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John J. Zak

Partner, Investment Management & Compliance, Securities Regulation & Corporate Compliance Practices Leader; Mergers and Acquisitions Practice Co-Leader

John concentrates his practice in U.S. securities regulation and compliance, mergers and acquisitions, and corporate law and governance. He is active in the firm's U.S.-Canada Practice and regularly counsels Canadians on U.S. securities, investment management, and corporate law matters. He has extensive experience in public and private securities offerings, venture capital and private equity transactions and executive compensation arrangements. He also counsels a variety of privately held companies.

John is a co-author of the Practical Law Company module on New York business corporation law.

John exclusively practices U.S. law and is admitted to practice in New York. 


  • Listed, Best Lawyers in America (Corporate Law) 2009 - 2021
  • Listed, Chambers USA: America’s Leading Lawyers for Business, 2019 - 2020
  • 2013 Best Lawyers Buffalo Corporate Law “Lawyer of the Year”


Presentations & Events

Professional Associations

  • Rex Energy Corporation board of directors (Nasdaq: REXX), Chair of Compensation Committee
  • New York State Bar Association Business Law Section Securities Law Subcommittee
  • American Bar Association Section on Corporation, Banking, and Business Law

Community & Pro Bono

  • Shea's O'Connell Preservation Guild Ltd. board of trustees (Shea's Performing Arts Center), Chair
  • Buffalo Philharmonic Orchestra Foundation, Inc., Chair