Jeannemarie O'Brien


Jeannemarie O'Brien

Jeannemarie O’Brien is a partner in the New York law firm of Wachtell, Lipton, Rosen & Katz, where she is active in the firm’s merger and acquisition practice, focusing on the executive compensation and employee benefits aspects of transactions, with a particular emphasis on transactions involving financial services institutions.  She has been involved in many major domestic and international merger, acquisition and buyout transactions, strategic defense assignments and proxy contests.  Ms. O’Brien also advises companies and their boards on governance issues and assists companies and senior executives on executive compensation matters in both the public and private sectors.

Transactions in which Ms. O’Brien has recently been involved include many major financial institution transactions, both bank and non-bank, and transactions in a variety of other industries, including:

  • Capital One in its pending $35.3 billion acquisition of Discover Financial Services
  • AbbVie in its $10.1 billion acquisition of ImmunoGen
  • Hess Corporation in its pending $60 billion all-stock acquisition by Chevron Corporation
  • BGC Group, Inc. in the investment by a consortium of 10 banks into FMX
  • RTX Corporation in its $1.3 billion sale of its Cybersecurity, Intelligence & Services business
  • The Goldman Sachs Group Inc. in its sale of its GreenSky platform and associated loan assets to Sixth Street and in partnership with others
  • The Cigna Group in its sale of its Medicare Advantage, Cigna Supplemental Benefits, Medicare Part D and CareAllies businesses to Health Care Service Corporation
  • PGA TOUR in an up to $3 billion investment by Strategic Sports Group in PGA TOUR Enterprises
  • Greenhill in its $550 million all-cash acquisition by Mizuho
  • American International Group in its $4.5 billion sale of its Validus Re business to RenaissanceRe Holdings Ltd
  • The PNC Financial Services Group in its $11.6 billion acquisition of BBVA USA Bancshares
  • Webster Financial Corporation in its $10.3 billion all-stock merger of equals with Sterling Bancorp
  • BMO Financial Group in its $16.3 billion acquisition of Bank of the West
  • United Technologies in its $147 billion merger of equals transaction of its Aerospace business with Raytheon, forming Raytheon Technologies Corporation, and its spinoffs of Otis Worldwide and Carrier Global

Ms. O’Brien frequently writes and speaks on executive compensation and corporate governance issues and is recognized as a leading executive compensation lawyer in the Chambers USA Guide to America’s Leading Lawyers for Business and The Legal 500.  In addition to memos and articles on recent developments in the executive compensation area, she is an author of the chapter on executive compensation in the Wachtell, Lipton, Rosen & Katz “Financial Institutions M&A,” an annual review of significant developments.

Ms. O’Brien received a B.A,. cum laude, from Mount Holyoke College and a J.D., cum laude, from Fordham Law School, where she was an associate editor of the Fordham Law Review.  She is a member of the New York State and American Bar Associations.

Ms. O’Brien serves as a member of the Board of Trustees of the non-profit organization Prep for Prep and a member of the Dean’s Planning Council of Fordham University School of Law.

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