Home Our Team Timothy A. Cassidy

Timothy A. Cassidy


What you should know about me:

Facing complex intellectual property issues, including patent matters, requires the right experience and a creative solution-oriented approach. My strategic approach to representing clients not only draws on my significant patent and trademark litigation experience, but also on experiences managing patent portfolios of Fortune 100 companies for over two decades. 

  • Known for his business acumen & great taste in music 
  • Voted “Most Talented” in high school, later a member of No. 7 nationally ranked college and debate team
  • Have had nine patents I prosecuted become the subject of 5 different patent enforcement litigations that led to significant monetary settlements and judgements for our firm’s clients, in addition to downstream royalties and the accomplishment of other business objectives

Timothy’s Experience

Timothy manages and helps monetize patent portfolios for various domestic and international clients. He counsels clients on avoiding the infringement of third-party patents, opines on infringement and/or validity of individual patents, and advises on strategies for avoiding third party patent portfolios, all while focusing on meeting the overall business goals of the client.  

Although his background is in chemical engineering, Timothy has knowledge and experience in many diverse fields of technology, including polymer chemistry, polymer catalyst technologies, mechanical and electromechanical technologies, textile technologies, medical devices and technologies, and pharmaceutical chemistry.

Timothy uses his 20-plus years of experience to quickly and efficiently solve clients’ problems as they arise. He regularly prepares and prosecutes patent applications before the U.S. Patent and Trademark Office and is experienced in all aspects of ex parte patent practice, including examiner interviews, third-party submissions, appeals, interferences, reexaminations, reissues, and inter partes reviews (IPR).  

Timothy also has significant and unique experiences in collaborating with non-U.S. patent counsel in opposition and invalidation proceedings before the European Patent Office, the Chinese Patent Office and the Japanese Patent Office.

Background & Credentials


  • University of Toledo (B.S., Chemical Engineering, 1989)
  • University of Toledo (J.D., cum laude, 1992)


  • South Carolina
  • Ohio
  • U.S. Patent and Trademark Office

Professional Activities

  • American Bar Association
  • Carolina Patent, Trademark & Copyright Law Association


  • Order of the Coif
  • American Jurisprudence Awards

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