Mary G. Kaiser

Mary G. Kaiser
Washington, DC
+1 202 346 4036

Mary Kaiser is a partner in Goodwin’s Antitrust & Competition practice and a member of the firm’s Complex Litigation & Dispute Resolution group. Mary represents domestic and multinational companies as both plaintiffs and defendants in antitrust and competition-related matters, including federal and state court proceedings, arbitrations, and government antitrust enforcement proceedings.

Mary has represented companies in antitrust and related complex litigation involving claims of price-fixing, monopolization, group boycotts, tying, and refusals to deal; she has also prosecuted and defended against antitrust counterclaims in patent and IP infringement matters. Mary has experience counseling clients on antitrust issues related to pricing strategies, MAP policies, and Robinson-Patman Act compliance. Her clients span various sectors, from media to computer software to consumer products.

Mary maintains an active pro bono practice and has represented clients in asylum, voting rights, landlord-tenant, and clemency matters.


  • Provi. Represented Provi, provider of a major B2B alcohol marketplace for commercial retailers to order alcohol products from distributors, in antitrust, unfair competition, and tort claims against two dominant alcohol distributors.*
  • Defended a global consumer products manufacturer against patent ambush antitrust claims brought by a competitor.*
  • Nexstar Media Group. Defended 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.*
  • Cedar AI. Represented a technology startup company in monopolization, refusal to deal, tortious interference, and unfair competition federal and state counterclaims.*
  • Provided general antitrust counseling to a global manufacturer and marketer of consumer and professional products.*
  • Matsuo Electric. 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.*
  • Teradata Corp. Represented Teradata Corp., a multi-cloud data platform, in connection with its monopolization and trying claims against SAP SE relating to the market for Enterprise Data Analytics and Warehousing.*
  • Entrata. 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.*
  • Deere & Company. Defended Deere & Company, a major manufacturer of agricultural and construction machinery, in the U.S. Department of Justice litigation relating to its proposed acquisition of Precision Planting LLC’s equipment business.*
  • Sumitomo Electric. 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.*

*Denotes experience prior to joining Goodwin

Professional Experience

Prior to joining Goodwin, Mary was a partner at Morrison Foerster in the firm’s Global Antitrust Law practice. Previously, she 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.

Professional Activities

Mary is an active member of the American Bar Association Antitrust Law section.




University of California, Berkeley, School of Law

(editor, Berkeley Journal of International Law; co-president, Berkeley Law Foundation)


University of Virginia


U.S. Court of Federal Claims, Hon. Marian Blank Horn



  • District of Columbia
  • California

Recognition & Awards

  • Litigator to Note: Civil Litigation/Class Actions: Defense, The Legal 500 (2024)
  • DC Rising Star, The National Law Journal (2023)
  • Recommended for Antitrust: Civil Litigation/Class Actions: Defense, The Legal 500 US (2023)
  • Ones to Watch, Best Lawyers (2023)
  • Ones to Watch in America: Commercial Litigation, Best Lawyers (2023)
  • Top 50 Women Leaders in Law, Women We Admire (2022, 2023)


Prior to law school, Mary was a staff writer for, covering the 2008 election cycle and appearing on MSNBC to discuss campaign advertising.