Photo of Todd S. Parkhurst

Todd S. Parkhurst

Of Counsel


  • Illinois
  • U.S. Supreme Court
  • Illinois Supreme Court
  • U.S. Patent and Trademark Office
  • U.S. Court of Appeals for the Federal Circuit
  • U.S. Court of Appeals for the Seventh Circuit
  • U.S. District Court for the Northern District of Illinois
  • U.S. District Court for the Northern District of Illinois – Trial Bar


J.D., University of Pennsylvania, 1966

B.S., University of Illinois at Urbana-Champaign, 1963


Todd Parkhurst has more than 40 years of experience in litigation, transactions and counseling in patent, trademark, copyright and trade secret law.

Todd has extensive experience litigating patent infringement and other intellectual property lawsuits. He has handled IP litigation involving computer software, video games, hand and machine tools, electronic lighting controls and numerous other devices. He also has handled copyright infringement lawsuits related to games, books, financial transactions software and illegal movie downloads.

In the area of trademark causes, Todd has registered hundreds of trademarks and prepared numerous use and infringement opinions. He is experienced in opposition, cancellation and concurrent-use proceedings. In addition, he has represented publishing companies in all phases of copyright and related matters and is experienced in copyright renewal issues.

Todd has prosecuted hundreds of patent applications and handled all subsequent solicitation activity in areas including hand tools, data processing software, railroad cars, pinball games, long distance pneumatic transfer systems, neutron generators, cryogenic particle sorting equipment and sophisticated machine tools, agricultural equipment and medical devices. He has also been responsible for all corresponding foreign patent prosecution. He is familiar with EPC and PCT prosecution and has authored numerous infringement opinions.

His counseling and transactions work has included complex license negotiations and preparation of patent, trade secret and know-how, trademark, and other licenses and agreements. He has also negotiated and prepared intellectual property transfers in a number of corporate acquisitions, mergers and divestitures.

Todd was previously a partner with Hughes Socol Piers Resnick & Dym, Ltd. He served consecutively as creator and head of the intellectual property practices in Chicago of Jenner & Block, Schiff Hardin and Holland & Knight LLP. 

Professional Affiliations

  • Illinois State Bar Association
  • Chicago Bar Association
  • American Intellectual Property Law Association of Chicago
  • Intellectual Property Law Association
  • Adjunct Professor, Intellectual Property Law, IIT Chicago-Kent College of Law
  • Instructor, Trade Secret Law
  • Instructor and creator, Intensive IP Trial Advocacy Course (first of its kind)
  • Arbitrator, American Arbitration Association (in cases involving technical engineering issues)
  • Mediator, Resolution Resources Corporation
  • Hearing Officer, Illinois Pollution Control Board

Community/Civic Activities

  • Chicago Literary Club
  • Director and Legal Counsel, Lifeline Pilots
  • Director and Legal Counsel, Illinois Society for Prevention of Blindness
  • Director, Legal Counsel and Member, St. Sebastian Players

Honors & Awards

Honors & Awards

  • Martindale-Hubbell AV Preeminent
  • Illinois Super Lawyers, 2005-06, 2008, 2012-16
  • Best Lawyers in America, 2005-07, 2013, 2018-2019
  • Best of U.S. IP Lawyers, 2007
  • Leading Lawyer — Illinois Leading Lawyers Network
  • Albert Nelson Marquis Lifetime Achievement Award


Representative Matters

  • Represented a leading radio-television network in trademark registration and use issues.
  • Represented Arco, a leading vacuum-bottle manufacturer in trademark revivification efforts.
  • Represented a large petroleum refiner in trademark disputes with ex-dealers.
  • Obtained injunctive relief for an important securities dealer that prohibited ex-employees from marketing computer software designed to assist in securities trading.
  • Handled licensing and patent acquisition activities including representation of an important video game and slot machine manufacturer, various software developers and users, and fluid distillation systems.
  • Prepared software production agreements and copyright and trade secret licenses on behalf of computer companies and represented small special-purpose computer companies in all intellectual property and contractual matters, as well as large businesses in the acquisition and licensing of software.

News & Insights

Seminars & Speaking Engagements

  • “Pleading for the Future,” a live theatrical presentation on Clarence Darrow’s defense of Leopold and Loeb
  • Presentation of Clarence Darrow’s speech titled “How to Pick a Jury”
    West Suburban Bar Association, May 12, 2012
  • “Murder on Lafayette Square,” a live theatrical presentation and video discussing the 1859 murder trial of Daniel Sickles, the first U.S. trial to successfully present a temporary insanity defense
    Illinois Institute of Continuing Legal Education and West Suburban Bar Association, 2011
  • “My Father’s Country,” a live theatrical presentation on the case of Minoru Yasui, who fought for the civil rights of Japanese Americans during World War II
  • “Information Disclosure Statements and the Duty to Disclose”
    American Intellectual Property Law Association Roadshow, 1995
  • “License Termination”
    Licensing Executives Society Annual Convention, 1993
  • “Copyright Issues for Libraries”
    Charleston Conference of the American Library Association, 1990
  • “Serial Pricing and Copyrights: Prophecies, Strategies and Fallacies”
    Charleston Conference of the American Library Association, 1989
  • “Adding to the Bottom Line Through Licensing”
    Licensing Executives Society Annual Convention, 1988


Articles & Books

  • “Unfair Competition,” 2013-2016 eds.
    Westlaw, Thompson Reuters, 2014
  • “Trade Secrets: Cases, Materials and Strategies,” (5th ed., 2008)
    (course book in use at Chicago Kent Law School)
  • “Procedures for Claim Construction After Markman”
    Mississippi College Law Review, 1999
  • “Free Ride or Fair Use: An Analysis of American Geophysical Union v. Texaco, Inc.”
    The Acquisitions Librarian, 1996

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