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Russell E. Cass

Senior Counsel


130 E. Randolph St.
Suite 3900
Chicago, IL 60601
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Fax: 312.517.7591
J.D., With high honors, George Washington University Law School, Washington DC, 1994, Order of the Coif and George Washington Law Review
B.S., University of California-Los Angeles (UCLA), Los Angeles, California, 1990
State Bar Licenses
New York
Court Admissions
U.S. Court of Appeals, Federal Circuit
U.S. District Ct., N.D. of Florida
U.S. District Ct., N.D. of Illinois
U.S. Patent and Trademark Office

Russell E. Cass

Senior Counsel

Russell E. Cass is an intellectual property lawyer with over 20 years of experience representing clients in a broad range of patent and other IP matters.  Russ has extensive experience litigating patent infringement matters, including trying cases before judges and juries in Federal District Court, handling appeals before the Court of Appeals for the Federal Circuit, litigating proceedings before the Patent Trial & Appeal Board, and handling disputes before arbitration panels.  Russ’s IP practice also encompasses counseling, non-infringement and validity opinions, due diligence investigations, freedom-to-operate analyses, patent portfolio management, and trademark litigation. 

Russ has a degree in electrical engineering, and has worked on diverse technologies including electronics, medical devices, computer hardware and software, automotive devices and systems, pharmaceuticals, and biotechnology.   His clients have ranged from startups to some of the world’s largest technology and healthcare companies.

Russ’s representations include:

  • As trial counsel in a patent infringement case, winning a $95 million jury verdict for a manufacturer of high-efficiency power converters against eleven of its largest competitors, and successfully defending the verdict across-the-board in the Court of Appeals.
  • As trial counsel, successfully defending a Fortune 500 global healthcare company in a patent infringement action by obtaining a judgment of noninfringement after a week-long trial, and then securing an additional ruling of invalidity on appeal.
  • Successfully defending a Fortune 100 software company in a patent infringement action by obtaining a dismissal of the action on non-infringement grounds, and successfully defending it on appeal.
  • Successfully defending clients in actions brought by the world’s largest patent assertion entity, in a variety of tribunals, including Delaware, Pennsylvania, Texas, and the PTAB.  

Russ is a frequent speaker and commentator.  His presentations have ranged from chairing a panel of Federal judges to presenting on patent law and federal litigation topics before both specialist and generalist audiences.  He is active in bar associations and serves on the Executive Board of the Linn American Inn of Court.  Before joining Clark Hill, Russ spent fifteen years as a partner in the intellectual property group at the firm of Sidley Austin LLP.

Russ is active in community and pro bono legal organizations providing representation to the most vulnerable members of society.  He serves on the Leadership Board of Heartland Alliance’s National Immigrant Justice Center, which provides pro bono direct legal services to refugees fleeing persecution, and has handled cases for refugees from countries including Rwanda, Congo, Eritrea, Lebanon and Honduras.



  • Moderator, “Taking Another Bite at the Apple: Multiple Proceedings Before the PTAB,” featuring PTAB Chief Judge David Ruschke, Federal Circuit Bar Association, October, 2017.
  • Moderator, “Hot Topics in Patent Law: IPRs and Venue,” ABA IP Litigation Roundtable, October, 2017.  
  • Panelist, “Cases to Watch Panel – PTAB Proceedings,” Federal Circuit Bar Association Intellectual Property Law Symposium, March 2017.
  • Panelist, “From Chevron to Cuozzo: Practical Impacts of Administrative Law on PTO Proceedings,” Federal Circuit Bar Association Webinar, March, 2017.
  • Presenter, “Five IP Mistakes Startups Make,” 1871 Center for Technology & Entrepreneurship, January 2017.
  • Moderator and Chair, “2016 Federal Judges’ Panel,” Richard Linn Inn of Court, March 2016.
  • Chair and Presenter, “Trial of the Jury Trial,” Jury Trial Simulation Featuring Judges Richard Posner, Rebecca Pallmeyer, and Matthew Kennelly, Joint Meeting of Chicago Inn of Court and Richard Linn Inn of Court, April 2015.


  • “Royalty Bases and Damages Theories: A Federal Circuit Update,” Law360 (April 7, 2016)
  • “A Look At 2014 Federal Circuit Cases Impacting AIA Proceedings,” Law360 (December 16, 2014)
  • “The Fee-Shifting Climate After Octane And Highmark,” Law360 (August 28, 2014)
  • “High Court May Provide New Approach To ‘Patent Trolls’,” Law360 (December 3, 2013)