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Ronan P. Harty


Ronan P. Harty

Antitrust & Competition
New York

Widely recognized as one of the leading antitrust lawyers in the United States. Focuses on M&A, joint ventures, business conduct issues and enforcement matters.

Consistently recognized for his antitrust work, Ronan advises clients in a wide variety of industries, including pharmaceuticals, financial services, defense, consumer goods, industrial products, retail and technology. His practice focuses on U.S. and cross-border M&A, joint ventures, all forms of business conduct issues and enforcement agency investigations.

He is ranked in Band 1 in New York by Chambers USA, which notes that he is a “preeminent antitrust lawyer…with a strong track record of securing merger clearance for multinationals engaged in cross-border transactions.”

Ronan has served in leadership positions in the antitrust community for many years. He is the editorial board chair of the American Bar Association’s flagship antitrust publication, Antitrust Law Developments (9th edition), and the editor of Global Competition Review’s Merger Remedies Guide – Third Edition. He is also on the editorial board of Antitrust Report.

Ronan serves on the board of Legal Services NYC.

Experience highlights

  • UBS in its proposed acquisition of Credit Suisse
  • JP Morgan Chase in its acquisition of First Republic Bank
  • Gilead Sciences in its $21 billion acquisition of Immunomedics
  • Charles Schwab in its acquisitions of USAA and TD Ameritrade
  • Hoffmann-La Roche in numerous acquisitions, including, most recently, its $4.5 billion acquisition of Spark Therapeutics
  • Ingersoll-Rand in the combination of its Industrial Division with Gardner Denver
  • Ferrero International in various acquisitions, including its acquisition of the Keebler business from Kellogg, and the acquisition of Nestle’s U.S. confectionary business
  • Services Group of America in its acquisition by U.S. Foods
  • Home Shopping Network in its acquisition by QVC
  • Syngenta in its acquisition by ChemChina
  • Advanced Semiconductor Engineering in its proposed acquisition of Silicon Industries Precision Co.
  • Syngenta in its defense of a takeover proposal by Monsanto
  • Emerson Electric in numerous acquisitions since 1986, including, most recently, its proposed $7.6 billion acquisition of National Instruments
  • Citigroup in its sale of its OneMain business to Springleaf
  • Tyson Foods in its acquisition of Hillshire Brands
  • Nippon Express in connection with the Department of Justice’s investigation of price-fixing in the freight forwarding business, and subsequent class action litigation 
  • Daiichi Sankyo in its sale of Ranbaxy
  • PricewaterhouseCoopers in its acquisition of Booz & Company
  • BATS Global Markets in its acquisition of Direct Edge
  • Maidenform Brands in its acquisition by Hanesbrands
  • H.J. Heinz in its acquisition by 3G Capital and Berkshire Hathaway
  • ConAgra in its acquisition of Ralcorp
  • Daikin Industries Ltd. in its acquisition of air conditioner manufacturer Goodman Global Inc.
  • National Express in its acquisition of Petermann Inc.
  • VF Corporation in its acquisition of Timberland
  • The Kingdom of Sweden in the sale of Absolut Vodka and other brands to Pernod Ricard
  • Gillette in its acquisition by Procter & Gamble
  • FirstGroup in its acquisition of the school bus services business of Laidlaw
  • CVS in its acquisitions of Eckerd Drugs, Revco, Arbor Drugs and its acquisition of Albertson’s freestanding drug stores
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The FTC non-compete rule



BTI Consulting Group – “Client Service All-Star,” 2023

Chambers Global – Competition/Antitrust

Chambers USA – Antitrust, New York, Band 1

Legal 500 U.S. – Antitrust: Merger Control, Hall of Fame

Who’s Who Legal – Competition

Burton Awards for Legal Achievement – “Distinguished Legal Writing Award,” 2013

Antitrust Writing Awards – “Best Academic Mergers Article,” 2013


LL.M., University of Michigan Law School
  • Cook Fellowship for Legal Research
B.C.L., University College Dublin
  • first-class honours

Professional history

  • Davis Polk since 1986
  • Assistant (Stagiaire) in the cabinet of Sir Leon Brittan, Vice President of the European Commission Responsible for Competition Policy, 1991

Qualifications and admissions

  • Brussels B-List
  • State of New York
  • U.S. District Court, E.D. New York
  • U.S. District Court, S.D. New York
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