Brian Byrne’s practice focuses on the antitrust review of mergers and acquisitions, criminal antitrust investigations and other enforcement matters, and civil antitrust litigation.

Brian joined the firm in 1995 and became a partner in 2004. Resident in the firm’s Brussels office from 2008 to 2011, he offers clients seamless counsel on cross-border matters and has been deeply involved in transactional and enforcement matters in both the U.S. and Europe and many other jurisdictions.

Notable Experiences

Merger Highlights

  • Synopsys in its pending $35 billion acquisition of Ansys.

  • Figma in U.S. antitrust review of proposed acquisition by Adobe.

  • Applied Materials on antitrust aspects of numerous acquisitions and related advice.

  • Family Dollar in its $9.3 billion acquisition by Dollar Tree and the related hostile tender offer by Dollar General.

  • Molson Coors in its $12 billion acquisition of SABMiller’s interest in their U.S. joint venture, MillerCoors (and also in connection with AB InBev’s $100 billion acquisition of SABMiller); previously advised Molson Coors in the creation of the MillerCoors joint venture with SABMiller.

  • Johnson Controls in various transactions, including its $870 million acquisition of Silent-Aire, a leader in cooling equipment and modular data centers for hyperscale cloud and co-location providers.

  • Lenovo in various transactions, including its $2.3 billion acquisition of IBM’s x86 server business.

  • Samsonite in its $1.8 billion acquisition of Tumi.

  • Air Liquide in its $13.4 billion acquisition of Airgas, creating the world’s largest supplier of industrial gases.

  • Maytag in its acquisition by Whirlpool, and Whirlpool in numerous subsequent matters, including its acquisition of a controlling stake in Indesit.

  • Sysco in its acquisition of Greco & Sons.

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Antitrust Litigation and Enforcement Highlights

  • Swedish Match in successful defense of monopolization claim based on alleged sham litigation in C.D. Cal.

  • Iowa Premium in class action litigation in D. Colo. related to allegations of wage fixing in the red meat industry.

  • A leading global semiconductor industry supplier, in connection with monopolization/dominance investigations around the globe.

  • Walgreens, in defense of a class action antitrust case in the generic pharmaceuticals antitrust litigation.

  • Whirlpool and Brazilian subsidiary Embraco in global cartel investigations in the refrigeration compressor industry, and in related U.S. class actions and other antitrust litigation, including a successful Sixth Circuit appeal.

  • Valeo in cartel investigations by the DOJ, European Commission, and other antitrust authorities into possible price fixing in the automotive parts industry, as well as in related U.S. class action litigation.

  • HSBC in investigations by antitrust and other authorities in the U.S., Europe and Asia concerning foreign exchange (FX) trading.

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Contributed to various publications on developments in antitrust laws, including the Global Competition Review, Competition Law Insight, ABA’s Annual Review of Antitrust Law Developments and the ABA’s Antitrust Law Developments.


  • May 10, 2023
    Informa Connect West Coast Conference
  • May 12, 2022
    Antitrust West Coast 2022
  • September 24, 2019
    Knect365 Law Antitrust TX 2019
  • February 22, 2017
    ABA Corporate Counseling Monthly Update
  • October 1, 2015
    ABA Section of Antitrust Law: Merger Practice Workshop
  • July 10, 2015
    What’s the Harm in it?  Empirical Methods in Competitive Effects Analysis of Mergers – La Jolla, California
  • June 6, 2013
    Antitrust in the Americas – The First Year Under Brazil’s New Law and the Challenges Ahead – Sao Paulo
  • October 18, 2012
    Developments in Corporate Criminal Investigations and Prosecutions – Chicago
  • May 30, 2012
    Leniency and the Prosecutor Agency’s Enforcement Techniques: Tools Against Collusion
  • April 12, 2012
    Managing Merger Control Risks in M&A Transactions, Under the New Competition Law: What to Expect in Brazil in Light of the US and European Experience
  • November 26, 2010
    16th International Antitrust Conference