines, none cover the entire Internet by themselves).

Checking on other products' patent numbers can also provide valuable information when doing your own search. Patent numbers can be found:

  • On manufactured items and their packaging.
  • In scientific and technical literature (scientific journals, working papers, trade journals).
  • Scifinder Scholar and other chemistry and pharmaceutical databases.

Research the Marketplace

The more you know about existing devices and technology that relate to your invention, the more prepared you will be to conduct your preliminary search. Having this sort of information will assist you in deciding on a course of action for your potential patent. Keep these hints in mind as you begin your research:

  • Try to determine where your device or technology will be used.
  • What existing items will your invention replace?
  • What consumers would buy your invention? Name the consumer groups, professions, industries, etc. that might want or need your invention.
  • Where do consumers generally purchase equipment or supplies like what you have invented? Would this be a potential marketing outlet for your invention?

Patent Search Resources

A preliminary patent search using Web resources can be done to a degree. The basic complement of tools is available at the USPTO Web site. This tutorial is designed to give searchers a solid process for accomplishing such a task.

Additional resources are available in Patent & Trademark Resource Centers (PTRCs), such as the Physical and Mathematical Sciences Library at Penn State. These resources include:

  • Staff trained to help you understand how to use patent search tools
  • Patents Research Guide which lists other internet resources for patent research
  • A complete collection of patents on DVD-ROM, for downloading large numbers of patents at once
  • Related patent, business, scientific, technical, and legal information, including books and other materials. Some for use in the library only and some available to be checked out.

Please note: Librarians and library staff are familiar with patent search resources and can demonstrate the use of computerized databases and other resources for searching. We are not trained or licensed legal professionals. This means that we are not able to advise you regarding any legal matters, including whether or not your invention is patentable, nor can we provide legal assistance for you. A database of registered patent attorneys is available on the USPTO Web site.

Choose Your Search

The search methods detailed in this tutorial are based on the U.S. Patent Classification system developed and maintained by the USPTO. If you are searching for patents based on subject matter, the U.S. Classification search is most useful because every patent is assigned to a specific set of classifications. While Keyword searching is useful, complete search results are less likely due to the inconsistency of terminology used in the full text of patents.

Doing a search on patents can be complex and lengthy but there are resources available to you free of charge that can help you refine your search for the most efficient results, get exactly the information you need, and pursue your own patent. We have selected the best of these for the Trademarks Research Guide from Penn State University Libraries.

The United States Patent & Trademark Office from the United States Department of Commerce offers an overview of this agency as well as information about nearly anything the inventor would like to know about patent and trademark policies and procedures.

Patent Number Searching

Although patent numbers are often displayed in products or packaging, patent searchers will also encounter patent numbers regularly as they investigate "non-patent" literature, such as scientific and technical reports. Patent numbers are also commonly available and accessible when gathering information about products available for sale or use in industry.

A good strategy for an inventor trying to determine likely markets for his or her invention includes carefully investigating products similar to one's own invention that already exist. Determine differences and similarities between these and your own product. Be sure to note any and all patent numbers shown on the product, its packaging, a manufacturer's website, or on any literature describing these items.

Below is a short video demonstration of a patent number search in the USPTO PatFT database.

When accessing a patent using the patent number, the final result of this search will be a display of patent information. Part of the patent document is the "Current CPC Class," which lists the classifications of the patent. These will help to identify additional patents that are closely related through classification searching.

Classification Search

The USPTO organizes all patents into the Cooperative Patent Classification (CPC) system. This system is an important tool for searching patents that relate to specific subject matter or share certain features in common. For example, all patents for pickup truck bed liners will be found in the same classification regardless of the actual words used to describe them. Each classification represents a group of 50 to 300 patents that share certain features, as set forth by the classification system. The CPC classification code is a sequence of letters and numbers.

For example, the sequence "G06Q 10/087" means:

  • section G
  • class G06
  • subclass G06Q
  • group 10
  • subgroup 087

Classification searches cover all utility, design and plant patents issues by the U.S. Federal government (1790 to present) and patent applications published by the USPTO (April 2001 to present). This search method does not include foreign patents or non-patent literature (NPL), such as technical publications, scientific journals, trade catalogs, and books.

Advantages: Since classification searching relies on the features of a patent, rather than the words used to describe the patent, all patents that utilize specific features will be returned as a search result. Additionally, classification searches will retrieve all patents from 1790 to present; there is no date restriction.

Disadvantages: Searchers new to the concept of classification searching will ideally spend time learning how to find and use classifications to retrieve patents. Also, the development of new classifications is a reactive process which means that the USPTO develops new classifications as a result of new patent trends. Consequently, new searchers may have difficulty finding patents in very new technological areas.

Below is a short video on finding classifications on the USPTO Classification Web Site.

Keyword Search

Keyword searching can find patents where specific words are used in the patent document. You can search in the "full text," the entire patent, or in specific "fields," or parts of the patents.

Advantages: Keyword searches are quick and don't require highly specialized search skills. Keyword searches are also most appropriate for technology that does not easily fit into one classification.

Disadvantages: Keyword searches depend solely upon the searcher's ability to anticipate and guess at how an attorney or inventor may have described an invention. Additionally, the USPTO website only allows keyword searching starting in 1976. Older patents can be searched in full text only on Google Patents.

Below is a short video on finding patents from company or inventor names.

Books on Patents and Trademarks

Available at the Physical and Mathematical Sciences Library, 201 Davey Lab. Located next to the PTDLP computer.

About the Patent Search Tutorial

  • Produced by: Penn State University Libraries.
  • 2013 Version by John Meier with special thanks to Amanda Clossen and Vicki Brightbill.
  • 2010 Version by John Meier and Michael Petner.
  • Original version by Sylvia DeSantis, Kevin Harwell, and Jason Russler Selected for the PRIMO in Summer of 2003.

Visit the Patent & Trademarks Research Guide.



John Meier
Science Librarian
Physical and Mathematical Sciences Library
201 Davey Laboratory
University Park, PA 16802

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