Darren S. Cahr concentrates his practice on intellectual property and advertising law, helping clients develop, protect, and defend their most critical intangible rights, marketing practices, and competitive positioning.  Darren has built a national reputation as a valued courtroom advocate, boardroom counselor, thought leader, and everyday advisor on cutting edge intellectual property issues, branding, false and comparative advertising, corporate identity, consumer promotions, and the legal implications of social media and new technology.

Darren heads the Firm’s Advertising and Intellectual Property Practice, where he counsels clients on the strategic protection of intellectual property rights, advertising and marketing practices, brand selection, state and federal consumer protection regulation, copyright and creative content, sweepstakes, contests and sales promotions, licensing, IP transactions, regulatory compliance, trade secrets, unfair competition and false advertising. Darren has litigated and tried a wide variety of sophisticated intellectual property and advertising disputes both in courts throughout the nation and before the International Trade Commission, the National Advertising Division, and Trademark Trial and Appeal Board.

Darren was recently awarded a ranking of “Lawyer of the Year” for Trademark Law in Chicago for 2022 in a peer review survey conducted by Best Lawyers® — a distinction awarded to only one attorney with the highest overall feedback for a specific practice area in each geographic location.  For nearly a decade Darren has been recognized each year in World Trademark Review magazine in its listing of the world’s leading trademark professionals, with past reviews lauding his ability to deliver “smart, thorough and fast” counsel to clients and noting that he is a “nationwide thought leader on the interface between social media and intellectual property.” Darren is “AV Preeminent” peer review rated by Martindale-Hubbell, reflecting the highest peer recognition for both ethical standards and legal ability, and has been repeatedly recognized as an “IP Star” by Managing Intellectual Property Magazine.

Darren is a widely published author on topics of law, technology, social media and popular culture, an active member of professional organizations, a science fiction novelist, a painter, and a musician. His highly praised presentations on the intersection of legal ethics and social media have been featured by several major bar associations at their annual meetings. He also regularly speaks on issues involving new media and intellectual property throughout the country and around the world, and can be found on Twitter @legallysocial.

Darren received his B.A. from Northwestern University and his J.D. from the Northwestern University Pritzker School of Law.


Representative Matters:

  • Represented major nutritional supplement company in large scale trademark infringement and false advertising litigation
  • Led grey market enforcement effort on behalf of global oral health product manufacturer
  • Successfully defended complex infringement action before the International Trade Commission, after full hearing on the merits, and review by the full Commission
  • Obtained summary judgment in defense of false advertising, false designation of origin, and trade secret claims, after extensive fact and expert discovery, including fee award
  • Successfully argued appeal before the Trademark Trial and Appeal Board, overruling trademark application refusal on novel specimen issue for significant life sciences company
  • Developed brand and IP strategies for global clients
  • Advised well-known food, retail, and consumer products companies on marketing practices and social media issues
  • Successfully represented major consumer products companies before nation’s premier advertising industry self-regulatory forums, National Advertising Division and Children’s Advertising Review Unit
  • Counseled major insurance companies on intellectual property issues and marketing practices
  • Negotiated trademark licensing transactions for significant consumer products companies and global retailers
  • Advised national retailer on copyright and trademark issues, and successfully resolved a series of high-profile infringement disputes pre-litigation
  • Coordinated international branding efforts with global network of foreign counsel for major life sciences company
  • Reviewed and cleared major comparative advertising campaign for well-known national restaurant chain
  • Counseled life-sciences companies on product packaging and legal risks emerging from parallel importation and counterfeiting
  • Reviewed and designed legal framework for cutting-edge online promotions, including sweepstakes, contests, and other marketing practices
  • Advised major toy and hobby company on copyright, trade secrets, and trademark issues

Professional Activities

  • International Trademark Association — Parallel Importation Committee

Publishing & Speaking

Representative Publications & Speaking Engagements

Recent Notable Speeches and Presentations:

  • Moderator, “Intellectual Property Trends to Watch in 2022 & Beyond,” SCG Legal Annual Meeting (September 2022)
  • Instructor, “The Metaverse: The Future of the Web and the Law Inside Your Head,” Continuing Legal Education Module (July 2022)
  • Speaker, “Trademarks and the Brain: Neuroscience and the Processing of Non-Literal Language,” Annual Meeting of the International Trademark Association Scholarship Symposium (January 2022) (with Sandra           M. Virtue, PhD)
  • Speaker, “Hot Topics in Advertising Law: Health and Wellness Claims,” National Advertising Division/BBB National Programs (March 2021)
  • Moderator, “What’s in a Name, Likeness and Image? The Prospect of a Federal Right of Publicity,” (December 2020)
  • Faculty, American Intellectual Property Law Association Design Rights Boot Camp (August 2019 and September 2020)
  • Speaker (General Session), “Social Media: Where is it Going, and Can We Ethically Get There?” International Trademark Association Annual Conference, Barcelona (May 2017)
  • Speaker, “Ethics in Social Media Controversies,” Intellectual Property Owners Association Annual Meeting, Chicago, IL (September 2015)

Selected Publications:

  • “Trademarks and the Brain: Neuroscience and the Processing of Non-Literal Language,” The Trademark Reporter, Vol. 112, Issue 4 (July-August 2022) (with Sandra M. Virtue, PhD)
  • “Important New Laws Will Have Ripple Effect for IP Owners, Practitioners,” Indiana Lawyer (April 2021) (with Lou Perry)
  • “How to Find and Protect Your Own Hidden Trademarks,” National Law Review (February 2021)
  • “Will New FTC Endorsement Guidelines Make a #Hashtag of Influencer Advertising?” National Law Review (March 2020)
  • “New U.S. Counsel Rule for Foreign TMs Promises Sea Change,” Law360 (July 2019) (with Melissa Dillenbeck)
  • “The Privacy Wars: Too Much, Too Little, or Too Late?” Bloomberg (May 23, 2019) (with Katherine Armstrong)
  • “Tech Brings Authentication Challenges in Ad and IP Cases,” Law360 (March 2019) (with Tore DeBella)
  • Contributing author, Telecommunications Law Answer Book, Practicing Law Institute (2014 – 2021) (chapter on social media)
  • Contributing author, Consumer Protection Law Developments, American Bar Association (2009)
  • Contributing author, Copyright Law and Policy in a Networked World, National Association of College and University Attorneys (2007)
  • “Of PACS and Trolls: How the Patent Wars May Be Coming to a Hospital Near You,” The Health Lawyer, Vol. 19, No. 1 (October 2006) (with Ira M. Kalina)
  • “False Advertising Claims: Proceedings at the NAD,” National Law Journal (January 1, 2006)
  • “March Madness: Dual Use Reverse Confusion and the First Amendment,” Selected Legal Papers, Vol. XVI, No. 1, American Intellectual Property Law Association, (April 1997)

Practice Areas

  • Intellectual Property & Advertising
  • Advertising & Marketing Practices
  • Trademarks & Branding
  • Copyright
  • New Media
  • Complex Litigation & Appeals
  • Sweepstakes & Promotions
  • Unfair Competition
  • Consumer Protection
  • Regulatory Compliance
  • Food
  • Children's Marketing
  • Life Science
  • Insurance Coverage


  • J.D. Northwestern University Pritzker School of Law 1993
  • B.A. Northwestern University 1990

Admissions and Qualifications

  • Illinois
  • U.S. Supreme Court
  • U.S. Court of Appeals for the Seventh Circuit
  • U.S Court of Appeals for the Ninth Circuit
  • U.S. Court of Appeals for the Federal Circuit
  • U.S. District Court for the Central District of Illinois
  • U.S. District Court for the Northern District of Illinois, Trial Bar

Prior Experience

  • Gardner Carton & Douglas LLP - Associate, Partner (1993-1998, 1999-2006)
  • Drinker Biddle & Reath LLP - Partner (2007-2019)
  • Faegre Drinker Biddle & Reath LLP - Partner (2020-2021)