Updated October 29, 2020:

The field of invention in patent applications refers to the broad area of technology under which the patent falls. Typically, patent applicants describe their field of invention in two sentences. The first sentence paraphrases the class definition, and the next works as a subclass definition.

For instance, a field of invention may read like this: “This invention relates to hand tools. To be more specific, this invention pertains to groove joint pliers.”

Describing Your Invention in a Patent Application

Whether you're preparing a provisional or non-provisional patent application, you'll use certain terminology relevant to your field. You may prepare your application on your own or with help from a patent agent or patent attorney. Before proceeding, look over what you've written to see if you're using any terms that have a particular meaning.

With each of these terms, ask yourself if it's a commonly understood term by skilled people in the field. If it's a commonly understood term in the industry, you should use it the same way that others in the industry use it. This isn't the time to be creative.

How to Write Your Description

Following some tips on how to write your invention's description can help you draft one properly. You should use the following order unless there's a better, more economical way to write the description.

The order is as follows:

  • Title
  • Technical field
  • Prior art and background information
  • Description of the way your creation addresses a technical problem
  • Figures list
  • A detailed description of the invention
  • An example of intended use
  • A sequence listing

To start, you may find it helpful to jot down notes and brief points to cover from each of these headings. When you polish your description, you can follow the below outline.

  1. Start on a new page with your invention's title. The title should be precise, short, and specific. For instance, if your creation is a compound, title it "Carbon tetrachloride," not simply "Compound." Don't name the invention after yourself or use new words. Give it a title that people can easily find through a keyword search if they're looking for your patent.
  2. Write a statement that gives a broad definition of the technical field that relates to your invention.
  3. Offer background information that others will need in order to search for, examine, or understand your invention.
  4. Talk about problems that inventors in this field have come across, as well as how they tried to solve them. This is usually referred to as giving prior art, and it's previously published information relating to your invention. This is usually where applicants quote previous, similar patents. State how your invention can solve one or more of these problems, in general terms. What you want to do here is show how your invention presents a new, different angle.
  5. List your drawings by figure number and provide brief descriptions of what they illustrate. Refer to the drawings in your detailed description. Use the same figure numbers as reference for each element.
  6. Provide a detailed description of your intellectual property so that another person could reproduce at least one version of your creation based on your description. Your description needs to fit all possible alternatives. Product descriptions should describe all parts, how they connect, and how they work together. Process descriptions should describe every step, what makes changes, and the end result.
  7. Provide at least one example of how your invention is to be used. Don't forget to include warnings that would be common in your field so that other people can avoid failure.
  8. Provide the sequence list of your compound if this is relevant to your invention. A sequence isn't included with any drawings; it's considered to be part of your description.

Each industry has its own terminology that people within are familiar with. When you apply for a patent, you're providing descriptions and instructions that anyone in that particular field should easily understand. They should know the terms you use.

This isn't the place to create new terms, which can be confusing to patent examiners. Following all of the specifications in a patent application increases your chances of being successful.

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