Patent and Prior Art Basics

Video: Introduction to Patents and Prior Art


We put together this 20 minute webinar to provide an introduction to patents and prior art. It's designed to be an introduction to the basics of these topics. You can also read below.



What is a patent?


Patents protect and encourage innovation. In exchange for public disclosure of an invention, governments grant exclusive, but temporary, rights to practice that invention to the inventor or his/her designated assignee. In doing so, the patent holder is guaranteed acknowledgement of her new idea and several years of exclusivity, but the information is also made public, allowing others to build on the idea.

Rules governing patents vary by nation. In the US, patent law is determined by the US Congress and administrated by the US Patent and Trademark Office. The World Intellectual Property Organization (WIPO), a special agency of the United Nations, coordinates international patent issues. 

In order to receive a patent in the US, an invention must meet three general criteria. The invention must be:

1. Novel - At least some aspects of the invention must be new (Optimizations are not generally considered new inventions.)

2. Useful - The invention should have a credible utility

3. Non-obvious - The invention should not be obvious to a person skilled person in the respective area

For detailed information about patent rules in the US, see the US Patent and Trademark Office’s website


What is the process to get a patent?


The patent process varies by nation, but generally consists of a patent application, a review of the application by the nation’s patent office and then granting or denial of the patent. While this basic process sounds simple, in reality it is often complex and very expensive. For example, it could take up to several months to prepare a complex patent application and, in the US, it can take 2-5 years for the patent office to grant or deny a patent.


What is Prior Art?


Prior art is one of the key concepts in patent applications and litigation. Prior art encompasses all information that has been disclosed to the public, in any form, anywhere in the world, about an invention before a given date, usually the filing date of a given patent. Prior art includes not only previous patents, but also any other published materials, including scientific papers, advertisements, etc. (in patent lingo, any publications unearthed in a prior art search that aren’t patents are called non-patent literature or NPL).

If an invention was described in prior art, a patent on that invention is not valid. Therefore, patent applications must include relevant prior art and prove that art does not apply directly to the pending invention. Likewise, someone trying to prove that a specific patent is invalid can do so by finding prior art -- a mention of the invention in any publication -- from before the patent was filed.


Types of Prior Art Searches


Prior art searches are undertaken for a variety of reasons. Here are the main types:

Patentability/Novelty: A search conducted to determine if an invention is novel and, therefore, patentable. These searches aim to determine if key elements of an invention have previously been disclosed in any publication. They are generally performed when an inventor or company is deciding to apply for a patent and by patent office employees reviewing patent applications.

Validity: A search conducted after a patent has been issued to determine whether or not the patent office overlooked existing prior art, which could invalidate the patent. These searches are conducted by entities accused of infringing on a patent (if they prove the patent invalid, there is nothing to infringe upon) or by entities with a financial stake in a patent (considering buying or licensing it).

Clearance/Freedom to Operate: A search of issued patents to determine if an idea infringes on any existing patents. If it does, the inventor may attempt to invalidate those patents, design a work-around or even abandon the idea. Also, a clearance/freedom to operate search may reveal that an idea is covered by patents in certain countries, but not others, and allow an inventor to act accordingly.

State of the Art: A search that aims to establish the overall “state of the art” for a particular invention or field, including patents and non-patent literature. Generally, companies perform these searches to understand the current situation in a given field and their place within it. They can identify the latest technology, see what competitors are doing and create their plan for moving forward.

Patent Landscape: These searches are detailed analyses of all the patents related to a certain technology. They generally start with a state of the art search to find the relevant patents and then include further analysis of the patents involved. Patent landscape searches generally include graphical representation of information about the patents.


Parts of a Patent


All US patents are structured the same way. Here are the parts of a patent, organized by how they appear in Patexia’s patent database.


  • Title
  • Publication Number – Assigned when patent is published
  • Application Number – Assigned when application is submitted
  • Date patent was issued
  • Date patent application was filed
  • Inventor names – Inventors are always people, never companies or organizations.
  • Assignee names (if applicable) – The entity with the legal right to the patent. This can be a person or organization. For example, if an inventor is working for a company, the company generally owns the patents that result from his work.
  • US Classification number – Roughly 450 classes and 150,000 subclasses correspond to various subject matters. 


  • References – Older patents, articles or books that relate to the patent and are included in the patent application 
  • Forward Citations – Subsequent patents that list this patent as a reference.


  • Background information and explanation of the patent. The description should be detailed enough for someone skilled in the field to reproduce the invention.


  • This section outlines the scope of legal protection granted by the patent, making it the most important section of any patent.
  • There are two types of claims: independent claims, which stand alone, and dependent claims, which depend on one or more other claims and only have meaning when read in conjunction with those claims. Patexia’s unique claim tree structure graphically displays the relationships between independent and dependent claims in every patent, allowing viewers to immediately understand the claim hierarchy.

Drawings and Figures

  • Can be viewed in the pdf of the patent


Patexia is not a law firm and cannot provide legal advice. Although we take every reasonable effort to ensure that the information on our website and documents are up-to-date and legally sufficient, the legal information on this site is not legal advice and is not guaranteed to be correct, complete or up-to-date. Therefore, if you need legal advice for your specific problem, you should consult a licensed attorney. This site contains links to other resources and businesses on the Internet. Those links are provided as citations and aids to help you identify and locate other Internet resources that may be of interest, and are not intended to state or imply that Patexia sponsors, is affiliated or associated with, guarantees, or is legally authorized to use any trade name, registered trademark, logo, legal or official seal, or copyrighted symbol that may be reflected in the links.