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Sigma Corporation

USPTO Granted Patents = 31

Trademarks = 7

Forward Citations = 1,483

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32 inventors (with patents filed for the assignee):

Stuart J Box (3 out of 3 patents)

Yuji Nagao (3 out of 9 patents)

Takashi Hagiwara (3 out of 29 patents)

4. Charles J Longacre (2 out of 2 patents)

5. David F Toler (2 out of 2 patents)

6. Kaoru Kanda (2 out of 5 patents)

7. Kikuo Nakamura (2 out of 3 patents)

8. Antonio Capuano (2 out of 2 patents)

9. Kunihiko Kanda (2 out of 2 patents)

10. Eric Ireland (2 out of 2 patents)

11. Satheesh Manicka Seshaiyer Chandrasekaran (1 out of 1 patent)

12. Hirokazu Suzuki (1 out of 40 patents)

13. Tatsuhiko Fujioka (1 out of 1 patent)

14. Kuniyoshi Sato (1 out of 2 patents)

15. Takashi Komori (1 out of 15 patents)

Core Competencies:

Modular Adjustable Weight Container

Imaging Optical System

Telephoto Zoom Lens

Joint Restraint Assembly

Game Machine

Slot Machine

Keno Game

Component Measuring Apparatus

Diaphragm Control Lens

Pusher Game Apparatus

Horse Racing Game

Amusement Device

31 patents: Sort by Forward Citations

1. 12747062 - Modular adjustable weight container (2026-09-29),

2. 12742949 - Imaging optical system (2026-09-22),

3. 12724248 - Large aperture ratio telephoto zoom lens (2026-09-01),

4. 12448185 - Plastic meter lid and frame assembly for an in-ground meter box (2025-10-21),

5. 12196935 - Imaging optical system (2025-01-14),

6. 11318515 - Large diameter pipe rounding tool and method of use (2022-05-03),

7. 10036497 - Joint restraint devices and methods of using same (2018-07-31),

8. 7266875 - Joint restraint assembly (2007-09-11),

9. 7185924 - Joint restraint assembly (2007-03-06),

10. 6012981 - Game machine for single player (2000-01-11),

11. 5713572 - Pusher game apparatus (1998-02-03),

12. 5618233 - Running body and racing game apparatus using the same (1997-04-08),

13. 5591081 - Card game amusement device (1997-01-07),

14. 5580055 - Amusement device and selectively enhanced display for the same (1996-12-03),

15. 5507490 - Game apparatus (1996-04-16),

Sigma Corporation, headquartered in Tokyo, Japan, is a prominent player in the imaging and optical equipment sector. The company specializes in the development and manufacturing of high-quality lenses, cameras, and photographic accessories, catering to both professional and amateur photographers. Sigma is recognized for its innovative approach to optical technology, focusing on enhancing image quality and performance across various applications. With a commitment to precision engineering, Sigma continues to advance its research in imaging technologies, contributing significantly to the photography and videography industries.

Profile summary based on public USPTO records.

Company Badge

USPTO Data Jan 1 1976 - Sep 29 2026

31 Patents

#1,041 in Tokyo

#2,269 in Japan

#21,217 in the World

Sigma Corporation

Forward Citations = 1,483

32 inventors:

Stuart J Box (3 out of 3 patents)

Yuji Nagao (3 out of 9 patents)

Takashi Hagiwara (3 out of 29 patents)

4. Charles J Longacre (2 out of 2 patents)

5. David F Toler (2 out of 2 patents)

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