William Shaffer is the Managing Partner for the firm's San Diego office. Mr. Shaffer focuses his practice on patent prosecution and counseling, patent portfolio building/management, patent analysis and post-grant patent procedures, including reexamination and reissue proceedings. He has been the lead or co-lead attorney for a dozen reexaminations, including both inter partes and ex parte matters, many of which involved patents in litigation, representing both patent owners and challengers.

Mr. Shaffer has assisted patent litigation efforts in jurisdictions including the Northern District of California, the Eastern District of Texas, the Eastern District of Virginia and the International Trade Commission. He has provided in depth analysis of individual patents and patent portfolios in connection with venture capital investments and corporate acquisitions and advised prominent venture capital backed start-ups. Specific technologies Mr. Shaffer has experience with include, among others, thin film processing, semiconductor manufacturing equipment, photovoltaic systems and films, chip-level packaging, computer generated imagery (CGI) animation, computer architecture, software- and Internet-based technologies and consumer products.

Prior to joining the legal profession, Mr. Shaffer was a software engineer for GTE Government Systems Corporation.

Mr. Shaffer was recognized as a Northern California "Super Lawyer" in the area of Intellectual Property by Super Lawyers magazine (2011-2017). Mr. Shaffer was recommended by Legal 500 US for Patent Prosecution (2012-2016). He was named an "IP Star" by Managing Intellectual Property magazine (2013-2017). Mr. Shaffer was recognized as a top patent practitioner by IAM Patent 1000 – The World’s Leading Patent Practitioners (2013-2017). He was named by Legal Media Group in its 2013 Guide to the World's Leading Patent Practitioners. Mr. Shaffer was listed as "Best of the Bar" in 2014 by the San Diego Business Journal.

Professional & Community Activities

American Bar Association

American Intellectual Property Law Association

San Francisco Intellectual Property Law Association


  • Southern Methodist University, J.D. (1992)
    Thompson Scholar, The International Lawyer, Articles Editor
  • Vanderbilt University, B.S., Electrical Engineering and Computer Science (1988)

Bar Admissions

  • California (1992)


  • U.S. Patent and Trademark Office (1993)

Who We Are

Suite 400, 12730 High Bluff Drive
San Diego, CA, 92130
t +1 858.350.6104
f +1 858.350.6111
1080 Marsh Road
Menlo Park, CA, 94025
t +1 650.324.6368
f +1 858.350.6111

William L. Shaffer

Experience Highlights

Reexamination Proceedings
Lead counsel successfully defended multiple reexaminations on a family of computer patents with concurrent litigation, enabling over $100 million in more