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David K.S. Cornwell

David K.S. Cornwell

David K.S. Cornwell is a director in Sterne Kessler's Mechanical & Design Practice Group and is highly respected for his knowledge of design patents and mechanical devices.

David specializes in patent litigation in the fields of consumer product protection, clean energy and clean technology, biotechnology, computers and related technologies.  He has numerous offensive and defensive litigations to his credit in the fields of utility patents, design patents, trade dress, unfair competition, and trade secret law, and is known for his creative litigation strategies.  He has been named counsel in numerous post-grant proceedings including over 90 inter partes reviews and 4 derivation proceedings. David has been lead counsel in over 60 patent cases and has been lead trial counsel in numerous Markman hearings and other evidentiary proceedings.  He has experience before the US International Trade Commission, and has been the lead attorney before the Board of Patent Appeals and Interference in complex patent interference proceedings.  He has also served as an expert witness in matters focused on design patents and inequitable conduct.   He is viewed as a trusted advisor to Fortune 1000 companies headquartered around the world. 

Prior to joining the firm in 1987, David was associate patent counsel for the University of California at Los Alamos National Laboratory, and worked as a patent examiner in the field of missile guidance systems.  In law school, he worked as a graduate research assistant for the University of California in the field of geothermal fluid mechanics.  He also performed complex three dimensional computer modeling of heat transfer systems.

David has served as a claim drafting instructor for the advanced Patent Application writing workshop sponsored by the Patent Resources Group.  He was a member of the Advisory Board to the University of New Mexico-Los Alamos, the board charged with approving the budget and shaping University policy for UNM-LA.

Additionally, David is a contributing author of Patent Office Litigation, Second Edition, published in 2017, the book provides a fresh and comprehensive exploration of patent office litigation proceedings, including how the proceedings interact with other aspects of patent procurement and enforcement, while delivering practical analysis and advice. This second edition of Patent Office Litigation is the follow up to the first version of the book that was published in 2012 by Thomson Reuters Westlaw that focused on the contested proceedings that were introduced under the America Invents Act that year.

David earned his J.D. and his B.S., in mechanical engineering, from the University of New Mexico.


  • The Legal 500, "Highly Recommended Lawyer - Patent Prosecution (including reexamination and post-grant proceedings)" (2017)
  • Chambers & Partners USA, "Leading Lawyer in Intellectual Property" (2017-2008)
  • LMG Life Sciences, "Life Sciences Star" (2016 - 2012)
  • Cleantech Group, "Global Cleantech 100" (2013)
  • The Legal 500, "Leading Lawyer in Intellectual Property" (2008)

Representative Matters

  • Ole K. Nilssen and Geo Foundation v. Osram Sylvania – Represented Osram Sylvania in a patent infringement case.  Eleven of plaintiff's patents were found unenforceable and attorney fees were awarded for our client. 
  • Stutz Motor Car Company v. Reebok International Ltd. – Reebok was sued for patent infringement and trade secret misappropriation.  The accused product was the successful The Pump™ technology.  Successfully defended Reebok winning both the patent infringement and trade secret case on summary judgment. 
  • Payless Shoe Source v. Reebok International Ltd. – Payless filed a declaration judgment action against our client, Reebok.  Reebok counterclaimed for patent infringement, trade dress infringement, and trademark infringement.  Reebok successfully prosecuted this case and helped establish the legal principle of "post sale confusion."
  • Reebok International Ltd v. J. Baker – In this case, we prosecuted a design patent infringement case on behalf of Reebok.  This case is significant because Reebok successfully obtained an injunction pending appeal after the lower court denied a motion for preliminary relief. 
  • Hockerson-Halberstadt, Inc. v. Avia Group – In this case, we successfully defended a $100 million claim of patent infringement.  The Federal Circuit affirmed the lower court's finding of non-infringement.
  • Tailored Lighting, Inc. v. Osram Sylvania Products, Inc.(W.D.N.Y.) -- lead counsel representing Sylvania in defense of a patent lawsuit involving aftermarket automotive headlamps.  In this case, the Court granted summary judgment of non-infringement and invalidity in favor of Sylvania.

Thought Leadership

Contact Information

Phone Number


University of New Mexico School of Law
Mechanical Engineering
University of New Mexico


District of Columbia Court of Appeals
New Mexico
Supreme Court of the United States
U.S. Court of Appeals for the Federal Circuit
U.S. District Court for the Central District of Illinois
U.S. District Court for the Southern District of Ohio
United States Patent & Trademark Office


  • Clean Tech Law & Business, Advisory Board Member