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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.

Inventors with 200 or more worldwide utility patents are shown in the following table. While in many cases this is the number of utility patents granted by the United States Patent and Trademark Office, it may include utility patents granted by other countries, as noted by the source references for an inventor.

This table was current. The columns are defined as follows:
 * Inventor: The name of the inventor.
 * # of patents: This is the number of utility patents that have been issued. Only utility patents (or the international equivalent) are listed, as a utility patent is a patent for an invention. Not all patents are for inventions. Other patent types include: design patents for the ornamental design of an object; plant patents for plant varieties; and reissue patents, where a correction is made to an already granted patent. This list does not include patent applications (patents pending) as there is no guarantee that a patent application actually describes a novel invention until the patent is granted.
 * Country: This is the country of birth or upbringing of the inventor, where known. If unknown, this is the country of residence identified in the inventor's patent filings.
 * Active: The first and last year in which an inventor received a patent issuance, except when activity was prior to digital records, in which case year of birth (b) and death (d) may be substituted. If an inventor's first year is 1976 or a few years after, there may be activity prior to this; earlier dates are not present in the primary source, and would require a secondary source.
 * Main fields of invention: These are the main areas that the inventor is or was active in.

Threshold for inclusion
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 patents. This is purely for practical reasons – there are 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.

Significance of inventions
This table is a sortable list of the most prolific inventors as measured by utility patents granted. It does not include other types of invention, such as inventions that were never applied for nor granted, for which there is no known source. Nor does the table attempt to measure the significance of an inventor and their inventions. 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 an 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.

Various published lists
Rankings of prolific inventors have been published at various times. However, until the patent records were digitized, these lists were very tedious to prepare, as many thousands of patent records had to be checked manually. Even after digitization, it is still not a simple process. While the USPTO keeps statistics for annual rankings of inventions assigned to companies, it no longer publishes rankings of individual inventors. The last such list was published by the USPTO in 1998. Also, patents predating 1976 have not yet been digitized in the USPTO records. This means that patents before 1976 will not be included in a USPTO search by inventor name, and the number of patents granted before 1976 must be added to current searches.

Popular Science (1936)
In January 1936, Popular Science published a list of the "most prolific living inventors to be found in America today".

Thomas Edison was not included in the list, as he died in 1931, five years earlier.

Time Magazine (2000)
On December 4, 2000, Time Magazine published a list of the "top five inventors".

This list only included U.S. inventors, so omitted Canadian inventor George Albert Lyon, with 993 U.S. patents at the time of publication, Japanese inventor Shunpei Yamazaki, with 745 U.S. patents, and Béla Barényi, with 595 German patents. Also omitted were John F. O'Connor with 949 U.S. patents, and Carleton Ellis, with 753 U.S. patents at the time of publication.

USA Today (2005)
On December 13, 2005 USA Today published a list of "the top 10 living U.S. patent holders":

This research was performed by ipIQ of Chicago (now "The Patent Board" ) and 1790 Analytics of New Jersey. This list only considered living inventors, and thus did not include such prolific inventors as Thomas Edison, Melvin De Groote, and Elihu Thomson. This list included design patents, which are not patents for inventions.

Condé Nast Portfolio (2007)
On October 15, 2007 Condé Nast Portfolio Magazine published a list of "the world's most prolific inventors alive":

This research was performed by The Patent Board, a Chicago patent research and advisory firm. As with the USA Today list, the Portfolio list only considered living inventors, and thus did not include such prolific inventors as Thomas Edison. This list also included design patents, which are not patents for inventions.

Business Insider (2011)
On 6 May 2011 Business Insider published an article titled: "The Ten Greatest Inventors In The Modern Era" containing the following list:

This list included living and dead inventors, and only included granted utility patents (patents for inventions).

Strutpatent.com (2012)
Strutpatent.com publishes a list of the "Top 10 Inventors" listing inventors ranked by US patents (of all types) issued since 1990:

This list included only patents granted since 1990, and includes design patents as well as utility patents.

Annual lists (2007–2012)
Strutpatent.com publishes weekly, monthly, and annual lists of the top ten categories, inventors and assignees of US patents since 2007. These lists include all patent types, not just patents for inventions (utility patents).

The top ten inventors of US patents for 2007: The top ten inventors of US patents for 2008: The top ten inventors of US patents for 2009: The top ten inventors of US patents for 2010: The top ten inventors of US patents for 2011: The top ten inventors of US patents for 2012: This table omitted Rick Allen Hamilton II. The USPTO database shows Hamilton was an inventor or co-inventor of 128 US patents granted in 2012, which would place Hamilton at 6th rank for 2012.

Differences between lists
Differences in patent numbers between the various lists are due to several reasons:
 * The lists were created on different dates. As many of the inventors in the lists are still active, the number of patents they hold are increasing.
 * While the U.S. Patent and Trademark Office (USPTO) is the primary source for U.S. patent information, only patents issued since 1976 can be electronically searched by the inventor's name at the USPTO website. For some of the listed inventors, such as Thomas Edison, all of their patents predate 1976, so other sources must be used.
 * Often entities list the worldwide total number of patents that they hold. This is not the same as the number of inventions, as a patent in one country may be for the same invention as a patent in another country. The set of patents covering a single invention in different countries is a Patent family.
 * The Time, USA Today and Portfolio lists show the total number of U.S. patents, including patents for designs (Design patents) as well as patents for inventions (Utility patents).
 * The annual lists from strutpatent.com list only those patents issued in the particular year to the inventor, not all of the inventor's patents.