Sandra A. Frantzen Shareholder


Sandra Frantzen practices a broad range of intellectual property law focusing on patent, trademark and copyright litigation, and client counseling. Recognized in the Law Bulletin’s list of “40 Illinois Attorneys Under 40,” Sandra has extensive litigation and consulting experience in various industries but has particular expertise in the medical device, pharmaceutical, chemical and biotechnology industries.

Ms. Frantzen is a trial attorney and litigator who focuses on assisting clients with resolving worldwide intellectual property disputes. Serving as lead trial counsel on behalf of a wide range of clients including both start-up and Fortune 500 companies, Ms. Frantzen’s work for clients has ranged from small cases to cases involving damages in the hundreds of millions.  Ms. Frantzen participates in all aspects of dispute resolution from pre-litigation consultation to trial and appellate work.  Her work includes assessing and reviewing the legal issues surrounding clients’ technologies, formulating litigation and dispute resolution strategy, appearing and arguing in court, preparing for and participating in jury trials and arbitration proceedings, spearheading mediation and settlement sessions, and working with witnesses and experts. Ms. Frantzen has appeared on behalf of clients in federal courts throughout the country and has also managed worldwide litigations alongside OUS counsel. One client from an international biotechnology company stated, “Sandra was absolutely instrumental in the successful defense and resolution of this case that was, quite literally, ‘bet-the-company’ litigation. This experience led my company to work with Sandra on multiple other matters, and she has never failed to deliver. Having worked with and against some of the best lawyers our profession has to offer, I can unequivocally say that Sandra is among the elite of the elite. As a client and as a professional colleague, this is one lawyer that I definitely want on my side of the table.”

A member of the Patent Bar and registered to practice before the U.S. Patent Office, Ms. Frantzen is well-versed in handling proceedings with the U.S. Patent Office and has been lead counsel in several inter partes review proceedings. Recently, Ms. Frantzen received four favorable Final Written Decisions by the Patent Trial and Appeal Board after a full trial on the merits.

Ms. Frantzen also regularly advises clients on strategic IP development, acquisition, protection and enforcement with a focus on value. Among other things, she has experience evaluating patents and patent portfolios, drafting and negotiating license and manufacturing agreements, consulting regarding licensing matters, performing due diligence review and analysis of intellectual property rights for corporate acquisitions and mergers, and assisting clients in obtaining patents, copyright, and trademark registrations. Ms. Frantzen has also served as lead IP counsel assisting clients in corporate acquisitions.

Ms. Frantzen graduated from Iowa State University with high distinction with B.S. degrees in Chemistry and Environmental Science, and received her law degree from The University of Chicago Law School in 1999, where she also graduated with honors.


  • University of Chicago, J.D., with honors, 1999
  • Iowa State University, B.S. Chemistry, B.S. Environmental Science, with highest distinction, 1996


  • Illinois
  • U.S. District Court for the Northern District of Illinois (including Trial Bar)
  • U.S. Court of Appeals for the Federal Circuit
  • U.S. Patent and Trademark Office