Mary G. Kaiser

Partner | Washington, D.C. | (202) 887-6952
(202) 887-6952

Mary Kaiser is a partner in Morrison & Foerster’s Global Antitrust Law Practice. Mary represents domestic and multinational companies as both plaintiffs and defendants in in all aspects of antitrust and competition-related matters, including internal and government antitrust investigations, enforcement proceedings, and class action litigation in federal and state courts. She has defended companies in antitrust and related complex litigation involving claims of price-fixing, monopolization, and refusals to deal, as well as prosecuted antitrust counterclaims in patent and IP infringement matters. Mary also has experience counseling clients on antitrust compliance and merger advice. Her clients span various sectors from media to life sciences to computer software.

Mary also maintains an active pro bono practice, with experience representing clients in voting rights, asylum, and landlord-tenant matters.

Prior to joining Morrison & Foerster, Mary clerked for the Honorable Marian Blank Horn of the U.S. Court of Federal Claims and handled complex commercial litigation matters at another global law firm.

Representative matters include:
  • Defending the largest broadcast television station operator in the United States in a putative class action alleging price-fixing of television advertising in multiple markets nationwide.
  • Providing general antitrust counseling to The Clorox Company.
  • Defended a Japanese manufacturing client in a consolidated class action litigation alleging federal and state antitrust claims related to an alleged price-fixing conspiracy, obtaining a favorable settlement during trial.
  • Represented Teradata Corp. in connection with its monopolization and tying claims against SAP SE relating to the market for Enterprise Data Analytics and Warehousing.
  • Represented a national property management software provider in a lawsuit claiming federal antitrust and state law tort claims against its competitor, obtaining a favorable settlement after jury selection.
  • Represented a leading multinational semiconductor manufacturing firm as a third party seeking to block the merger of two key suppliers.
  • Defended Deere & Company in the U.S. Department of Justice litigation relating to its proposed acquisition of Precision Planting LLC's equipment business.
  • Represented a global auto parts manufacturer in defense of multi-district class actions that resulted from the U.S. Department of Justice's largest ever criminal investigation, involving allegations of price-fixing for certain auto parts.
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