List of prolific inventors

Thomas Edison was widely known as the world's most prolific inventor.^[1][2] He holds a total of 1,093 U.S. patents (1,084 utility patents and 9 design patents).^[3] By 2005, he was passed by Japanese inventor Shunpei Yamazaki.^[4] Yamazaki was subsequently passed by Australian inventor Kia Silverbrook on February 26, 2008.^[5] Silverbrook currently holds 4,337 U.S. utility patents as at January 5 2012.^[6]

The top 45 most prolific inventors by worldwide utility patent families are shown in the following table. In many cases, this number is also the number of granted U.S. utility patents. A patent family is a set of patents filed in various countries to protect a single invention.

Inventor	Patent Families	Country	Total, INPADOC	Years	Main fields of invention	Ref
Kia Silverbrook	4,337	Australia	9,282	1958 -	Printing, Digital paper, Internet, Electronics, CGI, Chemical, MEMS, Mechanical, VLSI	[6][7][8][5][4][9][10][11][12][13][14]
Shunpei Yamazaki	2,739	Japan	10,823	1942 -	Thin film transistors, Liquid crystal displays, Solar cells, Flash memory, OLED	[15][16][8][4][9][17][10][11][12][13][14]
Paul Lapstun	1,144	Australia	3,087	19?? -	Printing, Digital paper, Internet, Electronics, CGI, VLSI	[18][19][8][10][11][12][13][14]
Thomas Edison	1,084	United States	2,332	1847–1931	Electric power, Lighting, Batteries, Phonograph, Cement, Telegraphy, Mining	[3][20][21][1][5][8]
George Albert Lyon	993	Canada	NA	1882–1961	Automotive, Stainless steel products	[22][8]
Leonard Forbes	974	Canada	1,315	1940 -	Semiconductor Memories, CCDs, Thin film processes and materials, VLSI	[23][24][8][9][10][12]
Donald Weder	960	United States	1,910	1947 -	Florist supplies	[25][26][8][4][9][17]
John F. O'Connor	949	United States	NA	1864–19??	Railway draft gearing	[27][8]
Melvin De Groote	925	United States	NA	1896–1963	Chemical de-emulsifiers	[1][8]
Gurtej Sandhu	912	India	1,478	1960 -	Thin film processes and materials, VLSI, Semiconductor device fabrication	[28][29][4][9][17]
Francis H. Richards	894	United States	NA	1850–19??	Mechanical, automation	[1][8]
Carleton Ellis	753	United States	NA	1876-1941	Margarine, Polyester, Anti-knock gasoline, Paint stripper	[30][27]
Warren Farnworth	742	United States	928	1954 -	Semiconductor packaging	[31][32][4][9]
George Spector	722	United States	747	19?? -	Gadgets, Toys	[9][33][4][9]
Jun Koyama	719	Japan	2,571	19?? -	Thin film transistors, Liquid crystal displays, OLED	[34][35]
Elihu Thomson	696	UK	NA	1853–1937	Electric power, Arc lamp, Electric motors, Lightning arrester, Arc welder	[1][27]
Salman Akram	691	United States	831	1967 -	Semiconductor packaging	[36][37][4][9]
William I. Wood	645	United States	3,581	19?? -	Proteins, Antibodies	[38][39][10][11]
Josef Theurer	626	Austria	4,939	19?? -	Railroad maintenance machines	[40][41][17]
Simon Walmsley	621	Australia	1,251	19?? -	Printing, Electronics, VLSI, Cryptography	[42][43][13][14]
Audrey Goddard	614	United States	3,462	19?? -	Proteins, Antibodies	[44][45][10][11]
Jerome Lemelson	606	United States	NA	1923-1997	Toys, Industrial robots, Cordless telephones, Fax machines, Videocassette recorders	[46][1][17]
Austin L. Gurney	609	United States	3,400	19?? -	Proteins, Antibodies	[47][48][10][11]
Jay Walker	603	United States	1,913	1955 -	Gaming machines	[49][50][14]
Béla Barényi	595	Hungary	1,238	1907-1997	Passive safety in automobiles	[51][52]
Paul J. Godowski	577	United States	2,648	19?? -	Proteins, Antibodies	[53][54][10][11]
Hideo Ando	576	Japan	1,756	19?? -	Optical recording	[55][56][14]
Tetsujiro Kondo	572	Japan	4,071	19?? -	Signal processing, Image processing	[57][58]
Artur Fischer	570	Germany	3,090	1919 -	Fasteners, Construction toys	[59][60]
Edwin H. Land	535	United States	1,216	1909-1991	Instant photography, Polarizing film	[61][62]
Henry Dreyfus	524	United States	2,102	1882-1944	Polymers, Synthetic fibers, Dyes	[63][64]
Kie Y Ahn	520	United States	689	19?? -	Thin film processes and materials, VLSI, Semiconductor device fabrication	[65][66]
Clyde C. Farmer	513	United States	830	18??-19??	Railway air brakes	[67][68][27]
Mark I. Gardner	511	United States	583	1955 -	Consumer electronics, Energy, Computers, Semiconductors, Physics	[69][70][4][9]
Heinz Focke	510	Germany	2,888	19?? -	Cigarette packaging	[71][72][4]
Tadahiro Ohmi	506	Japan	2,411	19?? -	Thin film processes and materials, Semiconductor device fabrication	[73][74]
Louis H. Morin	503	United States	721	18??-19??	Fasteners, Locks, Bobbins	[67][75]
Michael J. Sullivan	502	United States	1,182	19?? -	Golf balls	[76][77]
William Eby	473	United States	555	19?? -	Transgenic soybeans	[78][79]
Tobin King	468	Australia	1,239	19?? -	Printing, Digital paper, Mechanical	[80][81]
Eberhard Ammermann	452	Germany	5,091	19?? -	Fungicides	[82][83][17]
Hongyong Zhang	425	Japan	763	19?? -	Thin film transistors, Liquid crystal displays	[84][85]
John Hays Hammond, Jr.	417	United States	458	1888-1965	Radio control, Radio communications, Torpedoes	[86][87]
Ravi Arimilli	415	India	751	1963 -	Computer architecture, Semiconductor memory, Cache coherence, Symmetric multiprocessing	[88][89]
Wilhelm Brandes	411	Germany	2,924	19?? -	Fungicides	[90][91][17]

†This table was last updated on December 20, 2011.

• Inventor: The name of the inventor.
• Patent Families: This is the number of families of utility patents that have been issued. In many cases above, it is also the number of issued U.S. utility patents. There is a direct correspondence between the number of patent families and the number of unique patented inventions. The total number of worldwide patents does not correspond closely to the number of inventions, as each separate invention must be filed as a separate patent in each country for which patent protection is sought. Only utility patents are listed, as a utility patent is a patent for an invention. Not all patents are for inventions. Other patent types are: 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.
• Total, INPADOC: Worldwide number of patents of all types (utility, design, plant, etc.) This includes patent applications, and duplication of the same patent in multiple countries, so is usually an overestimate of the total number of inventions. This data is primarily from INPADOC, an international patent collection produced and maintained by the European Patent Office (EPO). For some inventors active before computer records were available, the total number of patents is not available (NA).
• Country: This is the country of birth of the inventor, where known. If the country of birth is unknown, this is the country of patent filing.
• Years: These are the birth and death years of the inventor, where known.
• Main fields of invention: These are the main areas that the inventor is or was active in.

Contents 1 Significance of inventions 2 Various published lists 3 Popular Science (1936) 4 Time Magazine (2000) 5 USA Today (2005) 6 Condé Nast Portfolio (2007) 7 Business Insider (2011) 8 Annual lists (2007-2011) 9 Differences between lists 10 See also 11 References

Significance of inventions

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. 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.^[17] 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 Magazine published a list of the "most prolific living inventors to be found in America today":^[27]

Rank	Inventor	U.S. Patents
1	John F. O'Connor	949
2	Elihu Thomson	696
3	Carleton Ellis	648
4	Henry A. Wise Wood	434
5	John Hays Hammond Jr.	360
6	Clyde C. Farmer	344
7	Ethan I. Dodds	321
8	Edward Weston	309

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".^[1]

Rank	Inventor	U.S. Patents
1	Thomas Edison	1,093
2	Melvin De Groote	925
3	Francis H. Richards	894
4	Elihu Thomson	696
5	Jerome Lemelson	554

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":^[4]

Rank	Inventor	U.S. Patents
1	Shunpei Yamazaki	1,432
2	Donald Weder	1,322
3	Kia Silverbrook	810
4	George Spector	723
5	Gurtej Sandhu	576
6	Warren Farnworth	547
7	Salman Akram	527
8	Mark Gardner	512
9	Heinz Focke	508
10	Joseph Straeter	477

This research was performed by ipIQ of Chicago (now "The Patent Board"^[92]) and 1790 Analytics^[93] 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^[9] of "the world's most prolific inventors alive":

Rank	Inventor	U.S. Patents
1	Shunpei Yamazaki	1,811
2	Kia Silverbrook	1,646
3	Donald Weder	1,350
4	George Spector	722
5	Gurtej Sandhu	674
6	Leonard Forbes	671
7	Warren Farnworth	635
8	Salman Akram	612
9	Mark Gardner	515
10	Joseph Straeter	485

This research was performed by The Patent Board,^[92] 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"^[8] containing the following list:

Rank	Inventor	U.S. Patents
1	Kia Silverbrook	3,847
2	Shunpei Yamazaki	2,061
3	Thomas Edison	1,084
4	George Albert Lyon	993
5	Paul Lapstun	969
6	Donald Weder	951
7	John F. O'Connor	949
8	Leonard Forbes	948
9	Melvin De Groote	925
10	Francis H. Richards	894

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

Annual lists (2007-2011)

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:^[10]

Rank	Inventor	U.S. Patents
1	Kia Silverbrook	502
2	Audrey Goddard	232
3	William I. Wood	232
4	Austin L. Gurney	225
5	Chang-Hwan Hwang	203
6	Paul J. Godowski	193
7	Shunpei Yamazaki	139
8	Paul Lapstun	129
9	Leonard Forbes	120
10	Victoria Smith	112

The top ten inventors of US patents for 2008:^[11]

Rank	Inventor	U.S. Patents
1	Kia Silverbrook	576
2	Chang-Hwan Hwang	198
3	Audrey Goddard	168
4	Austin L. Gurney	167
5	William I. Wood	166
6	Paul J. Godowski	153
7	Shunpei Yamazaki	143
8	Paul Lapstun	137
9	Chang-Soo Lee	129
10	Victoria Smith	122

The top ten inventors of US patents for 2009:^[12]

Rank	Inventor	U.S. Patents
1	Kia Silverbrook	444
2	Shunpei Yamazaki	137
3	Paul Lapstun	113
4	Bartley K. Andre	92
5	Daniele De Iuliis	92
6	Jonathan Ive	92
7	Matthew Rohrbach	92
8	Richard P. Howarth	91
9	Duncan Robert Kerr	91
10	Leonard Forbes	91

The top ten inventors of US patents for 2010:^[13]

Rank	Inventor	U.S. Patents
1	Kia Silverbrook	709
2	Paul Lapstun	191
3	Shunpei Yamazaki	162
4	Simon Walmsley	115
5	Bartley K. Andre	114
6	Matthew Rohrbach	109
7	Richard P. Howarth	108
8	Jonathan Ive	108
9	Duncan Robert Kerr	108
10	Daniel J. Coster	106

The top ten inventors of US patents for 2011:^[14]

Rank	Inventor	U.S. Patents
1	Kia Silverbrook	754
2	Paul Lapstun	268
3	Shunpei Yamazaki	163
4	Hideo Ando	162
5	You Yoshioka	153
6	Scott H. Wittkopp	126
7	James M. Hart	125
8	Edward K. Y. Jung	112
9	Simon Walmsley	112
10	Jay S. Walker	99

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.^[94] 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).

See also

• Timeline of historic inventions
• List of inventors

References