Margaret M. Duncan

USA: Illinois

McDermott Will & Emery
444 West Lake Street
Chicago, IL 60606-0029
United States

Tel: +1 312 984 6476


Margaret (Peg) M. Duncan focuses her practice on IP litigation, including patent, trademark and copyright litigation. Peg also focuses her practice on protection of intellectual property, including prosecution, counseling and transactions relating to global patent and trademark portfolios. Peg has represented numerous clients in federal courts and at the US Patent and Trademark Office in a wide variety of technologies and industries, including life sciences, chemical and computer hardware and software technologies, financial services, and food and beverage products.

From 2002 to 2014, Peg served as McDermott’s Chicago IP Practice Group Leader. Prior to joining McDermott in 1992, Peg also served as senior IP counsel for two fortune 100 companies.

Peg currently serves as president-elect of the Richard Linn American Inn of Court and serves on the International Trademark Association (INTA) International/US Amicus Committee. Peg also serves as vice chair of the Amicus Committee of the Intellectual Property Law Association of Chicago (IPLAC), for which she co-authored amicus briefs to the US Supreme Court in Alice Corporation v. CLS Bank International and SCA Hygiene v. First Quality Baby Products. She has been consistently recognized by Chambers USA, Best Lawyers, The Legal 500, IAM 1000, World Trademark Review and Illinois Super Lawyers.

Peg received her JD from Loyola University of Chicago School of Law, a BS in natural sciences from Xavier University and a BS in medical technology from Indiana University. Peg also served as a judicial extern for Chief Judge James B. Parsons in the US District Court for the Northern District of Illinois.

Intellectual property is not just many companies’ greatest asset—it is their greatest investment. Today, however, product lifecycles are short, competition is fierce, and reputations can be won or lost at the push of a social-media button. Further complicating the picture is an increasingly complex web of international laws and regulations, sweeping judicial decisions, and legislative initiatives that present constant challenges to businesses.

McDermott’s intellectual property practice helps clients identify and secure their creative assets, maximize the value of their IP portfolios, and enforce or defend their rights in courts and tribunals virtually everywhere their products are made, distributed and sold.

We counsel clients in all aspects of intellectual property, including copyrights, domain names, patents, trade secrets, trademarks and unfair competition. We provide end-to-end counsel on IP acquisitions, as well as employment, licensing, research, and vendor and outsourcing agreements and contracts. We also provide global representation for clients, with lawyers and IP professionals located across three continents and with team members who speak and write in English, Chinese, Farsi, German, Japanese, Korean and many other languages.

Our IP litigation team is unparalleled, with many of our litigators possessing extensive experience before US state and federal trial and appellate courts, the US Court of Appeals for the Federal Circuit, the US Supreme Court, the US International Trade Commission (ITC), the European Court of Justice (ECJ) and Court of First Instance (CFI), and courts throughout Europe.

With a diverse client base ranging from Fortune 500 companies to academic institutions and deep experience in life sciences, energy, media and telecommunications and other key markets, we are more than just IP counsel – we are a trusted partner providing pragmatic, results-driven solutions in response to real-world business challenges.

In the end, it’s all about quality. About an uncompromising commitment to legal excellence, extraordinary client service and a high-performance culture. About helping clients achieve stellar legal and business results—today, and well into the future.

We are an integrated, international law firm with recognized strength in tax, private equity, mergers and acquisitions, health care, high-stakes litigation, and many other key areas of transactional and regulatory law. We emphasize and foster long-term, industry-focused client relationships with multinational companies, rising entrepreneurial firms, investors and capital providers, and many of the world’s wealthiest families and individuals.

In word and deed, we value integrity, efficiency, diversity, and pro bono and community service.

“Excellent attorney” Margaret Duncan is widely respected as “not just great for clients and her firm, but also for the IP community in Chicago.” She provides expert representation on issues affecting clients in the financial services, hardware and software, and healthcare sectors.”
Chambers & Partners, 2017