Prolific inventor

Thomas Alva Edison was widely known as the America's most prolific inventor, even after his death in 1931. He held a total of 1,093 U.S. patents (1,084 utility patents and 9 design patents). In 2003, he was passed by Japanese inventor Shunpei Yamazaki. On February 26, 2008, Yamazaki was passed by Australian inventor Kia Silverbrook. Yamazaki passed Silverbrook in 2017.

Prolific inventors with 200 or more worldwide utility patent families are shown in the following table. In many cases, this number is also the number of U.S. utility patents granted. A patent family is a set of patents filed in various countries to protect a single invention.

This table was current as of August 7, 2017^[update]. The columns are defined as follows:

As the average number of patents per inventor is around 3, some sources define prolific inventors as five times above the average (in terms of patents), leading to a threshold of 15 patents. However, this table currently has an arbitrary cut-off limit for inclusion of 200 patent families. This is purely for practical reasons – there are 139 inventors throughout history with more than 200 utility patent families, but tens of thousands of inventors with more than 15 patents. The threshold of 200 patents means that some famous prolific inventors such as Nikola Tesla are not included in this list, as Tesla had 111 patents.

This table is a ranking of the most prolific inventors, not necessarily the most significant inventors. The significance of inventions is often not apparent until many decades after the invention has been made. For recent inventors, it is not yet possible to determine their place in history.

The common symbol for inventiveness, the light bulb, is a perfect example. The first incandescent light bulb was invented by British chemist Sir Humphry Davy in 1802. Many subsequent inventors improved Davy's invention prior to the successful commercialization of electric lighting by Thomas Edison in 1880, 78 years later. Electric lighting continued to be developed. Edison's carbon filament light bulb was made obsolete by the tungsten filament light bulb, invented in 1904 by Sándor Just and Franjo Hanaman. It is this that forms the popular conception of a light bulb, though there are other major forms of lighting. The principle of fluorescent lights was known since 1845, and various inventors, including Edison and Nikola Tesla worked on them without commercial success. Various improvements were made by many other inventors, until General Electric introduced "fluorescent lumiline lamps" commercially in 1938, first available to the public at the 1939 World's Fair. LED lamps also have a long history, with the first light-emitting diode (LED) invented in 1927 by Oleg Losev. LEDs were initially of low brightness, and have been used as indicator lamps and seven-segment displays since 1968. It wasn't until the development of high efficiency blue LEDs by Shuji Nakamura in the 1980s that white LEDs for lighting applications became practical. Although higher cost than incandescent light bulbs, LEDs have higher efficiency and longer life and may finally displace light bulbs in general lighting applications. In each case, more than 50 years passed between the initial invention and commercial success in general lighting applications.

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