Jeff Lillien was born and raised in Chicago and its surrounding suburbs, a region shaped by cultural diversity and vibrant communities. Growing up in a first-generation American household, he showed early talent in mathematics, which led to a natural interest in problem-solving. His upbringing also instilled a strong awareness of current events, government affairs, and financial matters. These influences inspired him to pursue a degree in Economics, combining his analytical skills with a desire to understand better how society functions.
Jeffrey's academic path led him to some of the nation’s most respected institutions. He started at the Massachusetts Institute of Technology (MIT), where he benefited from the mentorship of Dr. Louis Menand III. That mentorship helped shape his perspective on public policy and critical thinking. While at MIT, he strengthened his interest in using mathematics and technology to solve real-world challenges. He also immersed himself in foreign languages, becoming fluent in French while living in the French House (La Maison Française). Later, he earned a translator's certificate in commercial French from the Parisian Chamber of Commerce.
Continuing his education, Lillien attended New York University School of Law, where he was selected for the Law Review and served as an editor. He returned to Chicago for a year to study as a visiting student at Northwestern University School of Law. These experiences expanded his knowledge of legal foundations and deepened his understanding of how regulation intersects with commerce and technological development.
Jeffrey Lillien's professional direction was primarily shaped by the legal and financial challenges his family experienced, motivating him to enter the legal profession. He began his legal career at the Chicago office of Mayer Brown, a leading U.S. law firm. There, he developed expertise in complex legal matters, focusing on lending and securities law.
Jeff became essential to the evolution of financial products and commercial arrangements as his career progressed. He played a role in crafting innovative business structures and legal frameworks that help regulate market behavior and support financial innovation. His work has often focused on creating more efficient, transparent, and durable systems that bridge traditional financial markets with modern technologies. His legal work has primarily occurred between Chicago and New York City.
Throughout his legal career, Jeffrey has taken part in several initiatives designed to update and improve practices in financial markets. These contributions reflect both conceptual thinking and direct involvement. His notable projects include work on:
The Foreign Exchange Global Code, which promotes integrity and effectiveness in foreign exchange markets
U.S. Treasury Markets Best Practices, aimed at supporting transparency and proper conduct in treasury trading
A white paper on Digitization and Capital Markets, which explores how digital systems can improve market operations and proposes a framework for classifying digital assets
The Regulated Settlement Network, an initiative using distributed ledger technology to reduce settlement risk in fixed-income securities
Through these efforts, Lillien has addressed important issues, such as:
Establishing standards for ethical market conduct
Digitizing traditional financial instruments to make them more compatible with current systems
Using new technology to address settlement delays and risks
Developing systems to allow for continuous asset transfers and liquidity
These contributions have helped move traditional finance toward a model that reflects modern technological capabilities and global collaboration.
Jeff Lillien actively participates in several professional associations, reflecting his legal expertise and ongoing efforts to advance industry standards. These include:
International Swaps and Derivatives Association (ISDA)
Securities Industry and Financial Markets Association (SIFMA)
Global Financial Markets Association (GFMA)
Financial Markets Lawyers Group (FMLG)
In these roles, he has frequently spoken at events sponsored by central banks in the U.S., Europe, Japan, and the U.K., as well as at forums organized by the associations listed above.
Jeff has written and contributed to various white papers and articles on market reforms, digital transitions, and consistent regulatory approaches. His work has appeared in professional journals and policy discussions. His viewpoints have also been cited in media coverage and panel discussions, particularly those focused on the role of digital technology in updating financial systems. While links to these materials are forthcoming, they represent a substantial part of his ongoing thought leadership.
Jeffrey has devoted meaningful time to giving back to the communities that supported him and his family. This effort began during his college years at MIT, where he tutored middle-school students in math through Cambridge’s Tutoring Plus program—an organization valued by his mentor, Dr. Menand.
As an attorney, Lillien has contributed pro bono legal work, initially in human rights. He has served on the Midwest Immigrant Rights Center boards and the Heartland Alliance, where he co-chaired the Human Rights Council. Additionally, he has been involved with international human rights advisory boards at Northwestern University School of Law and DePaul University College of Law. More recently, he has focused his pro bono efforts on supporting New York’s artist community and advocating for disabled military veterans. His work in these areas has earned him several awards, which he considers highly meaningful.
He has financially supported charitable causes, particularly those related to education and the environment, continuing his broader commitment to community and public service.
In his personal life, Jeff Lillien prioritizes time with his child, with whom he shares a love of music and the arts. Their shared experiences go beyond recreation—they represent his dedication to nurturing creativity and emotional depth within his family.
Jeff maintains strong ties to his native city of Chicago, remaining a loyal fan of its sports teams and renowned pizza.
Lillien's lifelong service, education, and innovation journey define his work and contributions.