Types of Patents

There are three types of patents, namely a design patent, a utility patent and a plant patent.  A reissue patent is issued to correct an error in an already issued design, utility or plant patent.  It does not affect the period of protection offered by the original patent.

A design patent protects the ornamental appearance of an invention.  It offers a relatively narrow scope of protection because the scope of protection is essentially dictated by what is shown in the drawings of the patent.  Generally speaking, “what you see is what you get.” See US D625,246 to view a sample design patent.

A utility patent protects a new and useful process, machine, article of manufacture or composition of matter, or any new and useful improvement thereof.  It offers a relatively broad scope of protection because the scope of protection is dictated by words (i.e., a narrative portion of the application, referred to as the claims).  Generally speaking, the scope of protection is not limited to what is shown in the drawings, as is the case of a design patent.  A utility patent includes among other parts, a written description and claims.  As a rule, the written description should be as detailed as possible, using non-definitive terms.  It should describe the invention in its preferred embodiment (i.e., the preferred design) and alternative embodiments (i.e., alternative designs).  The claims, on the other hand, should include as few words as possible.  Fewer words offer a broader scope of protection.  See US 7,974,720 to view a sample utility patent. 

Upon comparing a design patent and a utility patent, it should be readily noted that the design patent has a brief written description, setting forth the name of the article followed by a description of the drawing figures and often a disclaimer.  A single claim is drawn towards the article that is shown and described.  It should be noted that a design patent may have only one claim

The utility patent includes a comprehensive written description.  It includes a background of the invention, which includes a description of the field of the invention and a brief description of the prior art, often referring to a problem being solved by the invention.  The utility patent, like the design patent, has a description of the drawing figures.  This is followed by a detailed description of the invention.  The detailed description is followed by at least one claim, but typically includes numerous claims, including one or more independent claims and dependent claims, the latter depending from independent claims.  The claims are followed by an abstract that provides a summary of the written description. 

A plant patent protects distinct and new varieties of asexually reproduced plants.  See US PP22,611 to view a sample plant patent. 

The term of a design patent is 14 years from the date that it grants.  No maintenance fees are required for design patents.

The term of utility and plant patents is 20 years from the effective filing date (i.e., the actual filing date or priority date) of the patent application.  Utility patents are subject to maintenance fee payments (to enjoy the full term of the patent) and terminal disclaimers, barring any patent term adjustment (PTA).  Unlike utility patents, plant patents are not subject to the payment of maintenance fees.

To check on the status of a US patent or pay a maintenance fee, see Patent Maintenance Fees.  The patent term adjustment (PTA) is printed on the cover sheet of the patent.  To find out more about patent term adjustment, see Patent Term Adjustment (PTA) Questions and Answers.

If you have a question about types of patents, askme at thedford@askmeip.com.