Lindsey Champlin, Vice Chair of the firm’s Global Antitrust & Competition Practice, counsels US and international companies on a range of antitrust issues, with a particular focus on securing antitrust clearances for all types of M&A transactions.

Drawing on her vast cross-border experience, Ms. Champlin assists leading companies on their most significant antitrust matters, such as:

  • Merger matters, including complex HSR filings and Second Request substantial compliance
  • Merger remedy negotiations
  • Merger litigation and arbitration
  • Conduct and consent decree compliance investigations

She represents clients doing business in diverse industries, from the energy and automotive sectors to industrial equipment and machinery, retail, advertising, and live entertainment.

Ms. Champlin leverages the firms’ global platform to help clients navigate overlapping multijurisdictional antitrust approvals from competition authorities around the world, involving the US Department of Justice (DOJ), the US Federal Trade Commission (FTC), the European Commission, the Canadian Competition Bureau, Mexico’s Comisión Federal de Competencia Económica, and China’s State Administration for Market Regulation.

She regularly counsels clients on competitor collaborations, information sharing, and sales and marketing practices, including price discrimination. Ms. Champlin also conducts economic analyses of mergers and other complex antitrust issues.

Ms. Champlin maintains an active pro bono practice and serves on Latham’s Pro Bono Committee. She has represented the Polaris Project, an anti-human trafficking organization; a tenant association in litigation involving housing code violations in Washington, D.C.; elder law clients; and children in individualized education program proceedings against DC Public Schools.

Ms. Champlin regularly writes and presents on topics related to antitrust law, including for law schools, academic journals, and the American Bar Association.

Ms. Champlin serves as a member of W@Competition, an organization for women competition professionals.

Ms. Champlin’s experience includes advising:

  • Agrium on its US$36 billion merger of equals with PotashCorp
  • Avago Technologies on its US$37 billion acquisition of Broadcom
  • Custom Sensors & Technologies on its US$1 billion sale of its sensing portfolio to Sensata Technologies
  • Energy Capital Partners on the US$370 sale of Transit Energy Group to ARKO Corp.
  • Energy Transfer LP on its US$7 billion acquisition of Enable Midstream Partners
  • Energy Transfer Partners on its US$18 billion combination with Regency Energy Partners
  • Ensco on its US$850 million acquisition of Atwood Oceanics
  • Entercom Communications on its US$105 million acquisition of Lincoln Financial Media
  • EP Energy on its US$1.5 billion sale to EnCap Energy
  • EssilorLuxottica on its US$6 billion acquisition of GrandVision
  • Live Nation Entertainment on extending a consent decree with the DOJ for the company’s merger with Ticketmaster
  • Nissan on acquiring a US$2.2 billion controlling stake in Mitsubishi Motors, winning 14 unconditional clearances globally
  • Novelis on its US$2.8 billion acquisition of Aleris, including through the first-ever US merger arbitration
  • NRG on its US$3.6 billion acquisition of Direct Energy
  • Rowan Companies on its US$2.4 billion merger with Ensco
  • Sasol on its Lake Charles Chemical Plant joint venture with LyondellBasell
  • Siemens on its US$7.6 billion acquisition of Dresser-Rand
  • US Sugar on acquiring Imperial Sugar, including through successful merger litigation against DOJ and unanimous Third Circuit affirmance
  • Veyance Technologies on its US$1.9 billion acquisition by Continental AG
  • Viasat on its US$7.3 billion combination with Inmarsat
  • Weatherford on selling its US hydraulic fracturing business to Schlumberger
  • Xerium Technologies on its acquisition by Andritz AG

Bar Qualification

  • District of Columbia
  • Virginia


  • JD, George Mason University School of Law, 2011
    magna cum laude
  • BA in Economics, Colgate University, 2008
    magna cum laude
Facade FlagsJustice Department Building Pennsylvania Avenue Washington DC Completed in 1935. Houses 1000s of lawyers working at Justice.
July 26, 2023 Recognition

Litigator of the Week Runners-Up and Shout Outs

Latham team recognized as appellate court affirms previous decisions against the US Department of Justice's challenge to U.S. Sugar's purchase of Imperial Sugar.