John T. Duffey

John T. Duffey is a Partner at Maslon LLP and Co-Chair of the firm’s Business Litigation Group. He represents clients in complex commercial lawsuits and disputes, with particular emphasis on noncompete, trade secret, product liability, and corporate trust matters. He handles litigation in federal and state courts, arbitration, and mediation. His work spans every stage of a dispute, including early case assessment, discovery, injunction proceedings, trial preparation, and post-trial issues.

John earned his B.A. in History from Duke University and his J.D., cum laude, from the University of Michigan Law School. During law school, he served as editor-in-chief of the University of Michigan Journal of Law Reform and received the Jeffrey S. Lehman Legal Practice Award and the Sarah Honigman Memorial Award. He is admitted in Minnesota and before the US District Courts for Minnesota and the Eastern District of Michigan.

John has represented large and small businesses in a range of high-stakes disputes. His experience includes enforcing noncompete and restrictive covenant agreements, handling trade secret claims, defending breach of contract and fiduciary duty actions, and representing a national banking association in litigation and bankruptcy matters involving indenture trustee responsibilities. He has also managed e-discovery issues in numerous state and federal court cases, bringing a practical approach to complex commercial litigation.

John T. Duffey is active in professional and community service through the Minnesota State Bar Association and Hennepin County Bar Association. He also volunteers as a coach with Maslon UPLIFT: Legal Institute for Teens. Through his legal services, he combines courtroom advocacy, strategic litigation planning, and experience with restrictive covenants, corporate trust disputes, and other commercial matters. His practice reflects a focus on helping businesses navigate complex litigation efficiently and with clear strategic direction.

Law Office Affiliations

• Partner, Maslon LLP
• Member, Minnesota State Bar Association
• Member, Hennepin County Bar Association

Licensed State

• Minnesota

Education

• University of Michigan Law School
  Juris Doctor (JD)
• Duke University
  Bachelor of Arts (BA)

Awards & Badges