小山 立家

Intellectual Property


Clients turn to Tatsuya Koyama for his extensive experience in intellectual property (IP) matters, particularly in offensive patent litigation. Tatsuya helps clients protect and maximize the value of their IP by turning clients’ patent assets into profit. Tatsuya has represented clients in matters before US federal district courts and the International Trade Commission (ITC). He has been involved in all stages of district court and ITC patent litigation from pre-suit diligence to trial.


  • Certain Smart Televisions, 337-TA-1338 (ITC) (2022-2023). – Representing Maxell in a complex litigation against Vizio, Inc. Managed the day-to-day technical aspects of two of the four asserted patents related to smart televisions, including drafting claim construction briefing and leading the oral argument at the Markman hearing, securing favorable claim constructions on all terms; oversaw and managed technical experts on both infringement and validity cases to prepare for trial.
  • Maxell, Ltd. v. TCL Electronics Holdings Ltd. et al. (E.D. Tex. 2023) – Representing Maxell in a complex litigation involving six patents related to smart televisions.
  • Maxell, Ltd. v. Samsung Electronics Co., Ltd. et al. (E.D. Tex. 2023) – Representing Maxell in seven-patent case related to smartphones, smart appliances, and the like.
  • Maxell, Ltd. v. Vizio, Inc. (C.D. Cal. 2021-2023) – Representing Maxell in a complex litigation involving seven patents related to smart televisions such as casting, slide show, frame rate control, and display control.


  • シカゴ大学, LLM
  • 慶応義塾大学 , LLB
  • 慶応義塾大学 , MSc, Engineering
  • 慶応義塾大学 , BSc, Engineering


  • 日本弁理士会
  • ニューヨーク州弁護士
  • ワシントンDC弁護士
  • ※但し、外国法事務弁護士の登録はない。


  • 英語
  • 日本語