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Home >> Research & Instruction >> Research Services Blog >> Searching for Patents
Partial Patent Definition

What is a Patent?

A patent grants an inventor or inventors the exclusive right to their intellectual property (IP) for a set period of time. Patents are issued by governments or regional organizations, but there is no such thing as a true universal patent. Instead, inventors may file individual applications in multiple countries or file an international application under the Patent Cooperation Treaty (PCT) system. Over 140 countries participate in PCT and these applications are administered by the World Intellectual Property Organization (WIPO). The applications are then investigated by the patent offices in the individual membership countries. Once a patent has been granted, the owner retains exclusive rights to prevent others from making, using, selling, or otherwise benefitting from the invention without the owner’s permission.

Why is Patent Literature Important?

Most patents are granted for 20 years giving the inventor market leverage and time to recoup the costs of researching, designing, and manufacturing. In return for a 20 year monopoly on their technology, the inventor must fully disclose detailed information about their invention in the patent. Inventors must also include evidence of known prior art (proof of existence of similar IP In the public domain) to prove that their invention is novel (unique and new), useful, and non-obvious. It is estimated that 10-90% of technical information in patents is found nowhere else. In academic settings researchers are encouraged to publish their findings in scholarly journals or to present at conferences, but private companies do not openly share their IP for proprietary reasons. This makes patents a valuable source of scientific and technical literature, a window into the private sector if you will. Patent literature can help you avoid researching what is already known, keep you up to date with cutting edge technology, locate experts in the field, business partners, or new licensing opportunities, or to investigate companies where you may like to apply or to gain competitive information on a rival business.

Types of Patents & Examples

Anybody can be an inventor and most patents fall under three categories, utility, design, and plants. The most common type being the utility patent which protects inventions such as devices, compounds, and processes. Design patents protect ornamental design applied to a manufactured product, and plant patents protect new varieties of asexually reproducing plants. 

Patent Type





Where Can I Find Patent Literature?

Patents are public documents and are accessible via a wide range of online databases. There are a few things to know about patents before you search. Patents aren’t listed by product name and don’t describe inventions as they appear in the market place. Oh, and patents are not easy to read because they are written in technical and legal language. Here is a list of online patent databases to search. ‚Äč

  • USPTO United States Patent and Trademark Office: Full-text and images of U.S. patents from 1790 to current

  • Espacenet European Patent Office: Nearly 80 million patent documents from 50+ countries

  • Google Patents Full-text and images from 17 patent offices

  • PatentScope WIPO International and National Patent Collections

  • SciFinder Science patents from major patent offices world wide (requires registration for SDSU users)

  • FreePatentsOnline Full-text and images of U.S. patents from 1974+ and European patents 2000+


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