How long does a patent last?
How long a patent lasts depends on the type of patent being issued and the country issuing the patent. For example, under recent changes in the laws, in the United States, patents are now granted for a term of 20 years from the date of application (14 years for design patents). Different rules apply for patents from applications filed before June 8, 1995. Patents may be extended only by a special act of Congress, except for certain pharmaceutical patents.
After the term of the patent has expired, the person holding the patent loses the right to stop others from utilizing the invention. At that time, anyone can make use of the invention without permission of the patent holder.
Design patents last for 14 years. A design patent is issued for designs placed on manufactured items. Examples would include various skins for iPods or fabrics used in the fashion industry. To learn more about design patents visit the United States Patent and Trademark Office (USPTO) website's section on design patents.
Plant patents last for 20 years. A plant patent according to the U.S. patent office, “is granted by the government to an inventor (or the inventor's heirs or assigns) who has invented or discovered and asexually reproduced a distinct and new variety of plant, other than a tuber propagated plant or a plant found in an uncultivated state.” An example would be the annual rose created for the Rose Bowl Parade. To learn more, visit the USPTO's plant patents section.
A utility patent is the most common patent issued, and it lasts for 20 years. Utility patents are granted for inventions such as machines, machine parts, or even a new child’s toy. You can learn more about utility patents and the patenting process on the USPTO's website.
International patents can last anywhere from 6 to 20 years, depending on the type of patent and the country where you are seeking patenting. On average, countries that are part of the World Trade Organization will grant 20-year patents.