Thomas J. Undlin



Thomas Undlin has experience in an array of complex business disputes including antitrust, breach-of-contract, fraud, securities, and intellectual property claims. He has practiced in a wide range of jurisdictions including state and federal courts in Minnesota, Wisconsin, Illinois, New York, Texas, and California, as well as varied sponsoring agencies for both domestic and international arbitration and dispute resolution. As co-lead counsel, Mr. Undlin played a key role in Kirk Dahl, et al. v. Bain Capital Partners, LLC et al., a class action suit against some of the world’s largest private equity firms for a conspiracy to suppress the buyout price for public companies, with total settlements of nearly $600 million. Mr. Undlin is also a co-lead counsel in In re Payment Card Interchange Fee and Merchant Discount Litigation, since its inception in 2005. Mr. Undlin and his team secured a $5.6 billion class settlement in the historic litigation in September 2018. The settlement, which was granted final approval in December 2019 and affirmed on appeal in March 2023, represents the largest settlement of a private antitrust action in the 130-year history of the Sherman Act.

According to Chambers, Mr. Undlin “is a first-class lawyer and wonderful adviser.”

In re Payment Card Interchange Fee and Merchant Discount Antitrust Litigation, MDL No. 1720 (E.D.N.Y.): Serving as court-appointed co-lead counsel, Robins Kaplan reached a $5.6 billion antitrust class action settlement on behalf of a class of more than 10 million U.S. merchants who accepted Visa and Mastercard credit and debit cards for the purchase of goods and services. Plaintiffs alleged that Visa and Mastercard, as well as major card-issuing banks such as JPMorgan Chase, Bank of America, Citibank, Wells Fargo, and Capital One, violated antitrust laws and charged merchants who accept credit and debit cards supra-competitive fees on card transactions. The settlement, which was granted final approval in December of 2019 and affirmed on appeal in March of 2023, represents the largest settlement of a private antitrust action in the 130-year history of the Sherman Act.

Kirk Dahl, et al. v. Bain Capital Partners, LLC et al., No. 07-cv-12388 (D. Mass.): Co-lead counsel representing public shareholders of target companies taken private in large leveraged buyouts in a class action suit against the largest private equity firms who allegedly conspired to suppress the acquisition prices for the target companies.

Omnicare, Inc. v. UnitedHealth Group, Inc.: Represented defendants UnitedHealth Group, Inc. and PacifiCare, Inc. in an antitrust lawsuit involving alleged price-fixing and fraud related to prescription drug reimbursement under the federal Medicare Part D program.  Plaintiff Omnicare sought damages exceeding $1 billion and permanent injunctive relief.  After summary judgment motion was argued in August 2008, the U.S. District Court granted summary judgment to defendants on all claims in January 2009.  Published decision:  Omnicare, Inc. v. UnitedHealth Group, Inc., 594 F. Supp. 2d 945 (N.D. Ill. 2009).  Summary judgment was subsequently affirmed. Omnicare, Inc. v. UnitedHealth Group, Inc., 629 F.3d 697 (7th Cir. 2011).

Powell Protection Systems, Inc. v. Best Buy Stores, L.P. (Dallas County, Texas):  Lead trial counsel in defense of action claiming interference with contract and fraud relating to a home audio/video/security wiring program (2007).

Game Financial Corporation v. Global Cash Access (Minnesota, Hennepin County): Lead plaintiff’s counsel in action for interference with contract and prospective business relations (June 2004).

Advanced Communication Design, Inc. v. Premier Retail Networks, Inc. (Case No. 01-1271, 1272, United States Court of Appeals for the Federal Circuit): Defense counsel in action leading to reversal of default judgment and order for preliminary injunction in patent infringement action (September, 2002).

Racal NCS, Inc. v. Alliant Techsystems Inc., The Raytheon Group, Hughes Aircraft Company (Miami, Florida) (AAA International Centre for Dispute Resolution): Defense trial counsel before an international tribunal in a contract dispute relating to an underwater sonar device (December, 2002). v. Melvin Masters (Minnesota, Hennepin County): Lead litigation counsel in shareholder derivative action and related proxy battle (March, 2002).

Carlson Hospitality Group, Inc. v. Diversey Lever, Inc. (Minnesota, Hennepin County): Lead counsel in dispute over vendor supply agreement (October, 2002).

Lockheed Martin Environmental Systems v. Alliant Techsystems Inc. (California, Los Angeles County): Lead trial counsel for defendant in action claiming breach of contract and changed conditions relating to environmental clean-up project at China Lake Naval Weapons Base (August, 1999).

Mission Technologies v. Alliant Techsystems Inc. (Texas, Federal Court): Lead defense counsel in matter claiming theft of trade secrets and breach of contract relating to unmanned aerial vehicle (1999).

Peterson v. Fluegel (Minnesota, Dakota County): Plaintiffs’ trial counsel in professional negligence action (January, 1999).

Metropolitan Life Ins. Co. v. Golden Triangle (Minnesota, Federal Court) (121 F.3d 351 (8th Cir. 1997)): Trial counsel in defense of claims for fraud and breach-of-contract relating to commercial property sales to a real estate investment trust.

KPMG-Piper Fund Litigation (Minnesota, Federal Court): Defense counsel in securities and accounting fraud class action (1995).

Chambers USA
Benchmark Litigation Star 2022
  • The Best Lawyers in America: Litigation - Intellectual Property (2023-2024 editions)
  • Benchmark Litigation: Litigation Star (2020-2024 Editions)
  • Chambers USA: Antitrust, Minnesota (2022-2024)
Bar Admissions
  • Minnesota
  • U.S. District Court, Minnesota
  • U.S. Court of Appeals, Second Circuit
  • U.S. Court of Appeals, Eighth Circuit
  • U.S. Court of Appeals, Federal Circuit
  • U.S. Supreme Court
  • William Mitchell College of Law, J.D., cum laude (1987)
  • St. Olaf College, B.A., Political Science
Professional Associations
  • American Bar Association (Litigation Section)
  • Minnesota State Bar Association 
  • Hennepin County Bar Association
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