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The patent attorney's office which acts as the contact point for patent application and trademark application to China.

BY International Patent & Trademark Firm

BY International Patent & Trademark Firm paves the road of the intellectual property leading to all over Japan and all over the world from Nihonbashi in Japan.

Patent Attorneys

About Us

BY International Patent & Trademark Firm

Suite 804, LXS Muromachi,
1-10-10 Nihonbashi Muromachi, Chuo-ku, Tokyo
103-0022 Japan
E-mail. info@by-patent.com

Patent Attorneys in Japan


Fumihiko Yagisawa

Patent Attorney

Career ・Worked in TORAY Industries, Inc.
・Patent Firm in Japan
・BY International Patent & Trademark Firm, CEO
Specialized field Dispute of a patent, design patent and trademark in Japan, Research of infringement and invalidation, Application in Japan and to the foreign countries, Technology consulting, Foreign intellectual property businesses


Takeshi Sato

Patent Attorney
First class authorized architect

Career ・Worked in construction company
 A spot management, construction plan, multiplication
・Worked in a Patent Firm
 Patent application, Reason for Refusal, Invalidation judgment, Lawsuit
Specialized field Building, Amusement machine, Machine, Daily necessities, Plant, Production system, Software, Business patent


Tomohiko Kogi

Patent Attorney

Career ・Worked in a foreign-affiliated vendor (System engineer of communication)
・Worked in a Patent Firm
 In charge of patents of the foreign-affiliated major IT company
 Manager in charge of patents of the domestic major amusement machine manufacturer
 Contracting intellectual property business of Major Internet company
Specialized field Systems, Software, Structure, Technology development Consulting

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