William Casey focuses his practice on patent, trade secret and other intellectual property litigation, as well as complex civil litigation. He also advises companies on acquiring, selling, evaluating, licensing and protecting intellectual property assets.

Mr. Casey’s representative litigation matters include:

  • ZeniMax Media, Inc. and id Software LLC in a successful enforcement of intellectual property rights resulting in a $500 million jury verdict;
  • SanDisk Corporation in a successful enforcement of a breach of patent license agreement resulting in a $28.5 million verdict;
  • Medtronic, Inc. as a defendant in a patent infringement suit in federal court and as petitioner in inter partes review proceedings involving endoluminal medical devices;
  • Justice Robert M. Mallano, individually and on behalf of a class of more than 3,000 California judges, justices and judicial pensioners, in a successful declaratory judgment action relating to the underpayment of judicial salaries; and
  • The National Football League in securing the dismissal of a putative class action filed by 10 retired NFL players alleging the NFL and its teams improperly provided prescription painkillers and anti-inflammatories to players.

His representative transactional matters include:

  • Cavium, Inc. in its pending $6 billion acquisition by Marvell Technology Group Ltd.;
  • Intel Corporation in its $15.3 billion acquisition of Mobileye, N.V.; and
  • Broadcom Corporation in its $37 billion sale to Avago Technologies Limited.  

Prior to joining Skadden, Mr. Casey served as an extern to the Hon. Charles R. Breyer of the United States District Court for the Northern District of California. He also served as an extern at the United States Patent and Trademark Office. Prior to law school, he worked as an engineer for several life sciences companies.

Mr. Casey maintains an active pro bono practice and serves on the board of the nonprofit organization Science is Elementary.



  • University of California, Hastings College of the Law (J.D., 2013) (magna cum laude, Hastings Law Journal)
  • Keck Graduate Institute (M.B.S., 2006)
  • Rose-Hulman Institute of Technology (B.S., Mechanical Engineering, 2004)


  • California
  • U.S. Patent and Trademark Office


Judicial Extern, Hon. Charles R. Breyer, United States District Court for the Northern District of California

William J. Casey

Associate, Intellectual Property Litigation