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John S. Paniaguas

Of Counsel
fax +1 312.985.5576

John S. Paniaguas assists technology companies with domestic and international strategic intellectual property planning including domestic and international patent preparation and patent prosecution, patent portfolio management and patent licensing.

He has extensive experience in business method patents, novelty and non-infringement analysis, reissues, ex parte re-exams, ex parte appeals before the Patent Trial and Appeal Board (PTAB) and due diligence of domestic and international patents and applications associated with mergers and acquisitions of target companies. He represents both privately held and publicly traded companies, including start-ups. Mr. Paniaguas has handled inter party reviews before the PTAB and appeals from the PTAB to the Court of Appeals for the Federal Circuit.

A former electrical engineer, John has extensive experience with numerous forms of technology, including electronic circuits and devices, semiconductor fabrication, ion implant devices, automotive sensors, application specific integrated circuits, computer systems, telecommunications systems, software, optical components, optical systems, electronic communications systems, optical communications systems, lasers, laser weapon systems, battery chargers, avionics, electrical high-voltage equipment, electrical circuit breakers, fossil and nuclear energy generation equipment, mechanical components and systems, complex mechanical systems, oxy-fuel combustion systems and electro-mechanical systems.

As a member of the adjunct faculty at the DePaul University College of Law for over 18 years, John teaches Advanced Patent Law and has taught Introductory Patent Law in the past. John is also a member of the adjunct faculty at John Marshall Law School for two years where he teaches Intellectual Property Licensing. John is the Chairman emeritus of the Center for Intellectual Property Law and Information Technology at DePaul College of Law.

He has a strong commitment to pro bono work and was honored in 2004 with a Pro Bono Service Award at Katten Muchin Rosenman LLP for patent law work performed on behalf of inventors and artists.

John is a licensed professional engineer in Illinois and Indiana and worked as an Electrical Engineer for over 10 years at Sargent & Lundy engineers and Northern Indiana Public Service Company with a focus on the electrical design of nuclear and fossil generating stations and high-voltage electrical substations. John has extensive experience in licensing of nuclear generating stations before the Nuclear Regulatory Commission and has training as a nuclear reactor operator.

He formerly served as in-house patent counsel for the McGraw Edison Company and for Motorola and was a partner in the patent specialty firms of Fitch, Even, Tabin & Flannery and Mason, Kolehmainen, Rathburn & Wyss. John is a former partner in the Intellectual Property Department of Katten Muchin Rosenman LLP, where he worked for over 14 years.


J.D., DePaul University College of Law, Chicago, Illinois
B.S.E., Purdue University-Calumet Campus, Hammond, Indiana


Martindale-Hubbell AV Preeminent Top-Rated Lawyer in Intellectual Property Law (2012-2013)

Named a Leading Lawyer in Chicago by Leading Lawyers℠ (2004-2024)


DePaul University College of Law Center for Intellectual Property and Information Technology, Advisory Board, Chair emeritus

Institute of Electrical and Electronics Engineers, Life Member

Knights of Columbus, Treasurer

Lake County Bar Association (Indiana), Board of Managers

Intellectual Property Law Association of Chicago (IPLAC), Chair, International Patent Law Committee

State Bar Licenses

Illinois, Indiana

Court Admissions

U.S. Supreme Court
U.S. Court of Appeals, 7th Circuit
U.S. Court of Appeals, Federal Circuit
U.S. District Ct., N.D. of Illinois
U.S. Patent and Trademark Office


  • Author, “Ownership and Management of Patent Rights” chapter of “Illinois Property Law” Handbook, Illinois Institute of Continuing Legal Education, 2017 edition.
  • Co-Author, “Guidance on Software Patents from the U.S. Supreme Court in Alice Corporation v. CLS Bank International” Clark Hill Trend Watch 2014
  • Author, “Investigating the Concept of Novelty in the America Invents Act,” pages 119-131, Developing a Patent Strategy (Aspatore 2012)
  • Author, “A Practitioner’s Guide to Protecting Intellectual Property Assets,” DePaul Journal of Art, Technology & Intellectual Property Law, Vol. 20, No. 2, pages 279-325 (Spring 2010)
  • Author, “John S. Paniaguas on the Patentability of Tax Strategies and the Return to State Street Bank & Trust v. Signature Financial Group,” LexisNexis Patent Law Center (January 28, 2008)



  • Speaker, “Coping with the New First-Inventor-to-File Prior Art Law: What Patent Prosecutors Need to Know and Do Before and After the Effective Date,” IPLAC (January 25, 2013)
  • Moderator, “International Perspectives on the America Invents Act,” IPLAC (March 21, 2012)
  • Moderator, “The Impact of the America Invents Act,” Chicago Daily Law Bulletin’s 7th Annual Corporate Intellectual Property Law Conference (February 2012)
  • Panelist, “Patent Wars: Roundtable on Defensive Patenting in the Wireless Technology Industry,” IIT Chicago-Kent College of Law (November 2, 2011)
  • Speaker, “America Invents Act: Patent Reform” 2011 IPLAC (October 11, 2011)